hybridfree/eevblog-posts huggingface dataset:
RE Technology RE-108 Signal Generator Repair Help Please - Page 1
Forum section: electronics / repair

author: ka5obi
author_rank: Newbie
timestamp: January 31, 2023, 12:46:02 am
content: The repair manual with schematics is here:http://www.peel.dk/RE/RE-108 Would not work when I went to use it the other day and I traced the problem to a dead 12volt power supply ProblemTraced it to shorted Tantalum capacitor in the Frequency divider II module which when replaced brought the signal generator back to life.When first tested after rebirth there was no output below 1.0 MHz. In the Frequency divider II there was what looked to be a bad diode(glass looked smoked) It was CR9on the schematic and so I replaced it. Now I have output below 1.0 MHz with the exception of 400 and 500 KHZ. I checked the input to the frequency divider II at J2 and I don't get inputs into Divider II when the signal generator is set to 700KHZ, 600KHz, 500KHZ and 400KHZ.I do get out put at the main out put on 600KHZ and 700KHz but there is nothing coming out when on the 400KHz or 500KHz settings. I am stuck here as I am not intelligent enough to know where to look next. Any help would be appreciated.

author: kawal
author_rank: Frequent Contributor
timestamp: February 02, 2023, 04:19:21 pm
content: Hard to follow your comments but seems to be an issue with the Divider I and maybe others.Can you draw on the diagram where you see and do not see signals ?Divider I needs to have a working divide by 10 section. That is the main suspect.

author: kawal
author_rank: Frequent Contributor
timestamp: February 02, 2023, 04:33:49 pm
content: Check around the 1:10 path Maybe dead divider chip or filter.

author: kawal
author_rank: Frequent Contributor
timestamp: February 02, 2023, 05:28:57 pm
content: Very strange issue . I thought maybe the Divider II is broken but all the frequencies you mention should be in the :16 leg.700kHz and 600Khz are for sure :16500khz needs to be coming from :16 as well.400kHz could be from :16 or from :32Maybe its capacitor C1 in the input of Divider II stage. If the cap lost its connection or cracked it could be passing HF but not low frequency.
Reoccuring error (749) on my HP 34970A - Page 1
Forum section: electronics / repair

author: jogri
author_rank: Frequent Contributor
timestamp: December 25, 2019, 12:23:44 pm
content: Hi guys,i've recently bought a 34970a, and nearly every time i start it it shows me error 749 (DMM relay count data lost). The service manual just says "if this error occurs, bring it to Keysight". Do you know more about this error or what causes it? I suspect it's the aging battery (i measured 2.8ish volts) since i get error messages about the time and date being lost when i don't power it up for a week.

author: Kleinstein
author_rank: Super Contributor
timestamp: December 25, 2019, 12:41:11 pm
content: The aging battery absolutely makes sense. The dead battery should be replaced anyway and chances are good this would also fix the error 749.

author: TheSteve
author_rank: Unknown
timestamp: December 25, 2019, 05:04:58 pm
content: It could also be the FRAM, they like to fail.

author: jogri
author_rank: Frequent Contributor
timestamp: December 25, 2019, 06:54:33 pm
content: I found this thread of another member having similar problems:https://www.eevblog.com/forum/testgear/hp-34970a-error-741-fix/Sadly, the error on my unit only comes up when the DMM module is installed, so i think the FRAM on the dmm module semi-died (the measurements are still bang on, it just displays this error message every time i start it). The battery is at 2.95V (it has a date code from 1999), i don't know why it lost the date and time.But as i don't have a programmer for the eeprom and a gpib adapter for reinitializing the new FRAM, there is nothing i can do to fix this error.

author: TheSteve
author_rank: Unknown
timestamp: December 26, 2019, 07:56:47 am
content: Quote from: jogri on December 25, 2019, 06:54:33 pmI guess this is your chance to buy an eeprom reader/writer. A reader/writer might be able to still read the full contents of the old FRAM. I know mine was bad in the 34970a but the TL866 was still able to read 100% of it correctly. I then wrote it into the new one and soldered it in.

author: jogri
author_rank: Frequent Contributor
timestamp: December 27, 2019, 11:53:39 pm
content: TL866 is on its way, do you know a good method to remove the glued FRAM without damaging it? Heating it won't work as it was wave soldered, do you know if Isoprop can soften it? I don't want to experiment with different solvents and risk killing the board.
Read and write old 82S135 and 82S126 PROM chips - Page 1
Forum section: electronics / repair

author: imperyal
author_rank: Newbie
timestamp: February 05, 2025, 04:16:00 pm
content: Hello,I have some very old ISA cards that are used on my mom's farm. These ISA cards are used to acquire data about temperature, EC, and pH for an irrigation system (running on an MS-DOS app and all).These cards failed me once, and I bought new ones, but now they are no longer available, so I want to be able to rebuild them if needed. I have working cards now, so I thought that I should back up the ROMs on these while I can.Each card has 2 82S135 and one 82S126 chips on it, with production notes on them.What kind of programmer/reader would be suitable for this?Thank you!

author: edavid
author_rank: Super Contributor
timestamp: February 05, 2025, 04:33:18 pm
content: Your best bet is to look for an arcade game parts specialist in your country, whatever it is. They will already have the equipment and blank parts available.Example:http://www.eprompro.com/If that's too expensive, you can easily make your own reader (e.g. out of an Arduino), and deal with the programming when you need to.

