Fraser has two new patients inbound - E2V ARGUS 4 & Seek Reveal Pro FF - Page 1
Forum section: electronics / general

author: Fraser
author_rank: Super Contributor
timestamp: June 24, 2020, 01:37:13 am
content: I blame it all on the lockdown that the UK is in at the moment ! It made me do it, honestWhat am I talking about ? Well as regular readers of my posts will know, I have stopped my intensive searching of eBay for thermal imaging camera bargains since January 2018. My resolve weakened this week however and I bid on some suitably interesting and well priced "spares or repairs" cameras that caught my wandering thermal eye. I first saw the relatively rare sight on eBay of an E2V Argus 4 fire fighting camera that was being sold 'as-is'. It looked to be in pretty good condition and was shown working in the auction (always a good sign) The camera was not only an Argus 4, but the higher resolution model '320' that has a frame rate of 60fps. The model was stated as the higher specification HR320 but the camera straps show the standard spec '320' blue logos. We will have to wait until the camera arrives to establish its exact model and specification. Either way, both are QVGA and of very high qualityI already have two ARGUS 4 series cameras and own several of the very nice optional accessory modules that fit into the battery bay. E2V Argus offered battery modules that provide Wi-Fi/LRT IP streaming, Wired Ethernet IP streaming, Analogue composite Video, Digital Video Recorder and External Power for static installations. It is a very versatile fire fighting and surveillance cameraThe camera has its own picture storage and can store imaged for later viewing or download via USB to a PC. More about the camera once it arrives.The Seek Reveal Pro camera will be well known to many readers of this forum. I already own the standard <9fps and 15fps Fast Frame versions. The eBay auction was offering a faulty Reveal Pro Fast Frame so it was far more interesting to me than a standard Reveal model that the seller was also offering in another auction. For those unaware, the difference in image quality between a Standard Reveal and the Reveal PRO is significant and far more than just the pixel count. The reveal Pro contains a decent image processor IC and more features than the standard Reveal model. For this reason I was tempted to bid on it. The fault looks potentially nasty though. The auction image is pretty awful so little can be determined from it, but the seller stated that the display showed a thermal image with varying temperature measurement readout but with vertical lines present. It could be just a faulty LCD panel that I can source for around $30 from China, or it could be a fault in the microbolometer..... two ends of the fault spectrum in terms of repair ! Thankfully the Reveal cameras use a relatively common LCD panel. I am wondering whether the fault lies elsewhere however, such as the power supply buck and boost converters. The vertical lines appear equidistant from eachother, suggesting to me that an fixed frequency signal is involved. Hopefully it is not a failed microbolometer as that would render the unit a spares donor only, I do own a suitable spare Seek Thermal Pro microbolometer that could be fitted, but calibration would be an issue. We shall have to see what the symptoms suggest once I have the unit in my hands.Needless to say, both of these cameras fall into the 'bargain' price category for eBay sales, especially at the moment with increased interest in thermal cameras and so, higher prices. I was fortunate but must harden my resolve to not search for any more 'bargains'Watch this space for an update on the two units once they arrive, hopefully later this weekFraser

author: Collat3ral
author_rank: Contributor
timestamp: June 25, 2020, 09:13:30 am
content: I think I found the same bidder. Trying my luck on some items

author: railrun
author_rank: Regular Contributor
timestamp: June 25, 2020, 09:41:42 am
content: Fraser, are you the buyer? Never seen this camera before.https://www.ebay.com/itm/DYNAMIC-ATHERMALIZATION-FLIR-INFRARED-UNIT/402306300169?hash=item5dab52f909:g:Z6gAAOSwAwVe86fs#vi__app-cvip-panel

author: Fraser
author_rank: Super Contributor
timestamp: June 25, 2020, 11:50:36 am
content: No, not me 🙂I do not recognise that camera or the manufacturer.It will be a specialist product and the challenge with such is controlling them without the command set or driver software. As such I tend to avoid them unless a real bargain.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: June 25, 2020, 11:58:44 am
content: Collat3al,Good luck.The one with the dead battery looks promising. Be careful spending much on any that are not displaying a thermal scene as a dead microbolometer module renders them good for parts only. I bought the Reveal Pro because the seller stated that it’s measurement Function was responding to thermal stimulus so I am hoping the microbolometer module is OK. For information, the Reveal does not use a Mosaic core, or even the standard complete Seek Thermal Core module. It interfaces the microbolometer PCB direct to the video processor on the main board without the usual J3 core processor PCB that outputs USB. Buying these is very much a calculated risk as faults in the firmware memory or the Image Processing chipset will render them likely beyond repair.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: June 25, 2020, 12:10:31 pm
content: The Argus 4 arrived today. The Seek Reveal Pro has yet to be dispatchedThe Argus 4 is an Ex Fire Brigade training unit that has an intermittent fault with the FFC flag. At first power on the camera sometimes suffers a stuck FFC shutter in the closed position. Further investigation will be required but it is hopefully a mechanical issue that can be easily rectified. Once ‘unstuck’ the FFC shutter works normally and an excellent image is produced. More about this camera when I get a chance to spend some time on it. It’s good condition and lack of the usual smoke smell is likely because it is a training unit so never saw a true fire in its life.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: June 25, 2020, 12:49:20 pm
content: For information. I was going to bid on the Seek Reveal with a dead battery or charge circuit but if there is interest from others on the forum, I will step back on this camera. I believe that camera to be eminently repairable, but the other three to be somewhat of an unknown quantity ! I would not recommend buying a faulty Seek camera unless you can afford to write off the money spent on it. They are highly integrated units so faults can be a challenge to track down and repair. Caveat Emptor and all that. Please do not blame me if you buy a dud from this seller as they are clearly customer returns with unknown history. Like mobile phones they can suffer abuse, such as being dropped or submerged in waterI bought a camera that looked to be mainly functional so it was a calculated risk and worst case scenario, spares for my other two units.Fraser

author: Bill W
author_rank: Super Contributor
timestamp: June 25, 2020, 01:10:59 pm
content: Quote from: Fraser on June 25, 2020, 12:10:31 pmToss a coin between:Part cold weld of the flag to the end stop where it has worn through the anidising. Gentle polishing will fix, maybe some mylar tape.Clearances issue, later cameras had a tiny ptfe washer added.Either way a total pain to get to on these cameras - so a very comprehensive teardown is likely to result.Bill

author: Fraser
author_rank: Super Contributor
timestamp: June 25, 2020, 02:16:08 pm
content: Dear Bill,Thanks for this.So I have a voyage of exploration to undertake with the 320. The cold weld issue is a new one on me. I thought there might be a rubber end stop pad that had become slightly sticky.Wish me luck with the journey into the deepest, darkest parts of the Argus 4 cameraI used to dismantle and service Gov’t grade Combination locks and Siemens T100 electro mechanical teleprinters, so mechanical disassembly of equipment holds no fear for meFraser

author: Fraser
author_rank: Super Contributor
timestamp: June 25, 2020, 02:25:21 pm
content: Bill,Out of interest, why is the Argus 4 320 so much more complicated on the disassembly front than the 160 model ? Were other changes done beyond a different (physically larger) microbolometer that required a redesign of the front section component parts ?Fraser

author: Bill W
author_rank: Super Contributor
timestamp: June 25, 2020, 03:40:33 pm
content: Quote from: Fraser on June 25, 2020, 02:25:21 pmThe case was designed for the 160x120 35µm sensor, and so a 6.3mm f/1 lens. No allowance was permitted (we did ask) for any larger sensor or lens. "Firemen will never pay for a 320 sensor".So on the original Argus4 the sensor PCB comes out as a complete assembly with minimal clearances.So when we did (inevitably) put in a 320 sensor with an 8.6mm f/1 lens, and that larger diameter still needs to see out of the case, which is quite thick there.So the lens ends up partly through the case wall and the sensor PCB assembly is captive until you undo the lens.Naturally the lens needs a tool and has threadlock and a grub screw just to make it harder.

