hybridfree/eevblog-posts huggingface dataset:
RIGOL  Phoenix  oscilloscope  DEMO  20GSa/s   4G BW - Page 1
Forum section: electronics / testgear

author: Wade2019
author_rank: Contributor
timestamp: August 16, 2021, 03:44:16 pm
content: Hello everyoneI accidentally obtained a Phoenix oscilloscope DEMO prototype. Unfortunately, the firmware of the machine is DS7000, so the performance is limited to 10GSa/s 500M BW. I don’t know if anyone can lift the limitation.

author: exe
author_rank: Unknown
timestamp: August 16, 2021, 05:38:57 pm
content: Ask rigol for firmware?

author: tv84
author_rank: Super Contributor
timestamp: August 16, 2021, 06:38:13 pm
content: Can you accidentally make a NAND dump? And show us the Options menu.

author: 2N3055
author_rank: Super Contributor
timestamp: August 16, 2021, 06:53:19 pm
content: Quote from: tv84 on August 16, 2021, 06:38:13 pmHahahahaha... LOL..

author: rsjsouza
author_rank: Super Contributor
timestamp: August 16, 2021, 06:59:48 pm
content: Quite interesting! This seems to have fallen from a van... That or your dumpster is a pot of gold as Dave's...

author: Bud
author_rank: Super Contributor
timestamp: August 16, 2021, 07:05:41 pm
content: No, a local bar customer left it on the counter, just like those iPhone prototypes.
A look inside TH2832 (Tonghui LCR) - Page 1
Forum section: electronics / testgear

author: luudee
author_rank: Frequent Contributor
timestamp: September 13, 2020, 10:16:36 am
content: I just got it and had to peek inside ...Enjoy the pictures, lolluudee

author: luudee
author_rank: Frequent Contributor
timestamp: September 13, 2020, 10:21:33 am
content: More pictures ...

author: luudee
author_rank: Frequent Contributor
timestamp: September 13, 2020, 10:24:34 am
content: More pictures ...

author: luudee
author_rank: Frequent Contributor
timestamp: September 13, 2020, 10:25:56 am
content: More pictures ...

author: luudee
author_rank: Frequent Contributor
timestamp: September 13, 2020, 10:27:34 am
content: More pictures ...Last One !

author: coromonadalix
author_rank: Super Contributor
timestamp: September 13, 2020, 02:31:50 pm
content: Seems pretty well made, the buzzer as big as the fan loll200khzthks for the pics

author: BravoV
author_rank: Super Contributor
timestamp: September 13, 2020, 02:35:16 pm
content: Thanks you for sharing, very nice.

author: luudee
author_rank: Frequent Contributor
timestamp: September 13, 2020, 04:06:55 pm
content: Quote from: coromonadalix on September 13, 2020, 02:31:50 pmYeah, I love the buzzer on that unit. I can actually hear it ! Best one out of all the equipment I have, lolluudee

author: Vgkid
author_rank: Super Contributor
timestamp: September 14, 2020, 08:35:47 am
content: Thanks for the teardown. It seems like Tonghui has always made pretty good equipment. Too bad they are not well known.

author: luudee
author_rank: Frequent Contributor
timestamp: September 14, 2020, 09:11:36 am
content: I forgot to show the accessories that came with the unit. I was positively surprised ...

author: luudee
author_rank: Frequent Contributor
timestamp: September 14, 2020, 09:15:05 am
content: By the way, my biggest worry about the unit is the fact that I can not access the Tonghui web site. It loads very, very slow, but I can never get to the TH2832 product page. So no access to firmware updates and whatever other software that might be available.It would be great if there would b e some sort of PC software, as the unit can create some large tables for the devices under test/evaluation ...Cheers,luudee

author: coromonadalix
author_rank: Super Contributor
timestamp: September 14, 2020, 10:42:43 am
content: Just checked just an user manual no FWKinda slow but accessible ?not sure if this lcr as no rebranded models ?

author: mawyatt
author_rank: Super Contributor
timestamp: August 15, 2021, 09:05:29 pm
content: Know this is an old thread.Any updates on how well the TH2832 LCR meter performs? Any reports on accuracy and drift?Best,

author: luudee
author_rank: Frequent Contributor
timestamp: August 16, 2021, 05:59:41 am
content: Even though I have been using it, I have not really paying too much attention to accuracy.It does need 15 minutes to "warm up". Not sure why, but that's what the manufacturer recommends.It seems to work quite well and readings are consistent. I don't have any other (highly accurate)equipment to compare against.Cheers,rudi
Tektronix MDO3034: no AC coupling with 50R termination? - Page 1
Forum section: electronics / testgear

author: tron9000
author_rank: Frequent Contributor
timestamp: August 17, 2021, 02:12:42 pm
content: Got an issue and just wanted to make sure I've not changed a setting somewhere.I have a 1:1 probe connected to a power supply rail to do some ripple tests and when I put the input to 50R termination, the AC coupling option greys out.Any ideas why? I got an older scope that can do it, so why can't this one?Cheers

author: thinkfat
author_rank: Unknown
timestamp: August 17, 2021, 03:11:48 pm
content: I'm just guessing, but the 50 Ohm termination is likely meant to be "real" over the full bandwidth of the 'scope and a capacitive component would add something "imaginary". Hence, no AC coupling.