author: imperyal
author_rank: Newbie
timestamp: February 05, 2025, 05:33:36 pm
content: I will try the Arduino approach. In the future maybe I could use EEPROMs instead of PROMs, it should be possible right?

author: edavid
author_rank: Super Contributor
timestamp: February 05, 2025, 06:00:13 pm
content: Quote from: imperyal on February 05, 2025, 05:33:36 pmThere aren't any pin compatible parts, so you need to build adapter boards, and it can be tricky to make them fit, especially if you want to use DIP package EEPROMs. You also have to use EEPROMs that are fast enough.
Readable Service Manual HP4275A needed - Page 1
Forum section: electronics / repair

author: Aheld
author_rank: Regular Contributor
timestamp: May 14, 2024, 06:41:54 am
content: Hi Forum,I'm searching for a readable version of the Service Manual of HP4275A. Any suggestion is warmly welcome :-)The offical (old scan) version on Keysight homepage has a bad quality.In detail, I'm searching for the part to supply the DUT with DC voltage up to 200VDC and block this DC from the AC measuring signalBr.Axel
3D Scanner RealScan USB from 3D Digital Corp. Worth the time or trash? - Page 1
Forum section: electronics / repair

author: 3DcorpIsBankrupt
author_rank: Newbie
timestamp: April 04, 2023, 03:38:16 pm
content: Hey guys,you are so to say the last hope for a 3D Scanner I got from the scrapyard. Its a RealScanUSB 300 from 3d Digital Corp.Now I just have the unit and it appears to be working. Now the only problem left is, that the software is kinda unobtainable as far as I tried... And here in Germany they weren't very popular. The company who used to build these is bankrupt and hasn't left any information behind.So maybe anyone around the globe has ever worked with these and can tell me which software this thing needs to get to work?Otherwise this thing is not worth a dime
Realtek RTL8723BE PCIe wifi card is ready with coaxial connector - Page 1
Forum section: electronics / repair

author: abdulbadii
author_rank: Frequent Contributor
timestamp: May 14, 2022, 03:14:12 am
content: How do we have realtek RTL8723BE PCIe wifi card in Laptop can have antenna coaxial connector?

author: coromonadalix
author_rank: Super Contributor
timestamp: May 14, 2022, 01:49:07 pm
content: you have to use an U.FL to sma adaptor, theses cards will never have an sma connector ... unlees you try to solder one directly onto them (would be stupid and you could damage the card)Buy the cable from china, they cost nothing, bought many over the past yearsFor 10$ usd i had 2x cables and 2x antenna

author: KG7AMV
author_rank: Frequent Contributor
timestamp: May 14, 2022, 04:38:41 pm
content: Just use the right cable..Amazon get a few of them for a few bucks. or If you are in to salvaging you can find old routers some have the cable in them you could use alsoSMAhttps://www.amazon.com/HiLetgo-Wireless-Antenna-Extension-NRF24L01/dp/B01HXU1PKSNhttps://www.amazon.com/wlaniot-Pigtail-Wireless-Gateway-External/dp/B08ZXR8QDK/?th=1
Rebrands of Hung Chang 5804 oscilloscope - Page 1
Forum section: electronics / repair

author: ssschuh
author_rank: Newbie
timestamp: May 27, 2021, 02:00:03 pm
content: Hi all!I have been looking for HC-5804 manual/diagrams, to repair a unit I received recently.It has many defects, like no sweep, even with external source, and the dot is faint sometimes.For those problems, I can use the 5504 manual, for which the horizontal and z-axis circuits are the same.However, the 5804 has a CPU board, to control horizontal/vertical/sweep/storage modes via press buttons/leds in the front panel.But the circuit is in some locked mode, and I can't change any of those settings. I can't enable, for instance, ch2.The cursors are controlled by same board, and are working fine.To diagnose that circuit I'll need its circuit diagram.I couldn't find any portion of such manual/diagram.I suppose there may be some other rebrands of the HC-5804 with easier/possible to find manual.I could find some Beckman and Protek, but rebranding the 5602 instead, and others, not the 5804.Any help is appreciated!Thanks!
Rebuild  a Sencore TF30 Super Cricket - Schematic scan - Page 1
Forum section: electronics / repair

author: sampler1
author_rank: Regular Contributor
timestamp: May 15, 2023, 03:38:18 pm
content: Hi all,I picked up a Sencore TF30 Super Cricket and I have a good photo copy of the Service manual; problem is the schematic page has some Oscilloscope images that are blacked out due to a dark copy setting.If anyone has an original manual or some good scope images could you please upload them. MUCH Appreciated in advance !Cheers !

author: sampler1
author_rank: Regular Contributor
timestamp: May 21, 2023, 04:11:13 am
content: well i see no takers, anyone want to see the oem manual TF30?