author: Fraser
author_rank: Super Contributor
timestamp: June 25, 2020, 03:49:16 pm
content: Thanks Bill,I now see the issueThankfully you recommended a suitable screwdriver for the lens lock a while back and I bought one. I also have a range of adjustable lens spanner’s with various tips so hopefully have the covered as well. Acetone will deal with the thread lock varnish, as it did with another lens that you kindly gave to meThank you for the picture. That really helpsDon’t you just love it when the casing design team refuses to consider the expert input from the electronics payload teamFraser

author: Bill W
author_rank: Super Contributor
timestamp: June 25, 2020, 04:45:36 pm
content: Quote from: Fraser on June 25, 2020, 03:49:16 pmTo be fair to them, the mechanical folks were OK either way. The problem was the product specification coming from sales. When challenged with 'Can you guarantee that we will never ever ever need to fit a 320 sensor in this box ?' they replied 'Yes'.This was despite still selling Argus 3 with 320 sensors in them at the time. It was more that they were getting hit by Bullard T3's - smaller cheaper - so wanted something smaller and cheaper.At least they were talked out of putting the batteries in the handle. I was probably never forgiven for saying "OK, so how would you use the camera without the handle if that is where the batteries are ?'Bill

author: Fraser
author_rank: Super Contributor
timestamp: June 25, 2020, 05:02:45 pm
content: Bill,One of the features of the Argus 4 Design that I love is the “option port” on the top of the casing that is home to the battery pack or several other option modules that incorporate a battery for the camera as well. It is a really excellent ideaNow that I have Sourced most of the optional modules, my Argus 4 cameras are very versatile indeedAs to placing the battery in the handle....... nope ! As you say, the handle should be optional. A handle has its place but should not be a fixture unless it can fold up out of the way on a knuckle joint.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: June 26, 2020, 01:27:41 am
content: Just in case it helps anyone, I will provide my thoughts on the three faulty Reveal units that are on eBay from the same seller as my unit.To be clear, these cameras are in no way connected with me and I do not know the seller. They are customer Raw returns that the seller has plugged in and switched on. We are reliant upon the sellers description and pictures provided but I can assess some aspects of the units from that information. I will not be held responsible for any errors I make however !Seek Reveal XR30 - CamouflagePhysical condition? : Looks GoodCompletes Boot ? : YesDisplays expected OSD and thermal scene ? : YesFault : The camera apparently will not run from its internal battery but will run from its USB socket. This suggests to me a failed battery (locked out?) or a failure in the charging/power management IC.Repairable by competent person ? : Yes, eminently repairable as the battery sub system is not complex.Seek Reveal XR30 BlackPhysical condition? : Looks GoodCompletes Boot ? : Yes with a caveat - no thermal scene is produced on the display.Displays expected OSD and thermal scene ? : No.Fault : The camera apparently boots to the point of presenting the OSD bars but fails to display a thermal scene or temperature measurement. The lack of a temperature measurement may just be down to the measurement mode not being selected. The blank display could be a stuck/damaged FFC flag mechanism. This is quite fragile but I would not expect a 'perfect' blank screen in this particular FFC flag actuator design. The unit may well have booted to the point of displaying the OSD but halted due to an issue in the final stages of the boot sequence.Repairable ? : We lack the information to determine the actual state of the camera after/during boot. It is an unknown and could be a basket case if the problem is in the VLSI side of the unit. Firmware corruption is a possibility but I cannot be sure of that. A fault on the Microbolometer cannot be excluded. This unit would be a risky purchase.Seek Reveal Pro Black (carbon fibre look)Physical condition? : Looks GoodCompletes Boot ? : No - no thermal scene or OSD is produced on the display.Displays expected OSD and thermal scene ? : No.Fault : The camera apparently boots to the point of presenting the SEEK logo and Measurement overlay but fails to display the OSD bars or a thermal scene. The blank display could be a stuck/damaged FFC flag mechanism. This is quite fragile but I would not expect a 'perfect' blank screen in this particular FFC flag actuator design. Then there is the displayed temperature measurement.... it is reading 32F and that is 0C ! With a stuck FFC flag I would not expect to see a measurement of 32F(0C) That particular aspect of the displayed symptoms is worrying.Repairable ? : We lack the information to determine the actual state of the camera after/during boot. From what can be seen though, the camera had not correctly completed the full boot sequence, or if it has, it has crashed soon after. The displayed temperature measurement is pure fiction and indicative of something very strange going on on the measurement side of the system. There is an ambient temperature monitoring sensor in the camera but failure of that would not produce a 0C measurement reading. To me that reading suggests a default value used in the cameras measurement system against which the readings from the microbolometer are offset. What is causing this I cannot say, but a failure on the microbolometer PCB should be considered a possibility.OK there are my thoughts on these units. I hope they help anyone interested in them. I already have my very own Seek Reveal project and I hope to repair it when it arrives. If you buy one of these three units, I wish you well with the repair but please do not ask me to help. I just do not have the time and remote repair is a total nightmare ! Please do consider how much to spend on any faulty SEEK product as working used units are selling at reasonable prices. A Reveal Pro in its box sold for just over 200GBP yesterday. These units are not that easy to work on and would not be what I would call a beginners project. Only spend money on these if you are willing to accept it may be beyond repair. There is a good reason why customer returns like these basically get dumped. They are not a commercial repair proposition.Now if these were FLIR PM series industrial cameras..... I would be all over them like a rash as I love working on those little beautiesFraser

author: Fraser
author_rank: Super Contributor
timestamp: June 26, 2020, 12:42:04 pm
content: The seller has added another Seek Reveal listing for a dead unit that does not start or operate the LED. The fault could be varied as no further information is provided except that the buttons feel “solid”. That does sound weird.The seller has opened the unit to see if it was a dummy (display model). It apparently contains a main board and battery.The only concern I have is that the seller even bothered to open the unit. Have the others also been opened I wonder. I personally like to work on virgin returns that have not been messed with in any way. Most returns resellers will not wield a screwdriver as they just want to shift stock. It makes me a little nervous that this seller is not afraid to open these unitsWe can only hope no parts swapping has been going on. Caveat Emptor and all that.I am thinking the seller might be working their way through a bulk lot of Seek Reveal units from a company like Amazon. They appear to test a few, list them and then test a few more and so on. For anyone thinking of buying a Seek Reveal repair project it may pay to wait until something is listed that does not look like a total basket case or high risk. I am certainly pleased that I bought a Reveal Pro that looks function albeit with a display issue.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: June 26, 2020, 12:56:00 pm
content: Anyone thinking of taking on a Seek Reveal repair project would be wise to look at Mikes teardown of a Reveal Pro and someone else’s teardown of a Reveal. I will add the links in a minute.The Reveal and Reveal Pro use different main boards and Microbolometer PCB’s. The microbolometer calibration data is held on the main board chipset. Unlike designs with multiple PCB’s, the Reveal design does not lend itself to the old “make one good unit out of two dead ones” approach. You have to swap chips if you want to go down that path and then you have to consider any data held in the chips that is camera specific. I advise caution if anyone thinks the Reveal or any other Seek Thermal camera will be a simple fix if it has more than a simple power management or battery fault. A broken USB connector is always a possibility on a unit that will not charge. This is especially so on the Standard Reveal as it does not have USB socket strengthening.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: June 26, 2020, 12:58:14 pm
content: Seek Reveal Pro teardown by Mike....https://youtu.be/mgaBAm_sRnkFraser

author: Fraser
author_rank: Super Contributor
timestamp: June 26, 2020, 01:00:37 pm
content: Seek Reveal Teardown by Alex Udanis.......https://www.allaboutcircuits.com/news/teardown-tuesday-thermal-camera/Fraser

author: Fraser
author_rank: Super Contributor
timestamp: June 26, 2020, 01:06:41 pm
content: As can be seen in the above teardowns, the Reveal is a highly integrated electronics package so there is not much that can actually be ‘repaired’. If a fault is in the main processor, the camera is likely toast. If it is a BGA solder ball fault, rework may be an option but it is not a task for the faint hearted !Firmware corruption can be a possibility, especially if a camera loses power during the update process. It is a sure way to brick a camera and is potentially unrecoverable by most users. Firmware updates that have gone wrong or attempts to hack firmware can result in a very dead camera that may not be worth the hours needed to unscramble the mess and repair it, even if possible. Flash memory corruption through no fault of the user is also a possibility and the seek Reveal is known to have an issue with Flash memory self corruption.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: June 26, 2020, 01:18:33 pm
content: The Seek Reveal series are a good example of why I effectively ceased to be a component level repair technician in my working life. The level of integration can make a piece of equipment challenging to diagnose without diagnostic software and ‘bed of nails’ test jigs. When a PCB contains just a very few lumps of clever silicon running code that is not public and the power supplies and other supporting hardware is present and correct..... you are faced with board replacement as the fastest means of repair and it is sometimes the most economic path to take. This is why Radio Officers, like me, on Ships became obsolete. ‘Techs’ were then employed who only knew how to follow board change or even whole equipment change routines. The OEM repaired the kit back at the factory.Modern electronics is becoming more and more integrated and is often more of a hardware-software symbiotic hybrid that can be very challenging to work on without inside knowledge and diagnostic utilities. The thermal cameras I tend to repair are from a slightly earlier period where multiple PCB’s were used and, whilst they remain complex, the PCB’s contain separate processors, RAM, ROM, I/O glue logic and FPGA’s. With those units I have a chance of locating the fault and correcting it. In the case of the FLIR PM series you are basically working on a MC68K series based computer much like the Amiga 520 !