author: tggzzz
author_rank: Super Contributor
timestamp: August 17, 2021, 03:15:30 pm
content: Quote from: tron9000 on August 17, 2021, 02:12:42 pmWhat's the benefit of using a 50ohm termination in that case? What's the cable length, lowest and highest frequency of interest?Be aware of the highest voltage allowed across the 50ohm, and which "side" of an AC coupling capacitor it is.

author: PartialDischarge
author_rank: Super Contributor
timestamp: August 17, 2021, 03:27:46 pm
content: In the TDS600/700 there was warning to reming you that the LF cutoff is very high in that case (around 200kHz). Maybe it was SW disabled in the MDO series

author: TimFox
author_rank: Super Contributor
timestamp: August 17, 2021, 03:47:34 pm
content: The 50 ohm termination resistor has a finite power rating, probably no more than 2 W. If AC coupling were allowed, you could easily have excess DC power dissipation in it.

author: med6753
author_rank: Super Contributor
timestamp: August 17, 2021, 04:22:50 pm
content: Quote from: tron9000 on August 17, 2021, 02:12:42 pmWhat scope is it that allows AC coupling with 50R termination? I have 2 scopes here (Tek 485 and Tek 2465) and a 7A24 plug-in for Tek 7000 series and all of them are DC coupled only.

author: MarkL
author_rank: Unknown
timestamp: August 17, 2021, 05:08:24 pm
content: Like the TDS600/700, the TDS3000 series can also do AC coupled with 50R termination. It displays a warning that the lower BW cutoff is 100kHz.If you want 50R termination, the DC level already has to be fairly low (5V RMS max). You could try bringing the trace on-screen by using the offset. Offset ranges are +/-0.5V, +/-1.0V, and +/-5V, depending on the V/div setting.Or just use an external thru terminator with sufficient power rating.

author: nctnico
author_rank: Super Contributor
timestamp: August 17, 2021, 05:51:08 pm
content: Another option is to use an external DC block. These are common to use on spectrum analysers; the higher end ones really don't like DC at their inputs.

author: tggzzz
author_rank: Super Contributor
timestamp: August 17, 2021, 06:26:09 pm
content: Quote from: med6753 on August 17, 2021, 04:22:50 pmTek 485: look at C101, 2.2µF, diagram 1 top left. C101 is between the BNC socket and the 50ohm attenuator.
Philips PM5786B 125MHz pulse generator teardown - Page 1
Forum section: electronics / testgear

author: picburner
author_rank: Frequent Contributor
timestamp: August 13, 2021, 02:59:25 pm
content: I bought this Philips pulse generator and, since I have to do some maintenance, I take the opportunity to take some shots during the teardown.The PM5786B (1Hz-125MHz 2nS-0.1S risetime) is a completely manual instrument, it doesn't include any remote control.The only maintenance works concern the replacement of a potentiometer with the broken shaft and the replacement of some electrolytic capacitors which have decreased their capacity and increased their internal resistance due to age.The first pic shows the front view of the instrument.The second pic shows the internal top view of the instrument.The third pic shows the power supply board (Unit 1), below is the transformer protected by its shield.

author: picburner
author_rank: Frequent Contributor
timestamp: August 13, 2021, 03:01:47 pm
content: Fourth and fifth pics: Transition time board (Unit 3).Sixth and seventh pics: Timing board (Unit 2).

author: picburner
author_rank: Frequent Contributor
timestamp: August 13, 2021, 03:03:46 pm
content: Eight and ninth pics: Burst control board (Unit 7).Tenth and eleventh pics: Front panel frame and board (Unit 6).Twelfth and thirteenth pics: Output amplifier board, Unit 4 & Attenuator board (Unit 5).

author: Scratch.HTF
author_rank: Regular Contributor
timestamp: August 16, 2021, 12:31:51 am
content: According to the service manual, the only custom IC in this unit is an analog multiplier and the ICs with a "100" prefix in the photos are off the shelf 100K ECL parts.

author: picburner
author_rank: Frequent Contributor
timestamp: August 16, 2021, 05:38:00 am
content: QuoteSharp observation. The IC in question is IC309 signed OQ0012 (I hope it lasts a long time).You can see it in the fourth pic on the right about in the middle.
HP8920B Agilent - Page 1
Forum section: electronics / testgear

author: Ricardo G
author_rank: Newbie
timestamp: August 15, 2021, 05:01:37 am
content: Hello, I need help with the HP8920B communication monitor, when I run the rf test on the receiver module, I have the message "Receiver Assembly (low)" in the 100MHz 614.3MHz IF and 500MHz 114.3MHz IF tests. I've already disconnected all the cables and boards and cleaned everything up, but the glitch remains. this failure decreases when the HP8920B is on for more than 3 hours, but it does not disappear. sorry for my bad english.