author: Kim Christensen
author_rank: Super Contributor
timestamp: May 21, 2023, 04:23:34 am
content: I had to Google what a Super Cricket was andcame up with this.Not sure if the scope images are better than yours. Those are pretty terrible too.
Rebuilding a Feit LED Shop Light - Page 1
Forum section: electronics / repair

author: doolbneerg
author_rank: Newbie
timestamp: September 18, 2021, 08:04:39 am
content: I got a Feit LED shop light,https://www.feit.com/product/4500-lumen-4000k-4ft-led-utility-light/,from a friend because they spilled water on it and let out the magic smoke...I have been working through most of the components identifying them and testing them. However there is a small IC on the board, which I believe to be the brains of the regulator on the board and am trying to figure out if I am able to get one of those. It is clear that the chip is dead, one pin melted off.It appears to have the text "9486T 98X0" written on it and it appears to be a SOT-23-6 package.I haven't dug too deep into the schematic yet, but it appears to be a buck regulator in a current source configuration.Any ideas on how I might be able to figure out what this IC is? And a suitable replacement for it?
Rebuilding lead acid battery cells with negative plates, how to oxidize the +? - Page 1
Forum section: electronics / repair

author: Dehv
author_rank: Contributor
timestamp: March 30, 2022, 10:08:26 pm
content: Ive got a 20 year old lift truck battery for my off grid house.Safety warnings aside for this thread, how might one convert a set of good neg plates to red lead without repasting the half element?Hydrogen peroxide bath?Ideas?
Recalibrating a clamp meter wavetek AC68 - Page 1
Forum section: electronics / repair

author: NRP_SANTOS
author_rank: Newbie
timestamp: March 23, 2021, 04:17:07 pm
content: Hello, I'm trying to recalibrate my clamp meter (a wavetek AC68). I can't seem to find a schematic online and on the manual it says nothing about recalibrating the meter.There are some trim pots on the pcb of the meter, is it ok to try to adjust them one by one to identify what trim pot adjusts what function? I don't want to kill my meter thoroughly as I still want to use it.

author: Kleinstein
author_rank: Super Contributor
timestamp: March 23, 2021, 05:23:42 pm
content: Depending on the meter, the position of trim pots can be relatively tricky, and it could be hard to get the old good position back without instructions on how to do the trimming.Usually the clamp meter part should not need extra calibration the turns ration is a fixed number and should not drift over time. It depends on the circuit on the secondary side - this may be a normal current range, if they are present for lower currents.Before changing the trimmer I would take a good look at the circuit to know what the trimmers are good for. So kind of a crude revers engeniering. This may be needed even more to correct a lost setting if it was a wrong trimmer.

author: shakalnokturn
author_rank: Super Contributor
timestamp: March 23, 2021, 06:54:17 pm
content: How far off is it and on how many ranges / functions?Usually if more than one function is off it's the Vref for the ADC that has drifted.Often enough there's no separate trimmer for Ohms so you'd start by checking / adjusting ohms to get Vref right.Look for the datasheet to the ASIC if available usually that will give you some ideas on what trimmer does what.Edit:If you're tempted to just fool around with the trimmers you can measure their adjustment with another meter, make sure to note the polarity and position of the function switch in the clamp meter.

author: NRP_SANTOS
author_rank: Newbie
timestamp: March 23, 2021, 10:06:09 pm
content: error 10% Functions ADC and AAC only.
Recapping 20-year old BMW car audio amplifier - Page 1
Forum section: electronics / repair

author: Fried Chicken
author_rank: Regular Contributor
timestamp: September 02, 2024, 03:00:10 pm
content: I'm not sure if itneedsa recap, but I have a cheap parts unit, all the tools, and the capacitors themselves are cheap.The unit is from 2003 so about 20 years old, made by Harman Becker according to the PCB, Harman Kardon according to BMW's marketing.The issue is I can't find the capacitors.They're all rated for 105°C.I'm seeing "SXE", "LXY", one Rubycon, and a whole bunch of "KME" which I believe is United Chemi-Con but no longer manufactured.It's one of the most beautiful PCBs I've ever seen. The glue has held up beautifully, the case is some like forged powder coated steel. It's so good. So so good.Anyway, I have two approaches I feel I can take. 1. find a cross referenced matching capacitor (I'm not sure how). 2. Find capacitors that meet the known spec with everything turned up to 11 (low leakage, low ESR, highest life rating, most expensive, etc.)Help with this would be appreciated!

author: jpanhalt
author_rank: Super Contributor
timestamp: September 02, 2024, 03:53:59 pm
content: Does it work? Why "recap," if it does?

author: wasedadoc
author_rank: Super Contributor
timestamp: September 02, 2024, 04:17:38 pm
content: While it is true that capacitors handling high ripple current do age, get tired, dry out etc I don't find that a general "replace all electrolytics" is usually warranted. The smaller ones on that board will be audio coupling or supply decoupling. I have audio gear much older than 20 working fine with original through hole electrolytics still in place. Those little round can SMD electrolytics are a different story.Though some scoff, those $10 transistor testers are amply good enough to (out of circuit) test if loss of capacitance or increased ESR warrants a replacement.If you do decide to replace you do not need make for make, type number for type number.As an aside KME can mean Kyushu Matsushita Electric, part of the group now better known for the Panasonìc brand name.

author: Xena E
author_rank: Frequent Contributor
timestamp: September 02, 2024, 06:28:51 pm
content: Unnecessary blanket re-caps arethenumber one reason for the trashing of vintage electronic gear.Yes, electrolytics can and do fail, but on the amount of hours that your HK is likely to have run, it's unlikely to have worn them out.How do you know the new ones will be any better?X

author: Jeff eelcr
author_rank: Frequent Contributor
timestamp: September 02, 2024, 10:23:49 pm
content: If the caps do not show signs of physical leakage and no snap, crackel, or pops and the amp has good audio then for now, they work ok.It all comes down to time and tempature for failure, garage kept or sits outside sun/shade, how long etc.Size of caps can make a difference, larger 7mm and up outlast 5mm but different caps fail in different ways.Jeff
Reccomendation for DMM Calibration Service in San Diego or Orange County area ? - Page 1
Forum section: electronics / repair

author: hvontres
author_rank: Contributor
timestamp: January 19, 2023, 07:24:11 am
content: I am looking for recommendations for a reasonable calibration service for a HP 34401 DMM in the San Diego or Orange County areas. I recently got one off of ebay. The outside is a little rough, but some performance testing against another 34401 from work didn't show any glaring errors. I would like to be able to use it as a transfer standard for doing home-gamer level calibrations on some of my other gear (Tek 744a, hp 3314a and eventually my 8642a)
Recognise this tactile switch? - Page 1
Forum section: electronics / repair

author: Audiorepair
author_rank: Frequent Contributor
timestamp: October 06, 2021, 11:37:37 am
content: It's from a Nord Keyboard, but hopefully will be somewhat more generic and available somewhere.