author: Fraser
author_rank: Super Contributor
timestamp: June 26, 2020, 02:08:11 pm
content: The teardown by Alex revealed the identity of the two security screws that secure the front metal section to the cameras casing. They are Bryce Pentagon centre pin screws that require a hollow pentagon driver bit. They are not pentalobe.https://www.brycefastener.com/penta-plus-vandal-proof-screws.htmlFraser

author: JimM
author_rank: Regular Contributor
timestamp: June 26, 2020, 07:35:53 pm
content: QuoteThat's really surprising to me. I would have thought Seek would have used the same main board for the Reveal and Reveal Pro for commonality of parts, firmware/software, etc. You could easily account for the difference in resolution between the Reveal and Reveal Pro in firmware code. Instead the board has different processor and even a different USB connector mounting.You certainly can't liberate a Reveal to a Reveal Pro like you can a FLIR E4 to a FLIR E8 through firmware/software changes. (On second thought, maybe that's why Seek took the approach they did!)

author: Fraser
author_rank: Super Contributor
timestamp: June 26, 2020, 11:20:53 pm
content: A tiny update on the a Argus 4 320 camera.I accessed the cameras “About” page in its setup menu and it only has 111 hours on itAccessing the stored images revealed that it was used during fire fighter training from 2014 until late 2016. The cameras sticking FFC shutter problem initially occurred in early 2016. It was used in training for a little longer with the intermittent problem present, but looks to have been removed from service in late 2016. Why this camera was not repaired, I do not know. It was certainly not a cheap purchase and repair would normally be sought by the Brigade.I just spent a few minutes listening to the camera as it booted with my ear pressed to the case. What you should hear after starting the camera is the FFC shutter being activated at very short intervals as the camera takes some FFC readings during the microbolometer warm up period. The period between FFC events then increases greatly once the microbolometer temperature has stabilised.With this model of camera there is normally a very clear ‘clunk’ when the FFC shutter operates. On the faulty camera I carried out a series of 10 bench mounted starts with a run time of a few minutes each to see what happened. The blank screen remained throughout. When listening to the camera I could hear the faint sound of the FFC solenoid being energised but no associated ‘clunk’. This is because the FFC shutter was already in the activated position (closed). Having proven my suspicion about the stuck FFC shutter, I gave the cameras front rubber buffer a light tap and was rewarded with The thermal image appearing on the screen and the next FFC event occurred normally. The camera behaved itself perfectly after this little test exercise.So, as Bill said, I will be delving deep into the microbolometer block assembly to carefully inspect clean and ‘Tweak’ the FFC flag mechanism to remove its penchant for sticking in the enclosed position if left inoperative for very long.Bill can you provide any more detail on where the thin PTFE washer was placed to create a better clearance please ?I like faults like this. With many mechanical issues you see or hear what is happening, or not happening and your ears combined with an experienced diagnostic brain can image the problem before you even see it. It is like listening to a car engine, you get to know what it should sound like and any deviation in that sound profile is often detected by the experienced ear of the owner or mechanic.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: June 27, 2020, 01:06:07 pm
content: The faulty Seek Reveal Pro arrived a few minutes agoThe unit arrived in its original “Export Controlled” box along with its lanyard and USB cable. Battery was at 80% charge.I switched the camera on and was pleased to see a perfect boot screen, followed by a noisy thermal scene. The LCD panel is perfect, no fault there. One golden rule before reaching for the screwdrivers is to full assess the patient and note any symptoms that might help localise the fault location to a sub system within the camera. Once this is done, always carry out a full system restore if such is offered. This can flush out ‘bad’ data from the configuration that could be causing issues. A full cold boot is also recommended but that may require removal of the battery in some equipment.OK, to my Reveal Pro patient...... I am very pleased with what I am seeing. The camera is correctly imaging the thermal scene and trying to measure the spot temperature. The problem is that there are vertical lines all over the scene so the measurement is jumping all over the place. I checked stored images and they are the same except with static vertical lines of course. All menu options operate as expected with no other fault symptoms. A system restore did not change the symptoms.From this simple observation I am able to make some early deductions......1. Battery appears OK2, firmware is OK and not corrupted3. System is running and not crashing so no fault is being detected or encountered4. System is oblivious to the vertical lines present being a fault and is treating them as thermal data from microbolomter.5. The vertical lines are dynamic and fast moving in the lateral direction when viewed. Some might describe them as random rather than predictable or static.The Seek Reveal operates with the thermal core rotated 90 degrees to provide a portrait image format. The human brain interprets what it sees and tries to rationalise it using memories. The vertical noise looks like nothing particularly familiar but when you rotate the camera 90 degree to create a landscape image the lines immediately take on a more familiar pattern(for me anyway)With the camera display in landscape orientation the noise lines are clearly just that..... noise. They are what I have come to expect in an analogue system that has noise on a power supply rail feeding a sub system that directly deals with image creation from an analogue input. The power rail noise becomes superimposed on the analogue signal and becomes part of that signal, just like a mixer..... though an unwelcome addition is added to the wanted signal.So from my very early days diagnosis I suspect that there is a Buck or Boost converter that is producing a noisy output and that power rail is used to power the microbolometer PCB, or an analogue sub system that follows, before the high speed ADC translates the analogue image into the digital domain used by the image processor. It could even be noise on the ADC supply rail.Well that will do for now. I am very pleased with my purchase and hope to return it to full health when I get some spare time. Such is in short supply at the moment. I have not had to open the casing yet ..... I like this kind of closed case diagnosticsAs a side note...... From witness marks on the screw heads, I have a suspicion that someone went in search of easy to fix ‘loose wires or connectors’. Not an unreasonable action but not what I like to see as it can indicate ‘fiddle fingers’ have been inside a unit. If anyone is thinking of buying one of these faulty units in the hope of a loose connector type fault, I suspect you will be disappointed if the seller has been inside looking for the same.We do not know the history of these units but the sellers company name is known to me and they are basically a professional WEEE waste processor who take electronic waste and recycle it. They clearly also do a side line in selling some kit on eBay ! There is likely a tidy profit to be had as such waste disposal companies normally charge the originating company for disposal of WEEE waste based on weight.I suspect these Seek Cameras came from a large retailer as Seek Thermal would likely have wanted them crushed if a U.K. service centre was the source.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: June 27, 2020, 01:29:06 pm
content: So when I return to the Seek Reveal Pro repair what will my next moves be ? Will I dive in with an oscilloscope hunting for noise coming out of Boost / Buck converters Or something else ?Well it will be something else. I obtain valuable experience and knowledge when working on equipment that I repair. I make the most of the experience if it is a job for myself. I will reverse engineer the Seek Reveal Pro design topology and gather data sheets for all major components. I will then create a basic reverse engineered system diagram showing key components and points of interest. This document will help me when working on other cameras of the same model, if I should ever need to work on one.Diving in with an oscilloscope would possibly track down the supply rail noise issue but this is offset by the lack of knowledge extracted from the repair and can also be inefficient if some form of reverse engineering node plot has not been undertaken to identify useful test points and connectivity.That is why I will not be diving into the Seek Reveal Pro today. I will take my time working on it as the knowledge gained is often worth more to me than the price paid for the equipment. Remember, I already own a Reveal Pro and a Reveal Pro FF so this patient is “just for fun and learning”Fraser

author: Fraser
author_rank: Super Contributor
timestamp: June 27, 2020, 01:37:03 pm
content: Before anyone asks.....With regret I do not share reverse engineered schematics for any thermal imaging cameras. It is legally too complicated on many levels. I detail my approach to this repair only as guidance to others who wish to follow the same path.And remember .... these highly integrated ‘system on a chip’ based units are as much firmware as they are hardware. Schematics can only help to a certain point when firmware issues are involved.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: June 27, 2020, 07:03:34 pm
content: Some pictures of the Seek Reveal Pro fault. I will also download better images saved on the camera.