author: bob91343
author_rank: Super Contributor
timestamp: August 16, 2021, 12:53:17 am
content: I would consult a service manual, if you can find one.

author: Ricardo G
author_rank: Newbie
timestamp: August 16, 2021, 12:59:57 am
content: Dear Bob, i have the service manual, but I don't have enough knowledge to analyze and find the defect. I need help from someone who has advanced knowledge of this equipment. any help will be appreciated.Regards

author: bob91343
author_rank: Super Contributor
timestamp: August 16, 2021, 04:59:26 am
content: In that regard, I am not the guy. However, perhaps the symptom is mentioned in the service manual. It would pay to at least look for it.It pains me to own something I can't maintain. I do have to face reality and realize I can't fix all the stuff I have but at least I try to dig a little.I am totally unfamiliar with that unit. Parhaps you could post on groups.io or whatever it's called for the Agilent aficionados. Wait - let me look.Try this: HP-Agilent-Keysight-equipment@groups.ioor this:https://groups.io/g/HP-Agilent-Keysight-equipment/topics
Tonghui and GW Instek LCR Meters - Page 1
Forum section: electronics / testgear

author: mawyatt
author_rank: Super Contributor
timestamp: August 15, 2021, 10:31:20 pm
content: Any experiences with the Tonghui TH2830, 31, 32 and the Instek LCR 6020, 6100, 6200 LCR bench top meters, or other bench top precision type LCR meters?Best,
Retro test gear look bluetooth speakers  - Page 1
Forum section: electronics / testgear

author: fanOfeeDIY
author_rank: Unknown
timestamp: August 16, 2021, 01:59:44 pm
content: Just found that Kikusui is selling Bluetooth Speakers imitating their old models of test gears.Never had that idea, maybe fun if other brands do the same?https://www.kikusui.co.jp/addition/bsp/index?fbclid=IwAR0jrinEg3YpRxYWoo3KrMZNM-emPKXsiHbYTujl5CA1Bz1e9V5-Ox1aEAM

author: TimFox
author_rank: Super Contributor
timestamp: August 16, 2021, 03:25:24 pm
content: The BSP10 (upper left) would be cool with a live display.

author: justme1968
author_rank: Contributor
timestamp: August 16, 2021, 05:58:04 pm
content: just read the linked pdf documents on their site.the bsp-10 seems to have a raspberry pi-3 inside and the display is a touch screen with a live display.unfortunately all models are out of stock on amazon.co.jp. i would have ordered all three. they look great.

author: TimFox
author_rank: Super Contributor
timestamp: August 16, 2021, 08:52:35 pm
content: The link above was to a Japanese language pdf.

author: justme1968
author_rank: Contributor
timestamp: August 16, 2021, 08:54:32 pm
content: i found the english versions here:https://manual.kikusui.co.jp/B/BSP/index.html

author: Runco990
author_rank: Frequent Contributor
timestamp: August 16, 2021, 11:24:14 pm
content: I wonder if this could be a group buy thing.... can't find any place TO buy it! That is ultra cool!
UNI-T BW specs - Page 1
Forum section: electronics / testgear

author: StrikerRocket
author_rank: Newbie
timestamp: August 14, 2021, 05:17:03 pm
content: https://instruments.uni-trend.com/list_77/948.htmlI saw this while randomly browsing the internet, and wonder what is the meaning of the BW spec on the page: 25 to 150Mhz...Does that mean that you cannont measure anything below 25 Mhz? That looks totally weird and, well, pointless to me...I already own a cool Siglent SDS1202X-E by the way.Thanks for any ideas on this strange spec...

author: ataradov
author_rank: Super Contributor
timestamp: August 14, 2021, 05:56:13 pm
content: EDIT: Actually no, you can see in the model lists that models actually start at 25 MHz total bandwidth. That seems like the most pointless scope ever. I guess it is there to set some base price, so that other prices don't seem like a big deal. A typical marketing trick. Except they want you to get a quote to see the price, which makes even less sense.They have a configurable bandwidth limiter (all scopes have). A typical limit is 20 MHz, but 25 MHz works too, I guess.Of course you can probe any signals you like. Enabling the bandwidth limiter just eliminates high frequency noise when probing slow signals.