author: Audiorepair
author_rank: Frequent Contributor
timestamp: October 06, 2021, 07:10:09 pm
content: Found them.https://www.mouser.co.uk/c/electromechanical/switches/pushbutton-switches/?m=Marquardt&series=6450Funny, Google on a PC today didn't find it, Mac mini at home did.Or it's probably just me.
recognize component and diagnosis - Page 1
Forum section: electronics / repair

author: Daxxin
author_rank: Regular Contributor
timestamp: April 12, 2020, 05:24:08 am
content: hi here bottom of mobo pcb got troubles with boot look at this component and pls help to discover cause of this.

author: coromonadalix
author_rank: Super Contributor
timestamp: April 12, 2020, 05:29:57 am
content: If a part explose like this causes could be wrong polarity, excessive voltage, short circuit, bad manipulation, static discharge, part who has failed ??Many things can happenWhat is this board ? a tv a monitor ? model, brand needed we are not magicians, we need more detailsWhat happened, and take a bigger photo of the damaged part, cant see the part number

author: bob91343
author_rank: Super Contributor
timestamp: April 12, 2020, 05:38:31 am
content: Well it's U23 so look in the parts list. Maybe it's a voltage regulator.I recently found a burned resistor in a voltmeter. I replaced it and solved that problem, but analysis shows that the resistor had to be defective because there was no mechanism for it to overheat. It had changed from 100 Ohms to several thousand Ohms and was in a constant current circuit.

author: helius
author_rank: Super Contributor
timestamp: April 12, 2020, 07:01:10 am
content: Is it NJM78L10A? 10V LDO regulator
Recommend me a residential Sydney Electrician?? - Page 1
Forum section: electronics / repair

author: HashAsh
author_rank: Newbie
timestamp: December 01, 2023, 03:58:02 pm
content: Hi.Didn't know which section to post this, but can someone please recommend an awesome pro, by the books, Sydney western suburbs licensed electrician for a whole house switchboard & box replacement ?? Someone really experienced who does it for a living & not just a hobby. Anyone really happy with their experience from around here & would like to share?I've had some shitty experience before so I thought why not ask here, where there's a lot of pros. It's kind of overwhelming just blindly searching the net & hoping for the best, it's really a lotto for me.Thanks!

author: BlownUpCapacitor
author_rank: Frequent Contributor
timestamp: December 01, 2023, 07:32:48 pm
content: You can try posting this in the "JOBS" section of the forum.
Recommendations for low-cost BGA removal/reball service? - Page 1
Forum section: electronics / repair

author: jayk
author_rank: Regular Contributor
timestamp: March 13, 2024, 04:53:20 pm
content: I have a couple of board with some large FPGAs (~1K pins) I'd like to have removed and re-balled. Can anyone recommend a vendor who could do this (preferably US-based, but could possibly send overseas)? This is hobby stuff, so not looking to spend a fortune.

author: CaptDon
author_rank: Super Contributor
timestamp: March 14, 2024, 02:19:57 pm
content: Define your problem a bit more. Are you just harvesting some expensive or hard to get devices, or is your board failed and you want to reflow the old chips to make your board work again? Re-Balling of a chip with that many pads will probably be a waste of time at best. As Rocky used to say to Bullwinkle "That trick never works". Successful removal, re-balling and crude failure rate when reflowing the parts is probably money wasted unless the parts are valued at over $500.00 each. I have been down this road with contract manufacturers and financially the outcome is never positive nor is the reliability after 6 hard hot/cold thermal cycles in the chamber!! You end up shipping questionable junk to your customers and getting bitten in the ass (or fired) six months down the road of field failures when I stand in front of the engineering group and say "I told you this was a bad idea". Your only real option, and it'll cost, is to contact local 'board house' contract manufactures who are specialized in surface mount techniques. Anything less is 'less'.

author: J-R
author_rank: Super Contributor
timestamp: March 16, 2024, 05:41:50 am
content: I've been watching this guy on Youtube for a while; seems legit:https://www.youtube.com/@northwestrepair

author: Haenk
author_rank: Super Contributor
timestamp: March 16, 2024, 10:00:40 am
content: Quote from: J-R on March 16, 2024, 05:41:50 amHe could probably do it. But: reballing thousands of balls is certainly no fun and will take a long time; even more so if no masks are available.lots of work * high skill level = very expensive, aka "fortune"That would certainly only make sense if the FPGAs are in the multi-k-USD range - but then you will have nobody to who would buy them. How often can you reflow them? Twice? A commercial buyer will stay away as there is no documented history and uncertified rework - and a private buyer won't pay a lot of money.Probably there is a reason why there are many cheapish-cards with FPGAs on ebay.
Reconnecting a hot air station heating element - Page 1
Forum section: electronics / repair

author: Tinynja
author_rank: Newbie
timestamp: June 28, 2021, 01:11:02 am
content: Hello, after a year of infrequent use, my chinese hot air station (Sumsour 858D) finally died on me. Fortunately it seems the problem isn't too serious: the heating element came undone from its wire.Now i'm wondering how do I get them back together? After some research I understood that soldering them would be a bad idea since it would probably melt once i turn it on...How would you go about resolving this problem? Any help is appreciated! Thanks

author: bob91343
author_rank: Super Contributor
timestamp: June 28, 2021, 02:06:07 am
content: The ideal method is to spot weld the parts together. The element gets too hot for solder, and the part is too small for the use of a clamping screw.Perhaps you can spot weld by discharging a capacitor.