author: Fraser
author_rank: Super Contributor
timestamp: June 27, 2020, 07:09:26 pm
content: The pictures as saved on the camera.The temperature measurement is hilariously wrong but this appears to be related to the noise signal presence.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: June 27, 2020, 07:17:51 pm
content: Some saved pictures in the landscape orientation showing the dynamic nature of the noise barsThe camera is looking at the ceiling as a low Delta T target.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: June 27, 2020, 07:33:34 pm
content: Regarding the pentagonal security screws that used to be fitted to the seek Reveal series. I am pleased to advise that all three of my Seek Reveal units are fitted with standard T9, 6 point, Torx socket head screwsSeek obviously changed their mind about the use of such security screws.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: June 28, 2020, 04:08:28 pm
content: I just checked the Seek Thermal Datasheet for the J3 sensor board that hosts the microbolometer. It’s only I/O is SPi and 8 bit parallel data. All analogue processing takes place on this J3 PCB so its power supply will be carefully scrutinised. The 0V rails will also be checked for performance.Fraser

author: Bill W
author_rank: Super Contributor
timestamp: June 28, 2020, 09:45:22 pm
content: Step one: shake the camera and see how many capacitors fall out.Bill

author: Fraser
author_rank: Super Contributor
timestamp: June 28, 2020, 10:31:10 pm
content: I know exactly what you meanSadly no rattles in this caseI might find an unpopulated capacitor pad thoughIt will be interesting to see what is going on with the unit. I still think it is the best of the bunch listed as some of those others are a real gamble.Regarding components floating around in a faulty unit..... I had some units (not cameras) that all failed to start and all rattled. Upon investigation the rattle was an SMD inductor in every unit. A production defect caused a power rail short that overheated the inductor that was in series with that power rail and desoldered itself. Power was then cut and the unit became one of a whole bunch of dead customer returns. It proved the units had never been power tested at the factory, despite the ‘QC’ labels. An easy repair though.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: June 29, 2020, 02:10:38 pm
content: Well the auctions for the faulty Seek Reveal cameras have completed. It would appear that I got myself quite a bargain if the end prices of those auctions are anything to go by ! Wow!Did anyone here succeed in winning one ?Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 09, 2020, 04:59:04 pm
content: Just checked the Seek Reveal Sellers feedback from buyers. Not a single feedback for the Seek Reveal cameras (Except mine) since they sold 10 days ago. That strikes me as a little unusual unless all were bought by one person and they have yet to receive them/leave feedback. Sadly the seller has no more listings for Seek Thermal products.I must get around to delving inside my Seek Thermal Pro. I am itching to see what the problem is.Fraser

author: ratmole
author_rank: Contributor
timestamp: July 16, 2020, 11:16:41 am
content: Quote from: Fraser on July 09, 2020, 04:59:04 pmjust open the device and re-seat the flex cable from the camera to the main pcb!you can guess on how do i know it!thanks!

author: Fraser
author_rank: Super Contributor
timestamp: July 16, 2020, 12:22:56 pm
content: Ratmole,Thanks for the suggestion. I too have found poorly seated or poor quality ribbon connections to be a cause of issues in portable equipment. It always pays to disconnect, inspect, clean and reconnect all ribbon cables before diving in with the full diagnostic too setIn rugged equipment it is common to either find very high quality ribbon connection systems or some form of strain relief/securing solution in place. Ribbon cables of the clamp connector type are well known for moving due to impacts or just ribbon creep due to tension. I shall do as you suggest and look at that ribbon todayI have time for that, but sadly little more at the moment.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 16, 2020, 12:38:34 pm
content: Ratmole,Would I be right in thinking that you bought at least three of the Reveal units from the same seller as me ? I see that three of them are for sale on eBay from a seller (you?) in Greece so it appears they were repairable. It would be great to hear about your experiences repairing them if you are willing to share. Some looked simpler than others. The totally dead units were the big unknown as symptoms were understandably limited !The one that the seller opened to check it was complete sounded weird as the comment that the buttons were very hard sounded like they were significantly different to the other units that the seller was testing before sale.I saw that the blue Reveal with missing USB cover came up again for sale again. I wonder what happened there ? I did bid a small amount on it, but once it went over my financial risk threshold I lost interest.Did you buy the other PRO unit ? It looked like it could be a viable repair, possibly a ribbon cable issue ? but the temperature reading of 32F was a bit weird.I am pleased with the unit I bought and I hope you were pleased with your purchases as well. If you get a chance to buy a Reveal Pro, it is an impressive little unit and significantly better than the standard Reveal model in all respects. I might have bought the other Pro unit offered by the seller had its price not gone above my ‘bail out’ threshold.Best WishesFraser

author: Fraser
author_rank: Super Contributor
timestamp: July 16, 2020, 12:58:55 pm
content: Ratmole,My apologies, I forgot to welcome you to the forumI like your Forum name as wellWelcome and if you are new to the forum, I hope you find its contents of interestFraser

author: Fraser
author_rank: Super Contributor
timestamp: July 16, 2020, 01:13:37 pm
content: Someone got themselves a bargain today. An NEC AVIO 7700 in IMPAC branding for less than £400 ! Total bargain considering the quality of the imaging core and lenses used in these cameras. Only down side was that it is the European <9fps version rather than the normal US spec 60fps specification.https://www.ebay.co.uk/itm/impac-ivn-770-p-Thermal-Imaging-Camera-/164283222212?ssPageName=STRK%3AMEBIDX%3AIT&nma=true&si=t%252Fwx9yOgtQm9wpYWMFnsKCq%252FXCU%253D&orig_cvip=true&nordt=true&rt=nc&_trksid=p2047675.l2557And yes, I did bid on it, so if the buyer is reading this, sorry for raising the end price, but you still got a bargainI know quite a lot about NEC AVIO thermal cameras and even have the full service manual for one particular modelI have a very nice Germanium supplementary lens for the 7700/7800 series camera in my collection. It awaits a mounting adapter to fit my other cameras. A Top quality lensFraser

author: ratmole
author_rank: Contributor
timestamp: July 16, 2020, 01:20:43 pm
content: Quote from: Fraser on July 16, 2020, 12:38:34 pmi was going for it (the first one) but unfortunately i was outbid by you!no worries!

author: Fraser
author_rank: Super Contributor
timestamp: July 16, 2020, 01:29:34 pm
content: I rarely bid on ‘common’ thermal cameras these days. I go for the exotic modelsIt was a borderline decision for me to bid on the 7700 as I have never liked that particular series case design. It seemed ‘cheep’ compared to my other TH and TS series NEC AVIO thermal cameras. The imaging core is very nice thoughAs a side note, I have a licence for the excellent Thermography Studio software that NEC AVIO rebranded as their own under licence from Goratec and later, WhiteBlue Software. The software was sold under various brands by camera manufacturers as it had multi brand support. Sadly the software has kind of fallen into a Zombie development state as WhiteBlue stopped development and was looking to be bought out. My licence still works with all the various branded versions of ten Software thoughhttps://www.overloadsrl.it/easyUp/files/GTS08.pdfFraser

author: Fraser
author_rank: Super Contributor
timestamp: July 16, 2020, 02:02:41 pm
content: Ratmole,If you have an interest in thermal imaging cameras, You may like to look down my camera collection listhttps://www.eevblog.com/forum/thermal-imaging/frasers-thermal-camera-collection-the-definitive-list-regularly-updated/msg3025468/#msg3025468Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 16, 2020, 03:35:18 pm
content: Had a quick look at the Seek Reveal Pro. It was very easy to disassemble and took only a couple of minutesThe possible ribbon cable poor contact was checked and reseating the two ribbon connectors did not resolve the issue. The unit is now disassembled and will undergo further inspection and investigation as time permits.I will provide decent images of the PCB for others to use as trying to grab frames out of Mikes Reveal Pro teardown video can be challenging and not as detailed as a still image.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 16, 2020, 04:43:47 pm
content: Some quick snaps of the main and microbolometer PCB's follow. Please excuse the lack of scene lighting and less than great detail. Better will follow when I start the repair work.Fraser

author: ratmole
author_rank: Contributor
timestamp: July 23, 2020, 08:47:41 am
content: Fraser, can you please upload some high resolution images of the seek reveal pro pcb?thanks

author: Fraser
author_rank: Super Contributor
timestamp: July 23, 2020, 11:06:49 am
content: I will produce some better images of the Reveal Pro PCB. Is there any particular area of the PCB that is of special interest to you as I can add those areas as well. The forum file size limit impacts how high the resolution can be but I can always post images within those limits and upload full resolution images to a drop box.Fraser

author: ratmole
author_rank: Contributor
timestamp: July 23, 2020, 11:20:08 am
content: not interested on a particular areajust want to see some high res images of the pro pcbplease share the dropbox link if and when ready. thanks

author: Fraser
author_rank: Super Contributor
timestamp: July 23, 2020, 11:43:51 am
content: No worries. I will see what I can sort out today. I will upload to both the forum, within file size constraints, and to a drop box at full resolution.The Reveal Pro appears to be completely different to the a Reveal design. I hoped another Reveal series model would appear out of the Seek Thermal R&D department but alas the Shield and Fire models are just minor reworking of the standard Reveal Pro. Mostly firmware changes for specific tasking plus a different lens on the Shield model.No Radiometric TIFF image analysis software, no wireless connectivity, no tripod adapter, no video streaming, no manual focus lens. Opportunities missed ?Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 25, 2020, 04:19:59 pm
content: As requested, I have produced some higher resolution images of the PCB's with better lightingThe full 12MP camera image files are available from Filedropper (60MB total Zip File size)http://www.filedropper.com/hrpicsI will upload smaller 2MB images to this thread below.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 25, 2020, 04:21:28 pm
content: 1