author: tautech
author_rank: Super Contributor
timestamp: August 14, 2021, 08:28:52 pm
content: Quote from: StrikerRocket on August 14, 2021, 05:17:03 pmWelcome to the forum.The 25 MHz refers to the UTD2025CL model and 150 MHz the UTD2152CL model.
Probem with PyVISA and a USB device (Siglent) - Page 1
Forum section: electronics / testgear

author: piranha32
author_rank: Unknown
timestamp: August 14, 2021, 05:44:33 am
content: Hello,I would like to ask if anyone has experience with using PyVISA with USB devices, and can help me debug this problem.I try to connect to Siglent's SPD 3303C power supply, the package can see the instrument, can open it as a TMC device, but most of the times reading from it fails on timeout. Sending commands not returning any output also works only from time to time (write() fail silently, unlike commands reading back).I can control the power supply using Siglent's Windows application, so the USB interface works. PyVISA has no problems connecting to RTB2004 in TMC mode, so this part also works. The firmware is upgraded to the latest version available on Siglent's web site (1.02.01.01.03R6). TImeout is set to ~2s, so there should be enough time to deceive the data.Initially I planned to get much smaller power supply, but decided to buy SPD3303C only because it can be controlled using VISA interface, so this is extremely frustrating.Attached images show screenshots of a successful execution of "*IDN?" query (after 25 failures), and a failure on the next run.

author: tautech
author_rank: Super Contributor
timestamp: August 14, 2021, 05:58:49 am
content: There may be some guidance here:https://siglentna.com/operating-tip/spd-programming-tips/

author: piranha32
author_rank: Unknown
timestamp: August 14, 2021, 06:12:03 am
content: Thanks!This helped. Apparently the problem is with SPD3303C requiring a delay between operations. Even issuing a read() directly after sending "*IDN?" leads to a timeout. Inserting 0.1 second delay is sufficient to avoid it.

author: piranha32
author_rank: Unknown
timestamp: August 14, 2021, 06:29:52 am
content: A quick update for those looking for help in the future:Siglent in the linked post says thatquery()will not work because it does not wait between sending the command and reading results. Current implementation ofquery()acceptsdelayargument, addressing this issue.The following command works fine:print(inst.query("*IDN?", delay=0.1))The same effect can be achieved by settingquery_delayproperty (no need to add delay to each query):inst.query_delay = 0.1print(inst.query("*IDN?"))Delay also has to be added after each command. If another command is sent too quickly, it will cancel execution of the preceding one.This code doesnotwork:inst.write("CH1:VOLTage 11.03") # this command will not be executedprint(inst.query("CH1:VOLTage?"))After adding a delay after write, the commands work as expected:inst.write("CH1:VOLTage 11.03")time.sleep(0.1)print(inst.query("CH1:VOLTage?"))
Hey, Multimeter! - Page 1
Forum section: electronics / testgear

author: bdunham7
author_rank: Super Contributor
timestamp: August 14, 2021, 02:01:23 pm
content: https://www.banggood.com/ANENG-Q60S-Q60-Digital-Multimeter-AI-Speech-Recognition-Transistor-Tester-6000-Counts-True-RMS-Auto-Electrical-Capacitance-Meter-p-1882459.html?cur_warehouse=CN&utm_source=emarsys&utm_medium=Mail_weekend143_steam&utm_campaign=newsletteremarsys&utm_content=leander&sc_src=email_4934991&sc_eh=bc0ba128dc59bed11&sc_llid=648992&sc_lid=217249905&sc_uid=xEqlk4nHz6&ID=6311971"Iiqua. Quis ipsum suspendise ultrices gravida. Risus commodo viverra maece-nas accumsan lacus vel facilisis.""Zero line fire detection".

author: highpower
author_rank: Regular Contributor
timestamp: August 14, 2021, 03:53:53 pm
content: I have a meter that is the inverse of that one. I don't talk to it...ittalks tome!

author: Gyro
author_rank: Super Contributor
timestamp: August 14, 2021, 04:14:52 pm
content: "Hey, I'm over here!".....https://www.eevblog.com/forum/testgear/hey-multimeter/(Sorry, it had to be done)
Non Destructive 3D Visualisation of COIL smallest problems to replicate as is ? - Page 1
Forum section: electronics / testgear

author: jackbruce
author_rank: Newbie
timestamp: August 13, 2021, 11:41:45 pm
content: I have a locked coil small with lots of problems should be replicated as it is. Exactly as the faults and problems, smallest detail must be known. Who can report and reveal with non destructive 3d analysis ?
Pouch for a Fluke 1507 - Page 1
Forum section: electronics / testgear

author: Khaveer
author_rank: Contributor
timestamp: August 12, 2021, 07:58:43 am
content: I'm looking for a pouch for my Fluke 1507. Apparently the recommended one is C25, but I really don't like the fact that it doesn't open all the way. I'd rather get something like the C35 but according to Fluke it's not compatible, however the dimensions are similar. Is there anyone who has the 1507/1503 and C35 and could verify if it fits? Some detailed photos of both pouches would also be appreciated.I'm also open to suggestions for other pouches since those cost more than I paid for the damn meter itself.