author: coppercone2
author_rank: Super Contributor
timestamp: June 28, 2021, 04:31:56 am
content: i would fix this with a parts replacement, old resistance wire is junk

author: bob91343
author_rank: Super Contributor
timestamp: June 28, 2021, 06:27:18 am
content: Replacement elements are available. Or they were. Be sure the replacement is rated for your power line voltage.

author: RoGeorge
author_rank: Super Contributor
timestamp: June 28, 2021, 07:12:28 am
content: If there is enough space you can twist together the broken pieces. It won't be reliable for long term, but might help finish the work for the day.Replace the heating element with a new one, and buy one or two more for spare. The heating element is some sort of consumable, like a light bulb is for a house.

author: perieanuo
author_rank: Frequent Contributor
timestamp: June 28, 2021, 09:21:25 am
content: well, cheap romanian-like solution is finding small copper pipe (from some pen with this type of element inside), cleaning the 2 ends of your interrupted wire, inserting them into the pipe and crimp the thing. can work for years if well done, i wasn't born like today with spare parts from china/usa/moon etcaeteraor replace the elementif your pocket allows it
Record Player Electrically "Noisy" Even When Powered Off - Page 1
Forum section: electronics / repair

author: m002922
author_rank: Newbie
timestamp: January 01, 2022, 06:37:31 pm
content: So since this repair . . .https://www.eevblog.com/forum/repair/record-player-missing-capacitor-slow-to-start/msg3868739/#msg3868739(maybe it was there before and I never noticed, definitely possible) I've noticed the record player has a very noticeable electrical hum, even when powered off, but not when unplugged (OK, obvious, but I thought I would say it). The record player is grounded (in the way that record players are grounded - a separate wire you attach to the receiver), the plug is a two prong (like every other player I have), not three prong.Any advice (to include "watch this video dummy" - or this has been covered a 1000x - though I did look) on where to look for the source of the noise? I can live with it, but just curious if it is something I can fix (or perhaps something caused by the new capacitors).Thank you in advance.

author: abdulbadii
author_rank: Frequent Contributor
timestamp: January 03, 2022, 09:33:04 pm
content: Have grounded the prepared ground pins on back (to amp first if any)?

author: commongrounder
author_rank: Frequent Contributor
timestamp: January 04, 2022, 03:59:18 pm
content: When you say hum, do you mean a mechanical hum sound emanating from the chassis? Many of these turntables have mains transformers that are connected to mains power all the time. Power switching for the motor and other circuitry takes place on the secondary side. The transformer itself will emit a constant mechanical hum noise from the windings as long as the unit is plugged in. Often you’ll notice the transformer has rubber mounts to reduce the vibration transmitting to the platter and on to the pickup while playing a record.
Recovering data from a (dead?) OCZ Vertex 460 that isn't detected now - Page 1
Forum section: electronics / repair

author: darkpowrjd
author_rank: Newbie
timestamp: September 16, 2020, 05:30:30 am
content: Registered here after seeing there being a few other posts being made about these drives and problems people have had with them, so I am hoping I can get some help with my drive.I have an OCZ Vertex 460 (250GB) that I've ran Windows 10 on for some time. It's only until recently that I found out that the random disconnecting is not just something that happened to me on several occasions. This is because the drive finally decided that it had enough and just not start at all. I have since replaced the drive, but now I'm faced with a huge issue: the OCZ one has some rather important things on it (not as in personal pictures or info on it, but stuff that I would need to spend a lot of time remaking if I were to not be able to get the made files off of the OCZ drive).The drive I bought came with a cable that I could use to plug my old SSD drive into a USB port (has the SATA connectors on one end, and a standard USB plug-in on the other). I'm trying to get the drive to be recognized in this way, but the drive is now refusing to connect to anything (even another computer). I don't know if it's the same problem of it being a dead or near dead drive or the way I'm trying to connect it to my computer right now. I just want what is on this drive, assuming the drive didn't get wiped, to be recovered so I can get it onto the new drive.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: September 16, 2020, 05:35:31 am
content: I'm not sure if I'm any help but I keep a dead OCZ vertex 2 60GB which let me down in the worst possible way on the monitor stand to remind me never to buy a OCZ drive ever again.
recovery disk for Agilent dso81204b with m-880 nitro motherboard - Page 1
Forum section: electronics / repair

author: super_electron
author_rank: Contributor
timestamp: October 01, 2023, 07:20:57 am
content: Hi, I am looking for hard-drive recovery disk for an Agilent dso81204b with M-880 Nitro motherboard from ADLINK. Any links to download either the hard-drive image or recovery disk or Agilent/keysight's FTP site link for the ISO will be greatly appreciated?thanks'
Recplace axial capacitor by radial cap? - Page 1
Forum section: electronics / repair