author: Fraser
author_rank: Super Contributor
timestamp: July 25, 2020, 04:22:00 pm
content: 2

author: Fraser
author_rank: Super Contributor
timestamp: July 25, 2020, 04:23:13 pm
content: 3

author: Fraser
author_rank: Super Contributor
timestamp: July 25, 2020, 04:23:44 pm
content: 4

author: Fraser
author_rank: Super Contributor
timestamp: July 25, 2020, 04:24:29 pm
content: 5

author: Fraser
author_rank: Super Contributor
timestamp: July 25, 2020, 09:21:43 pm
content: I carried out some reverse engineering of the DC-DC converters and Microbolometer power supply today.The main component involved with the production of the various power rails is the Texas Instruments TPS65217C PMIC. It is an all in one power management chip that takes external power supply, USB and Battery inputs and automatically connects the best, or available option to the System power output. The IC also provides the smart charger circuit for a Lithium CellAs if this were not enough, the TPS65217C provides multiple DC-DC converters and LDO's to provide for a microprocessor system and a string of LED's !Outputs from the PMIC:SYS = 5V nominal. Selected power input passed to this pin to power the system. Normally the DC-DC converters and LDO's are connected to this pin.DCDC1 = 1.5VDCDC2 = 1.1VDCDC3 = 1.1VLDO1 = 1.8VLDO2 = 3.3VLDO3 = 1.8VLDO 4 = 3.3VSo which DCDC conveter or LDO powers the microbolometer ?The answer is... none of them !The SYS output from the PMIC provides a nominal 5V for use by the various DCDC converters and LDO's but it can also provide the main power rail for other IC's and their respective power supplies. This is what happens in the Reveal Pro. The SYS output rail is directly connected to the Microbolometer PCB connector and has no further filtering before doing so. It is therefore best considered a RAW power rail in need of some 'treatment' before being applied to the voltage and noise sensitive Microbolometer circuitry. At this point it was clear to me that the Microbolometer PCB must host a low noise LDO voltage regulator of some sort. I knew exactly where to poke around !Ever since looking at the Microbolometer PCB I have wondered about the function of the small 4 pin IC on the PCB edge, and its identity. It was now number one suspect that it was an LDO. Its positioning made sense as well as you do not want an LDO sat too close to a very temperature sensitive microbolometer die. Some quick continuity probing showed the component to indeed be some form of regulator. It received the power rail from the ribbon connector and supplies many of the components on the microbolometer PCB. The four pins are Vin, Vout, 0v and 'unknown'. I suspect the unknown pin is an enable input but this has yet to be confirmed. This LDO is nor marked with a number but there does appear to be a symbol on it. I thought it likely a Linear Technology device but I will need to investigate further.So where does this lead us ? Well I find it unlikely that the PMIC three way MOSFET switching is creating a noisy output at the SYS pin unless something has gone very wrong with the control circuit. If such were the case I would expect the camera not to boot correctly as SYS powers all other circuits associated with the processor. I will check it thoughThe little LDO regulator on the microbolometer PCB is currently the chief suspect in the investigation. Either it is in some form of failure or a support component that maintains its stability has failed. It has input and output capacitors that I will need to check. If the LDO is malfunctioning due to excess loading, I will need to investigate further down the line. I believe in keeping things simple though, so for the moment I will look at the small LDO circuit and see if it is producing excess noise due to self oscillation. I will also try to identify the component. Testing will reveal its output voltage and I can always fit another, compatible, part if such is required. We could just be dealing with a failed MLC.I attach a picture of the chief suspect in the investigation..... guilty until proven otherwiseThe reverse engineering was carried out visually and with continuity checks. No power was applied as that comes only after I know what I am 'poking'!Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 25, 2020, 09:36:03 pm
content: TPS65217 PMIC functional diagrams

author: Fraser
author_rank: Super Contributor
timestamp: July 25, 2020, 10:59:20 pm
content: The NCP140 LDO Regulator looks similar to that used on the Microbolometer PCB. The size of 1mm x 1mm matches. As I suspected, the fourth pin is very likely an “Enable” pin. It will be interesting to see what voltage appears at the output of the LDO. The NCP140 operates with, or without input and output capacitors so may be better than the LDO fitted in the Reveal Pro.https://docs.rs-online.com/de84/0900766b81628526.pdfRichtek make a similar device as well. It looks like I will have my choice of replacement parts if such is neededhttp://www.farnell.com/datasheets/2183318.pdf?_ga=2.73893776.30223683.1595718040-787969494.1589067057&_gac=1.23385160.1594899574.Cj0KCQjw9b_4BRCMARIsADMUIyr7bImqY48wb16DFj_Uoi3g3YNTRusSSK02WuPkx3PR13hb4sf-iNQaAsezEALw_wcBFraser

author: Fraser
author_rank: Super Contributor
timestamp: July 25, 2020, 11:26:35 pm
content: I could not resist checking the voltage at the LDO.Input voltage is a solid 3.8VOutput voltage is 2.8V but my trusty Fluke 87 III Bar graph display appears to show noise on the rail. A look with a scope will obviously be the next step but at least I now have an idea what voltage the LDO produces. Whether that voltage is correct and noise free we will have to investigate tomorrowFraser

author: Fraser
author_rank: Super Contributor
timestamp: July 25, 2020, 11:37:55 pm
content: As the PMIC is a TI part, I thought it possible that the LDO would be a TI part as well.This part looks like a possibility. The TI TPS7A02 series 1mm x 1mm LDO. It is available in 2.8V output and normally has input and output capacitors. This is just a first look with Google so I am not done yet but it is a start.https://www.ti.com/lit/ds/symlink/tps7a02.pdfFraser

author: Fraser
author_rank: Super Contributor
timestamp: July 25, 2020, 11:50:22 pm
content: I think I will be fitting high quality MuRata 0402 size 1uF, low ESR, MLC’s at the input and output of the LDO tomorrowFraser

author: Fraser
author_rank: Super Contributor
timestamp: July 26, 2020, 11:13:14 am
content: I woke up to a message from a friend in the USA today. He was sharing his knowledge of the Seek Pro dongle and its 2.8V Regulator that powers the microbolometer. In his testing, if you mess around with the value of the 2.8V regulator bypass capacitors it can create a rolling noise presence on the cameras display. This was very interesting to me for two reasons.1. It adds further support to my theory that the 2.8V LDO in the faulty Reveal Pro is likely causing the issue that I am seeing.2. A friend of mine with a Reveal Pro has a rolling noise issue on his unit similar to that seen if trying to record a CRT TV screen with a camcorder. It looks like a slow rolling shutter effect.I will have a good poke around the LDO with a portable scope today to see what is present on the supply rails. I am beginning to wonder whether there is a stability issue with the 2.8V LDO used by Seek Thermal and it has a penchant to oscillate if it is not adequately bypassed with good quality capacitors if the correct values. The TI datasheet for an LDO that I posted last night suggests 1uF low ESR MLC’s for the bypass capacitors. I checked before going to bed and I have some very nice Wurth 1uF 10V low ESR 0402 MLC’s in my selection boxIt could be that the camera would benefit from the installation of a better LDO in that position but that can wait until I am clearer in what is happening in my ‘patient’. I like inherently stable regulator designs.This all comes back to what I said earlier in this thread. When providing power to a microbolometer the designer needs to be very careful to ensure that the supply rail is very low noise. Any noise in the supply rail can act upon the analogue elements of the Microbolometer-ROIC combination and create noise on the output scene data. Separate digital and analogue regulated supplies are highly desirable, as found in many analogue/digital designs that require low noise levels in the analogue stages. In the Seek Thermal design I am seeing a budget solution for the Microbolometer supply rail. A RAW 3.7V to 5V SYS supply rail with very little filtering feeds a tiny LDO, that also has the minimum of filtering and noise reduction, and that LDO directly influences the noise performance of the Microbolometer. I would normally expect to see more filtering of the LDO output to remove as much noise from the supply rail as reasonably possible. Maybe I am wrong and Seek Thermal have selected an ultra low noise LDO that does not produce significant noise at its output ?Interesting stuff to me as I wonder how much, if any, random noise is injected into the Microbolometer in a Seek Thermal camera that appears to be working OK. This Microbolometer supply design may deserve further investigation. Sadly there is also the issue of noise created within the Microbolometer ROIC and that is beyond our reach to address.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 26, 2020, 11:32:43 am
content: Interesting article on reducing power supply noisehttps://www.electronicdesign.com/power-management/power-supply/article/21808839/3-ways-to-reduce-powersupply-noiseIt is not as simple as slapping a chunk of capacitance across a supply rail without first considering what you are trying to filter out of the supply and the appropriate specifications of the capacitor used. A combination of L and C filtration is what I would expect to see on the output of an common LDO supplying a Microbolometer. Some LDO’s are better than others when it comes to noise and stability. We could be seeing an unfortunate choice of LDO in my patients case.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 26, 2020, 11:57:44 am
content: I forgot to mention this earlier but when looking at Mikes teardown of a prototype Seek Reveal Pro he highlighted the presence of a Cortex M0 processor on the Microbolometer PCB and the mystery of why it was needed. Well there does not appear to be a M0 processor on my production Seek Reveal Pro Microbolometer PCB. I am wondering whether the Microbolometer PCB used in the prototype was the Circa 2016 Seek Thermal J3 Microbolometer PCB that is normally mated with the “603” processor PCB. In the “J3-603” configuration there is SPi control of the FFC shutter and a Clock generator on the Microbolometer PCB.Having an M0 processor mounted close to the Microbolometer would not be my choice of design so I am pleased that it appears to be absent in the Reveal Pro core. I wonder whether it has been moved/removed in the more recent Mosaic cores as well ?Could it be that early Reveal Pro cameras used the J3 microbolometer PCB and later versions of camera were fitted with the Mosaic Microbalometer PCB ?I note that the same LDO format and capacitor bypassing is present in Mikes core.Mike discusses the M0 processor at time index 21.40 in his teardown video....https://youtu.be/mgaBAm_sRnkFraser