author: Fungus
author_rank: Super Contributor
timestamp: August 13, 2021, 02:16:39 am
content: Try this:https://www.aliexpress.com/wholesale?SearchText=multimeter+caseEdit: I keep my Fluke 27 in one ofthese. I prefer it to the "genuine" Fluke case because it has a separate compartment for the accessories.
A Siglent SDM3045X DMM bug? - Page 1
Forum section: electronics / testgear

author: Amaruk
author_rank: Contributor
timestamp: August 12, 2021, 08:07:35 pm
content: I love my new Siglent SDM3045X DMM! But I just noticed something strange on it. I know that over four years ago there were reports of this model having problems measuring the DC offset of an RF signal at 1kHz. I thought newer SW and HW versions had made this problem go away a long time ago. In a way that is true. The difference between then and now is that newer SW versions for this model have an (undocumented) DC filter function that will solve the problem but it is turned off by default.But I happened to discover that if the DC filter is off you can also get the correct reading if you change the DC offset up and back down while the RF signal is still on… very strange!Below is a video I shot that shows the problem and how you can get around it by adjusting the offset up and back down or turning the filter on.What do you think is going on in the DMM here? Anyone else have this issue?Link to my video:https://youtu.be/g6it3cXnVq0Here is a link to the initial report by TRX Lab from early 2017 about this exact issue (it starts around the 58 minute mark):https://youtu.be/K09BLgyk9Hg?t=3492For those interested, here is a link to a 2004 white paper from Fluke that I found that discusses the difficulties of of AC+DC measurements:https://us.flukecal.com/literature/articles-and-education/electrical-calibration/white-paper/making-accurate-dc-voltage-measUpdate: I heard from Siglent that the filter I show in the video must enabled for these measurements (not available on early SW versions). Thus, the hysteresis effect shown in my video by increasing and lowering the offset is more of a curiosity as the intended use is to have the filter enabled. For the price of this DMM we should not complain. I am just curious if more expensive bench DMM's also have a filter that the user must enable manually in situations like this. Does anyone know?
Labspire - Remote Test & Measurement Platform - Page 1
Forum section: electronics / testgear

author: labspire
author_rank: Newbie
timestamp: August 10, 2021, 09:45:04 pm
content: Hello, EEVBlog! My team has been working on a project called Labspire, a cloud platform for remote (as in, fully remote) electrical test & measurement automation. We know that there’s plenty of T&M enthusiasts here, so we would love to have the community try out our beta release and give us feedback!Some background on our project:One thing we’ve observed over the past year while working remotely is how outdated electronics tests and measurements are being conducted today. Many people still rely on expensive vendor software like LabVIEW to conduct their experiments, and to gain remote access, they have to set up dedicated VPN or remote desktop connections that are often slow and overkill. While there are other projects that use Python and other higher-level languages to address this, we’ve found that many of them require a unique combination of both hardware and software expertise to get started.That is why we created Labspire, a consolidated web platform that provides both a Jupyter web environment and a remote control API that will allow you to talk to your lab equipment through the web. We emphasized ease of setup and usage so that it takes minimal knowledge for a user to get up and running with a remote lab station.Our setup works like this: you connect a Raspberry Pi to your lab instruments, then using our custom-built image, you can connect to our cloud platform and interface with it through Python inside our Jupyter framework. Work with your oscilloscope, function generator, or any VISA-compatible instruments from the comforts of your own home!What you could test out right now:We have some physical demos (oscilloscopes, function generators, etc.) available for you to interface with, just follow the video guides or our Wiki for more information.Alternatively, if you have your own equipment and a Raspberry Pi sitting at home, you can install our custom image and connect them to our cloud platform.Check out our YouTube video for a closer look:https://youtu.be/Vo55EzmQtggOther Links:Our landing page:www.labspire.comLabspire forums:https://labspire.boards.net/Wiki documentation:https://wiki.labspire.com/
Tektronix TDS5054-NV-AV - 5050 Probe compensation not working (no waveform) - Page 1
Forum section: electronics / testgear

author: newtekuser
author_rank: Frequent Contributor
timestamp: August 11, 2021, 02:53:20 pm
content: Hi All,This is my first scope I bought on ebay auction for cheap, it was sold as working but I don't think it is. After receiving my p5050 probe, I turned on the scope, let it warm up for 20 mins then hooked up the probe to the terminals used for compensation and channel 1, hit the AUTOSET button and waited for a waveform to show up on the LCD.The only thing I get is noise regardless if I adjust the small screw on the probe itself, there's no difference in the waveform regardless of the direction I turn the screw.To troubleshoot, I hooked up my trusty multimeter to the compensation terminals on the front and only read 0.49v instead of the ~1v that is written on it. I am assuming the acquisition board may be faulty? (I'm assuming again that this terminal is coming from the acquisition board).I understand these scopes are sold as scrap and this was a long shot anyway as this is the second scope TDS5054 I'm returning (the first one made loud screeching noises upon start so I returned it). I know, I'm a sucker for tek scopes as I see them at work all the time (I am a SW guy by trade and training, but work for a major semiconductor company and walk by HW labs pretty frequently)What do you think about the probe compensation issue, am I missing anything critical here, or maybe the 0.49v signal is acceptable (though I doubt it) and I have a faulty probe?Also, all scope diagnostics pass, including SPC and scope doesn't make any funny noises except for the clicks from the acquisition board when adjusting settings.I hooked up the probe to a 9v battery and I do see a signal but I have to set the scale to lowest mV setting to see details.