author: nightfire
author_rank: Frequent Contributor
timestamp: February 13, 2021, 11:20:52 pm
content: As a newbie to repairing old stuff I am in the progress to make some homework before I will in the next weeks plan to recap some old equipment.Here I have some stuff that originally uses axial electrolytic caps, but my favorite supplier does not carry exact replacements for them.Question is here: What are the drawbacks of replacing some old capacitor with a new radial one?I could think of vibration (may be fixed with some glue or goop or similar stuff) and issues to get the wires right because of the space the former axial cap has used...Are there other issues like heat dissipation, different ESR or other things I would have to be on the lookout?(My supplier carries Panasonic caps that I would like to use, and a DER EE DE-5000 is just ordered to check for good components)

author: bob91343
author_rank: Super Contributor
timestamp: February 14, 2021, 04:22:05 am
content: I think the capacitors are the same, or so close that you don't have to worry. Of course the radial is a cantilever and needs support to avoid fatigue of the leads. Cementing it down ought to be okay. Use silicon rubber or a clamp if it's heavy.

author: james_s
author_rank: Super Contributor
timestamp: February 14, 2021, 04:39:47 am
content: It looks a bit sloppy and often one of the leads won't be long enough but if you can make the thing fit and mechanically secure it there is no problem.
Recuperation files on SD Card - Page 1
Forum section: electronics / repair

author: GGMM
author_rank: Frequent Contributor
timestamp: June 18, 2025, 06:58:29 pm
content: Hello,Suddenly my phone showed me that my SD card is no longer readable.Despite the fact that I have saved pictures, I wanted to test SD card recovery applications.I tested several, it works and finds me my pictures..... but unfortunately requires a few money euros or dollars to really retrieve it.It’s a bit disappointing for a single use.Question: Do you know one who does the work until the end, you understood it, for free.cdt

author: thephil
author_rank: Regular Contributor
timestamp: June 18, 2025, 08:26:27 pm
content: I have usedrecoverjpeg(https://github.com/samueltardieu/recoverjpeg) with success in the past. but I believe it's LINUX only.

author: Koray
author_rank: Regular Contributor
timestamp: June 18, 2025, 09:48:39 pm
content: Recuva for windows works great.

author: GGMM
author_rank: Frequent Contributor
timestamp: June 19, 2025, 06:15:45 am
content: Koray,I tried Recura for windows this morningNot possible, it's said: Failed to scan the following drive E:unable to determine the file system typeWith EaseUS, Coolmuster, recoverit, they find the files (30/45 mn of work), but no recovery if no licence.a solution?cdt

author: Haenk
author_rank: Super Contributor
timestamp: June 19, 2025, 07:02:27 am
content: Use TestDisk or PhotoRec.https://www.cgsecurity.org/

author: GGMM
author_rank: Frequent Contributor
timestamp: June 19, 2025, 01:42:31 pm
content: Haenk,It worked with photorecoveryThe interface is not entirely graphical, it’s the result that counts.Thank you againcdt
[SOLVED] Red varnish-glue for locking screws and bolts, electronic glue - Page 1
Forum section: electronics / repair

author: electr_peter
author_rank: Unknown
timestamp: February 09, 2022, 08:08:53 am
content: I need some external locking solution for small screws/bolts. I have seen a thread on EEVblog before but can't find it anymore.It is semi-transparent substance, red in color glue (like honey), put on screw/bolts externally to mark that they are locked and prevent them from loosening (or at least mark loosened ones). Easily removable. Household equivalent is red nail varnish. It is not locktite for internal threads, that's a different thing.How is this substance called and where to get it?

author: Audiorepair
author_rank: Frequent Contributor
timestamp: February 09, 2022, 08:16:53 am
content: "Anti tamper" is one such product.Not sure how effective a thread locker it is, but ok to seal presets against vibration.https://uk.farnell.com/electrolube/blr10sl/adhesive-antitamper-red-10ml-syrge/dp/1841559?st=tamper

author: jpanhalt
author_rank: Super Contributor
timestamp: February 09, 2022, 08:17:25 am
content: Are you looking for "anti-tamper" indicator? Many manufacturers. Here's one:https://www.newark.com/electrolube/blr15ml/sealant-bottle-15ml-red/dp/44AC2379

author: electr_peter
author_rank: Unknown
timestamp: February 09, 2022, 10:05:09 am
content: Thanks for suggestions. I think I found right search terms.Anti-tamper seal products become hard and brittle, like nail varnish. I was after something softer like "electronic glue" or "threadlocking adhesive silicone sealant". "Kafuter K-200R" product fits the bill, it will limit loosening of screws.

author: Oilngas
author_rank: Contributor
timestamp: February 10, 2022, 03:08:15 am
content: Perhaps you are thinking of "Glyptal".http://www.glyptal.com/products/1201tech.pdf
Reducing rattling PWM noise of a fan - Page 1
Forum section: electronics / repair

author: AndreyS
author_rank: Regular Contributor
timestamp: August 19, 2023, 07:27:58 pm
content: Hi there, I'm having a lab power supply with very annoying fan noise. First I thought its noise comes from dislodged axis or lubrication dried out, but in fact the noise comes from coils. Here video demonstration:https://streamable.com/q4cqt7Googling the issue has led me to this articles:1)https://ww1.microchip.com/downloads/en/appnotes/00771a.pdf2)https://jgaurorawiki.com/a5/remove-fan-pwm-noiseTo sum up, the solution would be to solder ceramic capacitor across base-emitter of the transistor. In my case there are two transistors in darlington configuration. To which transistor should I solder a cap? I'm quite confused.Or maybe you've got a better idea how to deal with this?