author: Fraser
author_rank: Super Contributor
timestamp: July 26, 2020, 12:24:43 pm
content: A picture of the standard Seek Thermal (non pro) Microbolometer PCB used in the seek Reveal that was shown in the Hackaday teardown. Compare it to my picture of the Pro Microbolometer PCB.The same LDO is used..... is that a “Q” I can see on it ?Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 26, 2020, 12:46:10 pm
content: YayI think I found the identity of the LDOI believe it to be a Texas Instruments part.... LP5907A28YKMR as that is a 2.8V LDO with a marking of “Q”It is also an Ultra Low Noise part designed for sensitive analogue applications .... that fits its use in the Seek Thermal core perfectly. So they were trying to keep noise injection into the microbolometer to a minimumThe datasheet states that no “noise bypass capacitor” is required. Maybe the problem lies with the output MLC as 1uF is specified for stability.https://www.ti.com/lit/ds/symlink/lp5907.pdf?ts=1595767306668&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FLP5907%252FqualitySorry to detail every step in this investigation, but I hope it helps others when carrying out their own investigations. Note how a I am not diving in with the probes and test kit. That comes only when I understand the circuit that I am probing and what I should expect to see. In this case I will be looking for a signal that should not be present on the Microbolometer supply rail so it’s pretty simple. By investigating the circuit and identifying the components used, I can now determine what is failing and the correct replacement parts.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 26, 2020, 02:55:29 pm
content: Test complete on LDO output. Pictures attached.Low Noise LDO ? Hmmmmmm ...... nopeSignal is AC coupled to remove DC content. Pk-Pk measurement of the unwelcome signal is approx 200mVLDO specification added.Sorry about the awful pictures. These were just 'working pictures' for my use and I thought I saved proper pictures to the USB stick...... I have not used this particular DSO for some time and must have done something wrong as files saved, but no files found on the USB StickI might repeat the exercise again later but other pressing tasks are tearing me away from this investigation.Fraser

author: IwuzBornanerd
author_rank: Frequent Contributor
timestamp: July 26, 2020, 11:24:06 pm
content: Holy crap! That's 7% of full scale; does it show up as 20-30C of image noise?Perhaps that "Q" you see is actually a "C1"? The only regulator I found that matches the pcb pad pattern on the dongle units is an On Semi NCP114. Not sure if the marking on the part truly matches the specified marking, though.

author: Fraser
author_rank: Super Contributor
timestamp: July 27, 2020, 12:30:22 am
content: Hiya,I cannot remember the temperature error on the Faulty Reveal Pro measurements, but it was significant !Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 27, 2020, 12:34:35 am
content: I just checked the pictures of the faulty Reveal Pro.The measurements were jumping up and down due to the noise bars but as can be seen in the attached picture I was getting a reading of 70C when viewing an approx 20C ambient scene.Fraser

author: IwuzBornanerd
author_rank: Frequent Contributor
timestamp: July 28, 2020, 09:08:55 am
content: I'd say that is in the ballpark.Also, after perusing your TI regulator spec., I see that the "C1" marking on the regulator in my old XR matches the marking specified for the LP5907SNX-2.8/NOPB 2.8V regulator, so it looks like you found the right part.

author: Fraser
author_rank: Super Contributor
timestamp: July 28, 2020, 02:01:41 pm
content: Sadly other commitments are taking higher priority than the Reveal Pro as they are outside jobs and we have good weather at the momentIt would be soooo easy to just replace the MLC’s and even the Regulator IC as well but I want to get my DSO setup on it again to record the noise signal with proper earth connections and recording to the DSO flash memory stick for better quality images. I do this as a record of what can occur in these camera cores. I currently believe that the Regulator and MLC bypass capacitor at its output are causing the noise issue with the camera but until I have a well configured probing setup and later resolve the issue, I cannot be certain. I am in no great hurry anyway but like to record details of failures in case they assist others in the future.In the mean time, I found an interesting article reprint discussing the interaction of regulators and their associated bypass capacitors that is well worth a read. How many of us just deploy a regulator with a pair of bypass capacitors that we have always used, without considering the effects of this capacitors on the regulator ? I know I do ! I use LM78 series regulators with a couple of 0.1uF or 0.47uF polyester capacitors and think nothing more about it. What about paralleling bypass capacitors ? Is that a good idea ? Read on.........Part 1https://www.edn.com/why-bypass-caps-make-a-difference-part-1-how-a-regulator-and-its-output-capacitor-can-interact/Part 2https://www.edn.com/why-bypass-caps-make-a-difference-part-2-power-supply-excitation-and-ringing/Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 12:01:37 am
content: I set up the DSO and its probe to record the input and output signals of the LDO Regulator positioned on the Microbolometer board.The results are interesting but differ to those I captured previously. The previous test was 'quick and dirty' so was open to error. Maybe my probes 0V connection was not perfect ?Anyway, tonight I attached a nice solid 0V wire to the PCB for the probe to connect to and was able to capture decent snapshots of the noise on both sides of the LDO. I have yet to study the results but will upload them now for readers interest. Feel free to comment if you want to:) The noise on the output of the LDO is my greatest interest and and we need to consider the ROIC that is driven off of the supply rail and whether it is causing some of the supply rail signals that we are seeing. Anyway, here are the input and output signal captures. The probe was AC coupled and set to its X1 position for this test so all voltages are as declared in the images. The DSO software has a feature where it produces a list of measurements so I have included that for interest. It provides the Pk-Pk voltage reading. Do not get too involved in the other measurements as they are not really that applicable to the tests here. Time I was in bed so TTFN.Each picture is named as a LDO input or output. The first 4 are all Input captures whilst the rest are output.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 12:03:23 am
content: Now the Output captures.......

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 12:23:29 am
content: Just one more comment. If you look at LDO Output image 6 and check the period of the signal 'block' repetition you will find it to be around 62.6ms. That is around 16HzWe can guess that the signal is related to ROIC frame rate output (this is a >15fps PRO core). All food for thought.I have a feeling that this fault is not going to be as simple as I first thoughtAll good fun thoughFraser

author: IwuzBornanerd
author_rank: Frequent Contributor
timestamp: July 29, 2020, 01:28:44 am
content: I "wuzgonna" make similar comment. Now you know what that ">15Hz" means.My question is what is going on during that period of time when there is essentially no noise? If you take just the period of time where all the noise is and eliminate the gap you would get the 18fps that I get with the USB comm in a separate thread. So I wonder if all the noise is occurring during data transfer only & the processing time for the previous frame is the whole 62.5ms. But if there is no USB interface in that thing, why would the data transfer take so long?Watching you say it was time for bed & then half an hour later making another post tells me what I would be like if I had a stupidphone...Oh, while it's on, one more thing...