author: tautech
author_rank: Super Contributor
timestamp: August 11, 2021, 11:11:33 pm
content: Welcome to the forum.Dud probe IMO and as a sanity check you can just use a piece of wire for a channel connection to the probe compensation output.

author: newtekuser
author_rank: Frequent Contributor
timestamp: August 11, 2021, 11:39:53 pm
content: Thanks tautech!I did run a wire from the CH1 to the compensation output and I do see a square wave. I suppose a bad probe then.

author: tautech
author_rank: Super Contributor
timestamp: August 11, 2021, 11:43:17 pm
content: Quote from: newtekuser on August 11, 2021, 11:39:53 pmOK cool so for you as a scope novice just get some cheap probes from eBay for now until you need start chasing any HF stuff.

author: newtekuser
author_rank: Frequent Contributor
timestamp: August 12, 2021, 12:19:35 am
content: That's really good to knowmuch appreciated
BM235 won't switch off - steady 1mA drain - Page 1
Forum section: electronics / testgear

author: wjsmarine4342
author_rank: Newbie
timestamp: August 11, 2021, 05:00:04 am
content: Hi All,I have two subject meters both working well but lengthy periods of non use too. #2 meter was difficult to start (hit and miss) but a fresh set of cells fixed it.8 weeks later same problem and cells were flat (.9v) whereas #1 still going strong. I tested #2 with an external 3v supply and measured 5mA running dropping to 1mA with switch off compared to 2mA and 0mA for #1.Both instruments don't leave the workshop and are treated with respect. Any ideas what to check next?Cheers,Bill

author: Fungus
author_rank: Super Contributor
timestamp: August 11, 2021, 03:09:58 pm
content: Off should be off.Take it apart and look for foreign bodies in the selector switch.
Tektronix 2236 CRT filter - Page 1
Forum section: electronics / testgear

author: jonpaul
author_rank: Super Contributor
timestamp: August 08, 2021, 06:08:49 pm
content: Bonjour a tous,Recovered a 2236 from the Laundry room, sitting there for 20 years.Had slight water stains and corrosion on the back which was on the floor during a leak.Cleaned up fine and is in CAL for scope and DVM, had CAL sticker from 1989.But the blue CRT filter has several smudges and abrasions on the plastic,.The filter is an odd outline, to fit the swing up bezel hinge.Part is 337-2775-00If anyone has spares I am very interested.Also, need TORX T-15 screws for back cover, 6-32 thread, length 5/8"MANY THANKS!Jon

author: richmit
author_rank: Contributor
timestamp: August 10, 2021, 07:06:56 pm
content: Quote from: jonpaul on August 08, 2021, 06:08:49 pmIf it is a plexiglass filter like the one on my 2235, then you might be able to polish out the scratches out with a little bit of work. If the scratches are fine, then Novus 2 plastic polish will do the trick. If you have really deep scratches then you can start with some 2500-3000 grit wet sand paper.
Tektronix TLA7012, what's it worth? - Page 1
Forum section: electronics / testgear

author: Inari
author_rank: Contributor
timestamp: July 27, 2021, 09:31:44 am
content: What is this worth?If it seems to work but needs upgrades?Here in europe, they seems to be for sale couple of hundreds Euro.For example,https://www.osta.ee/en/tektronix-tla7012-logic-analyzer-vajab-uuendust-tarkvarale-160049504.htmlbut as I have seen then the prices of the hardware sold are usually below 500. The cables alone should be worth more if I am correct?

author: nctnico
author_rank: Super Contributor
timestamp: July 27, 2021, 09:41:05 am
content: The cables aren't worth much either. These are great logic analysers but nobody uses a logic analyser nowadays so you can pick them up for peanuts. I'd like a TLA7012 myself but realistically my TLA715 doesn't see enough use to justify the costs. If you can get it for a couple of hundred euro and need a logic analyser then it is a great deal.Upon closer inspection it looks like the probes that come with it are not for the module fitted in the logic analyser so basically it comes without probes.