author: benj38
author_rank: Frequent Contributor
timestamp: August 19, 2023, 07:48:49 pm
content: I have not looked at the articles you included, nor am I commenting on the effectiveness of the proposed solution of adding a capacitor.My comments are of general nature:1. A Darlington pair is usually treated as a single transistor, as far as the rest of the circuit is concerned; you should consider its emitter to be the emitter of the transistor that isnotconnected to the base of the other transistor. The collectors of the two transistors are tied together and make up the Darlington's collector.2. Why don't you just try and see what works? it takes less than 20 seconds to de-solder the capacitor and solder it again to another location in the circuit, so just experiment! You can hardly damage anything by testing these different locations.

author: AndreyS
author_rank: Regular Contributor
timestamp: August 19, 2023, 07:58:30 pm
content: i should have clarified some things:15V 0 15V ac goes into bridge rectifier than into 7815 and 7915fan (24V) is driven by ne556n (dual bipolar timers).The thing with experimenting, I just must not mess up. Thus seeking some guidance from you eevblog forum users

author: Gyro
author_rank: Super Contributor
timestamp: August 19, 2023, 08:40:40 pm
content: If it helps, I fixed a similar fan PWM rattle on my GW Instek GPS-2303 PSU using a fairly basic RC filter...https://www.eevblog.com/forum/repair/cured-my-gps2032-psu-rattle/

author: fmashockie
author_rank: Frequent Contributor
timestamp: August 20, 2023, 06:47:41 pm
content: Is this device under test something you are building or an existing device that recently started exhibiting this symptom? If the latter, I don't think you've ruled out a bad fan as the cause. The second article you shared even mentions that filtering the PWM would not fix the issue if it is caused by a bad fan. So again, if it is the latter, I would try replacing the fan first.
Reflecta / Wolverine / Somikon 8mm Scanner "please recheck films place" fix - Page 1
Forum section: electronics / repair

author: Gulftown
author_rank: Regular Contributor
timestamp: September 13, 2025, 06:10:37 pm
content: Hi,i have a Somikon Super 8 / 8mm scanner which constantly showed the "please recheck films place" error message while scanning.Normally this should only happen, when the film is stuck and the stepper motor is loosing stepps with a noticable noise.Mine did it without a stuck film every few minutes and i found a lot more videos about it on the internet but no fix.I figured out that the transport sensor in the machine has a very small tolerance and mine was off due to wear on the cog thats controlling the transport.I scoped the trigger pulse and it was super small and not sqare as it should be.All i had to do was to bend the sensor a litte bit up, so the plastic of the transport correctly blocks the light of the ir sensor. (sorry for the picture)Now the sensor signal is sqare again and the scanner is working flawlessly again.I just post this here for anyone in the future trying to repair this kind of scanner
Reflowing/reballing a GPU core - Page 1
Forum section: electronics / repair

author: MarkC
author_rank: Newbie
timestamp: November 21, 2024, 05:53:47 am
content: I have my first GPU core to reflow/reball and I am seeking advice on the equipment. About a year ago I got myself an Atten 862D and learnt how to do memory IC's and smaller BGA packages but I am aware that it alone will not do a core.So, do I just need a good preheater and the hot air will do the rest or do I need to invest in an IR rework station? I don't mind buying an IR station if they are needed but are they needed? Thanks all.

author: Harry_22
author_rank: Frequent Contributor
timestamp: November 21, 2024, 06:30:09 pm
content: Hello!Good approach!Yes you must have a bottom preheater.A Z-axis platform and an infrared pyrometer would also come in handy.I think if you set the temperature correctly and transfer the heat to the soldering area, then nothing else matters.To do this, it would be good to understand the basics of thermodynamics.My colleague uses the minimum set. And doing very complex work. All depends on the experience that you will undoubtedly gain.Attached is a video of him rolling balls.https://youtu.be/DVTxHx0z-wo?si=86rTudL4U7HKT8qvPSCould you attach the photo of your board to understand the dimensions.

author: electronix27
author_rank: Contributor
timestamp: November 22, 2024, 12:42:00 pm
content: Check out this fella's website, he does all sorts of these type of repairs, with more than one type of re-balling method.https://www.youtube.com/@dosdude1

author: keymaster
author_rank: Regular Contributor
timestamp: November 22, 2024, 06:36:04 pm
content: Another good source for gpu repairs and gpu reballing video is northwestrepair (https://www.youtube.com/@northwestrepair)
REL Q201E and Rotel RKB-8100 service manuals - Page 1
Forum section: electronics / repair

author: rfengg
author_rank: Regular Contributor
timestamp: January 31, 2024, 07:29:22 pm
content: Hi there,Both my REL Q201E and Rotel RKB-8100 died in the terrible storms we had last month....not sure if this is a coincidence?Any pointers in terms of the service manuals/schematics to either of them as searching the web has come up with nada results?thanks

author: rfengg
author_rank: Regular Contributor
timestamp: April 09, 2024, 08:23:13 pm
content: Hi there,Finally managed to get onto the REL Q201E repair after a big move across the country and into NY.It seems that the REL Q201E uses the IRF240/IRF9240 pair in push pull and there are in total 2 pairs of the IRF240/IRF9240.Sure enough, a pair of these have failed dead short but the mains fuse is intact.......are the two pairs of the IRF240/IRF9240 paralleled or bridged for the subwoofer?I was not able to get hold of a schematic but the 4 ballast resistors are all fine as well.Any advice on what other things to check before installing the new IRF240/IRF9240 pair?