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 04:46:16 pm
content: OK readers, just like a Dick Tracey story.... we return for another thrill filled episode in the voyage of discovery that is the Seek Reveal Pro with noisy imaging(For youngsters.....https://en.wikipedia.org/wiki/Dick_Tracy)When I left you last, I had completed making decent DSO captures of the input and output of the LDO regulator that is positioned on the microbolometer PCB. As I previously stated in this thread, any noise on the supply rail to the analogue parts of the microbolometer/ROIC combination can lead to noise injection on the output image data. The question has to be, how much noise does it take to be a problem to a microbolometer and ROIC. The answer is... I do not know, but the less the better in my book. At this point I refer the reader to the previously posted specifications of the TI LDO regulator that I believe to be the one used on the Microbolometer core. The specified noise output is very small indeed and what I would expect from an Ultra Low noise LDO circuit. If you have read the article on LDO behaviour with noise bypass capacitors, you will also know that there is the risk of a noise prone output if the values of the bypass capacitors are not chosen with some thought. Failure of bypass capacitors can cause significant issues as the LDO is not designed to operate without their capacitance present at its I/O. The level of noise that I saw at the output of the LDO on the microbolometer PCB was surprising and a little puzzling at the same time. The Pk-Pk levels were up to around 100mV but the noise was not random oscillations of an unstable LDO, it was structured and it very quickly became apparent that the noise was a crib of the ROIC's activities with complete frames clearly discernable and the frame rate easily measured at 16fps. Hmmmm that was not expected and made me a little concerned. Such a signal would normally be heavily suppressed as modulating a power rail is a tad naughty. However, it is possible to modulate a power rail through inherent ac loading if the power rail is already in distress and has high impedance or poor bypassing. This I suspect could be our issue, rather than the less appealing thought of a failure in the ROIC structure. The fact that the core produces images suggest that the ROIC is still operating pretty well, albeit with noise bars.Today I cheated !Unlike many who might be attempting this sort of investigation, I am fortunate enough to have two other Seek Reveal PRO cameras. One is standard <9fps whilst the other is Fast Frame spec.Readers may recall that I previously stated that I purchased this sick Reveal Pro FF in order to learn about its design and behaviour. I did not fancy messing around with my brand new Reveal Pro FF as it remains mintNow a faulty unit at reasonable cost, that is something to play withNow that I had my DSO captures from the sick Reveal Pro, I thought it would be both interesting and helpful to take the same measurements on a healthy Reveal Pro. I could then compare the noise levels at the LDO to determine what was 'normal' in that region of the design. Now I did not want to mess around with my new Pro FF so I used the Standard <9fps Reveal pro instead. They should be very similar, or even the same after all ..... or are they ?Access to the Core on a Reveal camera is so simple. You just remove the two screws that retain the metal front casing section. The core may then be easily accessed or removedOpening another camera that is known to be healthy presents another opportunity, but one that must be used with great care ! It would be possible to test the suspect core on the known good camera mainboard and test the known good core on the sick cameras mainboard. This type of parts swapping is not without risk ! This is especially so if the two cameras are not identical hardware and firmware. Firmware can throw a wobbly or even be corrupted by parts swapping without thought. In my case I was concerned about the possibility of a <9fps camera mainboard somehow setting a frame rate restriction on a Fast Frame capable core. It was a risk and one I had to accept if I were to do the swap.The first set of pictures that I am going to upload here are of that core swap and the images produced. I will detail the DSO test results afterwardsFraser

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 04:49:58 pm
content: First the Suspect core connected to the known good mainboard. I fully expected a poor picture and potentially no picture as I am using a FF core on a non FF camera chassis !The results are below..... look for the tell tale noise bars and ignore the actual scene detail !

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 04:58:17 pm
content: Now the known good core attached to the sick cameras mainboard. Again, I was not expecting perfect images and potentially, no image at all.What I got was unexpected though ! The core initially looked like it would not produce an image...... but then as time moved on and multiple FFC events occurred, I saw a strange effect. I began to see a negative image. That is to say, although set to White Hot, I was seeing a hot coffee cup as black hot. then I saw why, the image was not updating until an FFC event. Wierd but I believe this is connected with how the FFC was operating on this <9fps core. More on that core in a minuteTo the pictures...... they were taken over a short period of time and the initial poor picture was replaced with the unusual inverted still images ! It looks like FFC is operating in reverse.Please note that initially the camera was looking at a pretty low Delta T scene of a cabinet against a wall. It was after I discovered the inverse image that I used the warm coffee cup as a target and set the colour palette to Iron.

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 05:08:07 pm
content: So waht about the frame rate restricted core ? Anything different about it physically ?Well yes, it is a different design of PCB to that in the sick Reveal Pro FF. Take a look at the attached pictures. The sick Reveal Pro FF core is already known to us from my previous pictures. The Standard frame rate limited Reveal Pro core is the type seen in Mike's teardown video and is equipped with an M0 processor ! The good news is that the LDO regulator is basically the same so any comparison tests for noise levels on the output should remain reasonably valid with the potential for more rail noise on the frame rate restricted core due to the presence of the M0 processor.I attach the comparison pictures of the two cores. The blue PCB is the Pro FF and the Green PCB is the Frame rate limited Pro core.

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 05:09:01 pm
content: More pictures of the frame rate limited Pro core.......

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 05:17:21 pm
content: OK, time for me to take a short break from the computer.So what did we discover from the core swap test ?Well I confirmed that the sick Reveal Pro mainboard is working without obvious issues. The image inversion is likely to be an incompatibility issue as I was using a standard core on an FF mainboard.The Fast Frame Core from the sick Reveal Pro displayed evidence of the noise banding when connected to the known good Reveal Pro mainboard. The core is where the problem lies and it is not some weird mainboard issue or mainboard supply circuit noise levels.So what will the DSO tell us about the noise levels that should be present on the power rails of a working example of the Reveal Pro camera core ?That comes in the next ''episode''Come back later for more ...........

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 05:57:05 pm
content: We return to the story dear readers........In the last episode we saw that the restricted frame rate Reveal Pro uses a different core PCB to that of the Reveal Pro Fast Frame model that I am working on. This could be just a revision related matter but, as Mike said in his teardown.... what is that M0 processor doing ?We also saw that the Core from a Fast Frame Reveal Pro cannot be just swapped with that of a frame rate restricted model.Most importantly for this investigation, we saw that the sick Reveal Pro FF core is most definitely the cause of the noise bars that are displayed on its host cameras screen. It is always nice to prove the location of a fault to avoid chasing a red herring !So what comes next ? Well, as I said, I repeated my DSO tests on the LDO regulator of the known good cameras microbolometer PCB. Despite the differences between the FF core and standard core, the noise level should be comparable in level. What follows are comparisons between the sick core inputs and outputs with those of the known good core. The image captures are named and the good core is ''StdCxxxxxx".Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 06:02:12 pm
content: LDO Regulator input Noise level comparisonsSick core first, then known good core.......

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 06:10:35 pm
content: Yes, surprisingly the healthy camera has higher noise levels at the input to its cores LDO regulator.So what about the levels on the output side of the LDO regulator ? I can say that it was a surprise..... I am off to enjoy a coffee and some cake so will upload the output waveforms soonWatch this space.....Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 06:20:42 pm
content: OK, drum roll please........ here are the comparison DSO captures of the LDO regulator output on each core. This is the important one. It defines what is 'normal' by using a known good core as a reference.As in the previous post, I will show the sick cores captures first, then the healthy cores captures for comparison........Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 06:27:47 pm
content: So is this test a joke or in some way wrong ? .... Nope, I was so surprised with what I saw that I tested, tested and tested again to confirm the readings. There was so little noise on the LDO output of the healthy core that I had to check the layout of the PCB around the LDO to ensure I was checking the LDO output pin.I think we can safely say that the noise levels present on the sick cores LDO output are not normal and causing the noise bars. So what is causing this high level of noise ? My money is on a failed LDO output bypass capacitor (cracked?)More from me when I have replaced the capacitors as that is the next logical move. If that does not cure the issue, I will need to fit a new regulator as the next step. After that I am faced with a failed ROIC which I hope it is not.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 09:10:05 pm
content: For anyone waiting to see the hidden side of the Reveal PRO FF core Microbolometer PCB, here it isI removed the PCB to inspect the Microbolometer bond wiresAs can be seen, not much to see and definitely no Cortex M0 processor hiding here.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 09:17:19 pm
content: Now the Core chassis rear detail.......