author: Inari
author_rank: Contributor
timestamp: July 27, 2021, 10:00:22 am
content: Thanks. Nor do I have any use or very little for it, I mean more than a collectible object - a disease problem that many are likely to suffer from

author: Inari
author_rank: Contributor
timestamp: August 05, 2021, 11:09:38 am
content: After contacting the seller, it turned out that he had more measuring instruments, so I gave up the option of buying this analyzer and will probably focus a Tek TDS6154C - 15GHz scope.Sadly that this seems broken and previous owner labelled this like "expensive to repair" - i quess input or ADC...but anyway, may be good to own as an exhibit.This TLA7012 analyzer ended up little over 1k€.

author: MindBender
author_rank: Regular Contributor
timestamp: August 10, 2021, 07:11:34 pm
content: Quote from: nctnico on July 27, 2021, 09:41:05 amYou've got a point, but I don't entirely agree with you: If you've validating DDR3 timing in your design, you will need a good logic analyzer, preferably with the ability to monitor analog wave-forms on selected channels too. But gone are the days of debugging software by having a logic analyzer monitor the CPU's address/data-bus, disassembling captured data and inlining your source into it. (with all the complications that pipelines and cache bring along).I own a very complete TLA7012, with a number of digital modules, an analog oscilloscope module, the PCI analyzer module and the Pattern Generator module with both differential and single-ended probes. On a trolley, of course. But you're right; It's not worth much. If you need one, there's no other tool that can do the job, but that doesn't happen very often, and the rest of the time it's standing in the way.I wish it supported more serial protocols: I2C, SPI, etc. But with cheap alternatives getting cheaper and better, it's of not much use. It does decode and even encode CSI, but even that is a dying protocol nowadays. It's a fun instrument to play with tough. For a couple of days.
Will many Keysight 34401A DMMs may come to the used market next year? - Page 1
Forum section: electronics / testgear

author: graybeard
author_rank: Frequent Contributor
timestamp: April 21, 2021, 10:13:40 pm
content: I just talked with Keysight and they told me that support for the discontinued Agilent/Keysight 34401A DMM will end on March 2022.The very large company I work for probably has thousands of 34410As and usually will surplus equipment that is no longer supported. My guess is that other companies may do the same.It is already common to find 34401As on the used market. Will there be many more next year when support ends?

author: Algoma
author_rank: Frequent Contributor
timestamp: April 21, 2021, 10:33:42 pm
content: Plenty of demand right now, its a challenge to find deals on anything useful and working on surplus market. Compare the specs vs cost, and its often a FAR better deal to buy new.Good resale market for businesses to sell off surplus and trade up right now.

author: bdunham7
author_rank: Super Contributor
timestamp: April 21, 2021, 10:39:21 pm
content: Quote from: graybeard on April 21, 2021, 10:13:40 pmGenerally I understand ditching unsupported equipment where support is part of the everyday requirements, but what support do these DMMs need? Calibration will still be available, repairs are seldom needed and they can be cycled out when they do break. Your company may be different, but I commonly see surplus stuff coming 'off the line' that is quite a bit more obsolete. I suspect most companies aren't going to throw their 34401As out on the loading dock the day Keysight stops 'supporting' them. If they do, I'll be happy to pick them up for a very small recycling fee.

author: bob91343
author_rank: Super Contributor
timestamp: April 21, 2021, 10:41:47 pm
content: Put me on that list, at least for two of them.

author: jjoonathan
author_rank: Frequent Contributor
timestamp: April 21, 2021, 10:56:19 pm
content: Keysight might not support them but the cheerful local calibration van will be happy to slap a sticker on there and print a cal certificate. For a nominal fee -- but less than you all want to buy 34401As for, in all likelihood

author: eurofox
author_rank: Unknown
timestamp: August 10, 2021, 12:15:20 pm
content: Numerous Agilent 34401a available here :https://www.surplustechmart.com/They are on ebay as well.I bought one
Soviet logic analyzers (Made in USSR) - Page 1
Forum section: electronics / testgear

author: Scratch.HTF
author_rank: Regular Contributor
timestamp: August 08, 2021, 01:55:20 am
content: I've come across Soviet oscilloscopes and certain other test equipment along with a Soviet clone of a Tektronix logic analyzer plugin, but do you know of any Soviet logic analyzers (made in USSR) which have a trace memory of at least 1000 samples?

author: khach
author_rank: Contributor
timestamp: August 08, 2021, 08:58:51 pm
content: What about Я4-110? That is a logic analyser plugin for С1-122 modular oscilloscope.

author: Bassman59
author_rank: Super Contributor
timestamp: August 08, 2021, 09:22:16 pm
content: In Soviet Russia, logic analyzes YOU!