author: rfengg
author_rank: Regular Contributor
timestamp: April 15, 2024, 02:20:36 pm
content: The REL Q201E sings again.....what I had anticipated to be a difficult repair , turned out to be one of the easiest repairs ever.One pair of the IRF240/IRF9240 were sho(r)t , but I did change both the pairs in the amp just to be safe.($6 a pair from Digikey)The amp circuitry is quite simple and anyone with issues on the Q201E should be able to sort it out quite easily.The driver is a beast and these REL's are worth repairing as I was really impressed by the LF oomph.
Relpacing a Thermistor on 3D Printer hotbed? - Page 1
Forum section: electronics / repair

author: kazzle101
author_rank: Contributor
timestamp: June 03, 2025, 09:15:41 pm
content: HelloThe NTC Thermistor on my Anycubic Kobra Neo appears to have died, I get a "MINTEMP triggered, system stopped! Heater_ID: bed - Printer halted. kill() called!" error.With it disconnected from the controller board, I get a reading of around 100K and the resistance drops when I warm it up with my fingers, according to Anycubic I should be getting a reading in the region of 10K:https://wiki.anycubic.com/en/fdm-3d-printer/kobra-neo/kobra-neo-err--please-resetI can't see any markings on the NTC itself. Will replacing this with a 10K NTC fix the problem? Such as one of these:https://www.ebay.co.uk/itm/172602710821?_skw=10k+ntc+thermistorThanksKarl.

author: benj38
author_rank: Frequent Contributor
timestamp: June 03, 2025, 10:04:47 pm
content: Quote from: kazzle101 on June 03, 2025, 09:15:41 pmThe problem is that the resistance at 25C (which is what the 10K stands for) is not the only critical parameter defining an NTC thermistor. At minimum, you also need to know the B-value of the thermistor.I will not try to explain the exact meaning of the B-value (and in fact, there is more than one B-value for a given thermistor, since ideally it is a constant, but in practice it varies a bit with temperature), but intuitively it is a number describing the response of the thermistor to temperature changes. In other words, you can have two 10K NTCs, that will both measure 10K at 25C, but at say 100C will measure quite differently since they have different B-values.

author: thm_w
author_rank: Super Contributor
timestamp: June 03, 2025, 11:07:40 pm
content: The page you linked says 100k not 10k, so your thermistor is fine.You need to trace the wiring from the thermister back to the main board, good chance there is a broken wire or bad connector, etc. along the way.100k is a normal NTC thermistor value used in 3D printing, 10k is not commonly used.

author: Kean
author_rank: Unknown
timestamp: June 04, 2025, 07:32:18 am
content: Yes, at approx 25C ambient it should measure 100KΩ ±10KΩIf you measure about 100KΩ, then I doubt it is the thermistor at fault - probably the wiring.

author: kazzle101
author_rank: Contributor
timestamp: June 04, 2025, 05:09:54 pm
content: HelloYes it was the cable, I was overthinking the problem and mis-reading the Anycubic web page.I've now replaced it and all is working again.Thanks.Karl.
Remote Control Batteries Lasting a Day - Page 1
Forum section: electronics / repair

author: Chet T16
author_rank: Frequent Contributor
timestamp: January 02, 2024, 10:43:52 am
content: Hi All,I've a remote control from a NowTV/Roku that is using up its 2xAAA batteries after a day. Other than that its working fine. I've taken it apart and there was some slight signs of water damage which i've cleaned up.Measuring between the battery terminals gives me a resistance of ~120 ohms so that explains the battery drain.I'm unsure how to approach fault finding now, if it was a direct short i'd try getting some current through it and see what heats but it'll take a while to heat as it is!Any suggestions?

author: Psi
author_rank: Super Contributor
timestamp: January 02, 2024, 12:03:54 pm
content: Check with your phone camera on the IR output end to see if its constantly sending some IR data indicating that it thinks a button is being held down.Ya can't prove a negative but its worth checking (some phone cams show IR better than others, maybe check your phone with another IR remote to see)

author: Haenk
author_rank: Super Contributor
timestamp: January 02, 2024, 12:53:19 pm
content: Googling reveals that battery eating is a known problem on these.

author: Chet T16
author_rank: Frequent Contributor
timestamp: January 02, 2024, 08:58:12 pm
content: It's a known issue that they'll run down in about 2 weeks but this is within a day. And another remote I have doesn't have the same resistance between the terminals

author: BrokenYugo
author_rank: Super Contributor
timestamp: January 03, 2024, 04:16:45 pm
content: There's generally almost nothing in these but the button array and a blob chip, maybe a decoupling capacitor, and a ceramic resonator with loading caps for the clock generator. If cleaning doesn't fix it and the decoupling capacitor across the power supply hasn't gone leaky there isn't much more you can do.

author: Chet T16
author_rank: Frequent Contributor
timestamp: January 04, 2024, 06:16:22 pm
content: Theres actually no blobs in here, theres an MSP430 and OZMO2000 radio IC amongst others

author: floobydust
author_rank: Super Contributor
timestamp: January 04, 2024, 07:36:54 pm
content: Post pics of the board.I had a Sony remote the 100uF electrolytic cap on the main rail was installed backwards, it didn't pop at -3V but did kill batteries.You might have a shorted MLCC or IR driver etc. look around for the low resistance.