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 09:43:15 pm
content: Bond wire images. I checked them with a microscope but my camera just about sees enough detail. No issues were found with the bond wires.Why did I check them ? Simple..... exclude all reasonable possibilities before reaching for the soldering iron. There was the possibility of shorting adjacent bond wires or contamination/corrosion between them.It only takes a minute to check and is far better than feeling silly later for not doing so and finding an obvious issueBeen there, done that, got the T shirt !Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 09:43:54 pm
content: Second bond wire picture....

author: Fraser
author_rank: Super Contributor
timestamp: July 29, 2020, 10:12:29 pm
content: Now by this time I feel sure some readers will be thinking “why doesn’t he just fit a new pair of MLC capacitors and have done with this repair”. Well investigating the fault in this particular camera was not so much about Repairing it as quickly and efficiently as possible, but more of a journey into camera design and the collection of some useful information in the process of identifying the failed component. I hope my commentary also provides some insight into how I approach repairs on cameras for which I have no service information or schematics. Diving straight in and replacing any parts that ‘may’ be the cause of the problem can be a mistake, especially if you accidentally introduce additional faults in the process. Fitting components that are not the same spec as the original parts can also ‘muddy the waters’ if the system does not get on with their specs. By studying the ‘patient’ to a reasonable depth, you can often determine its needs where component specifications are being considered. This particular camera has a reasonable straight forward fault that I could likely diagnose, and determine whether it can be repaired, in less than an hour. I might be able to repair it in that time as well. But then where is the fun and learning in that eh? Sadly I also have very little time to spend on ‘toys’ so this investigation has had to fit into small time slots that are not ideal for reverse engineering PCB’s.All good fun for me though so I hope this ‘Saga’ is enjoyable to some readersFraser

author: IwuzBornanerd
author_rank: Frequent Contributor
timestamp: July 30, 2020, 09:14:22 am
content: If you figure 2.8V as full scale on the 14 bit ADC, then the LSB represents 0.17mV, and even the amount of noise you see on the output of the good unit is too much noise.

author: Fraser
author_rank: Super Contributor
timestamp: July 30, 2020, 10:59:15 am
content: Room for improvement possibly ?The LDO regulator noise spec is excellent so it is what has been done/not done on the a Microbolometer PCB that influences the higher noise levels present. A lack of suitably positioned bypass capacitors is a possibility, along with PCB tracks acting as inductors and excessive noise levels on the input side of the LDO. This could be an interesting little project for the future.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 30, 2020, 03:33:45 pm
content: Just ordered some LP5907 2.8V LDO regulators to play with. They are only 40p each and I still suspect I may need to fit one to the sick Seek Reveal Pro.I have decided to fit 2.2uF 10V X5R MLCC’s in place of the input and output bypass capacitors currently installed. With voltage derating considered they still retain plenty of capacity for their role. I will be adding an extra MLCC to the input side of the LDO to see if it lowers the noise at that point. I may add additional MLCC’s on the supply rail served by the LDO to see if noise from the Microbolometer ROIC can be further reduced.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: July 30, 2020, 09:01:53 pm
content: For those readers who have stuck with this thread so far...... I salute your staying powerTonight was the night of the soldering iron and it had work to do ! I was going to remove the suspect MLCC capacitor on the output of the LDO regulator and fit a nice shiny new Wurth 2.2uF 10V X5R part.This was only ever going to be a quick test as I was expecting disappointment and more work will be needed on this core.So the deed was done and the new MLCC was fitted. Those 0402 capacitors are little blighters.... if they ping out of the tweezers, they are gone for goodThe Gods were on my side today though and I got the little blighter soldered to the PCB on the first attempt. I would normally use a HAP (Hot Air Pencil) but the ground plane on this Microbolometer PCB is formidable ! The new MLCC is only fitted for this test so please do not look too closely at the soldering. It was about speed rather than a pretty fillet of Tin&Lead ! The Ground plane side of the MLCC was as challenging to solder as I expected. I had broken out a new sharp tip soldering cartridge for this task and it took a while to get the pad up to temperature. All came good in the end though and a usable pair of solder joints resultedWell did it make any difference to the fault symptoms ? I connected up the core to its host PCB and switched it on..... and ......... see the pictures for moreFraser

author: Fraser
author_rank: Super Contributor
timestamp: July 30, 2020, 09:02:51 pm
content: First Power on test after the new MLCC was fitted.......

author: Fraser
author_rank: Super Contributor
timestamp: July 30, 2020, 09:03:46 pm
content: The ubiquitous Coffee Cup test

author: Fraser
author_rank: Super Contributor
timestamp: July 30, 2020, 09:12:09 pm
content: As can be seen from the pictures.... normal service has been restoredThere is no interference present on the display and the scene images are great. The temperature measurement is now accurateThis camera had suffered the failure of one tiny 30 Cent component. I have that component safe and will test it. I suspect it has suffered a stress fracture and lost capacity.Well we got there in the end and the journey was fun for me. I have not finished yet though as I will properly rework the LDO section of the Microbolometer PCB and fit new 2.2uF MLCC capacitors on both the input and output sided of the regulator. I will then use the DSO to capture the noise levels at the input and output of the LDO for my record and to aid others on the forum.I have been reverse engineering the Microbolometer input to the mainboard and some other parts of it. That is a work in progress and is time consuming. A story for another day and another post me thinks.I will upload the pictures I captured on the Reveal Pro camera after repair in a minute for readers interest.The Argus 4 awaits my attention next in the queueFraser

author: Fraser
author_rank: Super Contributor
timestamp: July 30, 2020, 09:20:47 pm
content: OK, a before and after picture set from the patients memory........The ambient in the room tonight was around 24C

author: Fraser
author_rank: Super Contributor
timestamp: July 30, 2020, 09:24:40 pm
content: Other pictures taken by someone else before I got the camera.... just look at that noiseFraser

author: Fraser
author_rank: Super Contributor
timestamp: July 30, 2020, 09:34:47 pm
content: So I found the fault and it was as I had hoped, the output side bypass capacitor on the 2.8V LDO regulator. I was half expecting the fault to remain and the LDO to be faulty in some way but I am pleased that it was just the MLCC capacitor.This was actually a pretty simple diagnosis and repair...... they are not all so straight forward. The pattern of the noise signal present on the display just shouted "noise injection into the analogue front end" to me, so it was just a case of identifying the power supply rails and checking them. Some other less friendly faults are more challenging to localise and that is where the carefully managed approach to diagnostics often pays off. Diving straight in with a scope and soldering iron is so tempting to do, but is not always the best approach, especially when dealing with relatively high density PCB's and 0402 or smaller components !That is all for nowFraser

author: Fraser
author_rank: Super Contributor
timestamp: July 30, 2020, 09:43:44 pm
content: Just as a bit of trivia.... this whole investigation was carried out on our dining room table with simple tools, a relatively simple and inexpensive portable UNI-T UTD1102C DSO and a Fluke 87 III multimeter.The Pace soldering iron was only brought out to play once I had a good idea what my target wasYou do not need a sophisticated lab to repair many faults on thermal cameras. A methodical approach and simple tools is often enoughThere are the challenges of reworking large SMT devices and BGA types that require more sophisticated equipment of course ! I do not think my wife would let me place my Jovy 7500 IR rework station on the dining table somehowShe can be so unreasonable at timesFraser

author: Bill W
author_rank: Super Contributor
timestamp: July 30, 2020, 10:35:45 pm
content: Quote from: Fraser on July 30, 2020, 09:12:09 pmGood newsSurprised the capacitor came off in one piece, usually these cracked ones come away in two parts - at least it makes desoldering easier !Bill

author: Fraser
author_rank: Super Contributor
timestamp: July 30, 2020, 10:41:08 pm
content: Thanks Bill,I had expected the MLCC to fall apart as well ! I do not know what is wrong with it but a fracture seemed the most likely possibility as we all know how fragile they are. I will put it on my capacitance meter and see what it says about it.The capacitor took quite a lot of heat to remove it due to the efficient heat sinking effect of the ground plane. I will be removing both capacitors tomorrow and fitting new ones with great care as I take pride in my soldering, even if it will never be seenFraser

author: IwuzBornanerd
author_rank: Frequent Contributor
timestamp: August 01, 2020, 09:03:35 am
content: Congratulations Fraser! Yet another successful repair as well as a sweet deal on yet another toy you didn't need.

author: Fraser
author_rank: Super Contributor
timestamp: August 01, 2020, 03:39:15 pm
content: The MLCC replacement went OK but the heat sinking copper pour around the LDO regulator is a killer. It was soaking the heat away from the 0V MLCC pads very efficiently and I discovered that the PCB was designed to effectively couple thermally to the alloy chassis. This is actually a nice design that tries to keep heat from the LDO away from the microbolometer. It seems to do it pretty well from my MLCC soldering experience ! 0402 size capacitors, tiny solder pads and a decent heat sinking path makes for interesting rework !I am a perfectionist and one MLCC is not totally flat to the PCB on the 0V pad so I will be removing it, separating the PCB from its heat sink and reworking that MLCC. No DSO measurements yet as I will do those once I have finished the rework.Fraser