author: khach
author_rank: Contributor
timestamp: August 08, 2021, 09:53:55 pm
content: Yes, 800 series. Some models descriptionhttps://zapadpribor.com/category/analizatory-potoka-dannykh/
HP ESA-L1500A Spectrum Analyzer Restoration - Page 1
Forum section: electronics / testgear

author: atkelar
author_rank: Contributor
timestamp: August 06, 2021, 11:17:03 pm
content: I thought this project might interest a few residents here. I recently found a used (and seemingly also abused) spectrum analyzer on ebay. Did my usual "tear down, clean fixup" routine with it... now, I only have to learn about half of the features it has, cause I'm pretty new to anything but DC and digital signals. Hopefully this new gadget will help me get a feeling for things a bit closer than just a scope alone. I did manage to use it for proper alignment of an FM signal so far. At least accoring to the service manual; would have loved to know what exactly I did there, but the frequency range was within the required tolerance after I finished.The project video is in my usual format, might not be everyones cup of tea, but at least it's slightly different from the run of the mill stuff:
LED Strips to Replace CFL Tubes in TDS3000 Series scopes - Page 1
Forum section: electronics / testgear

author: daveyk
author_rank: Frequent Contributor
timestamp: August 07, 2021, 05:33:46 pm
content: Does anyone have good experience with LED replacement of the CFL Tubes in a Tek TDS3000 series scope?I work on an instrument that uses the same display. It is commonplace for the instrument to be dropped and the tubes broken. The source of the replacement tubes has run dry for the most part, and an LED upgrade would so much nicer, maybe.Can anyone point me to a driver PCB and LED Strip that is appropriate for these displays? Without looking, the DFL tubes are about 6" long. They are dim-able in the instrument in use, but that capability could be eliminated if need be.There are probably numerous options, but I would prefer experience and not have to engineer a solution from scratch. At least point me towards parts that should work - lol.Thanks

author: daveyk
author_rank: Frequent Contributor
timestamp: August 07, 2021, 06:46:35 pm
content: On my own, I found this:https://store.lcdparts.net/UB35160LED3220X2MS610UB-for-65%E2%80%9D-Dual-Lamp-LCD-Screen_p_4548.htmlWith shipping, this is a $170 solution (and I did order one kit). For what I use it for, that is acceptable, but I would bet a lot cheaper solutions are around. I just have never used strips of LED lights and do not know how to order to match up with a driver PCB. Are the LEDs typically all in parallel or series, or a combination of both?I would like to find a roll of LED strips that can be cut and and wired to and then a driver PCB.

author: TheDefpom
author_rank: Frequent Contributor
timestamp: August 07, 2021, 07:41:48 pm
content: I picked up some LED strips with drivers (yet to be needed) from Aliexpress a couple of years ago, maybe have a browse around there.

author: nctnico
author_rank: Super Contributor
timestamp: August 07, 2021, 08:55:49 pm
content: Quote from: daveyk on August 07, 2021, 06:46:35 pmThese are horribly expensive!Buy something like this:https://www.ebay.com/itm/271944994132But be aware that you'll need to adjust the current sensing resistor if you are cutting LEDs from the strip AND determine how many LEDs are in series; you can't cut an arbitrary number of LEDs! I have used similar strips in (IIRC) two or three TFT screens and they work like a charm.

author: james_s
author_rank: Super Contributor
timestamp: August 07, 2021, 10:06:20 pm
content: About 8 years ago I replaced the backlight in a friend's Toshiba Libretto subnotebook with LED strips. I bought a generic retrofit kit, I think it was about $20 and I had to trim the length of the strips to size but overall it was fairly straightforward. It looked good and as far as I know it's still working.
Datron 4700 Calibrator Repair Series - Page 1
Forum section: electronics / testgear

author: TheDefpom
author_rank: Frequent Contributor
timestamp: April 23, 2021, 12:06:17 pm
content: I begin the repair of a Datron 4700 Multifunction Calibrator.

author: TheDefpom
author_rank: Frequent Contributor
timestamp: May 01, 2021, 11:11:46 am
content: Part 2:

author: TheDefpom
author_rank: Frequent Contributor
timestamp: May 06, 2021, 01:10:47 pm
content: Part 3

author: TheDefpom
author_rank: Frequent Contributor
timestamp: May 14, 2021, 11:28:52 pm
content: Part 4:

author: Grandchuck
author_rank: Super Contributor
timestamp: May 15, 2021, 12:59:26 pm
content: Great series ... thanks Scott!

author: TheDefpom
author_rank: Frequent Contributor
timestamp: August 06, 2021, 10:16:11 pm
content: Unexpected Part 5:
Sad tale of my SSA3032X and a warning - Page 1
Forum section: electronics / testgear

author: 7 of 9
author_rank: Newbie
timestamp: August 13, 2021, 07:15:44 pm
content: Hi All,A few weeks ago I bought an "As New" SSA3032X spectrum analyser, and it was as described, in mint condition and came with the reflection bridge and license, it was originally bought in August 2019 so still under warranty?Anyway I was very pleased with the unit, here are some things I maybe should not have done?I set the time & date. I then checked the Siglent website for any firmware updates, there was ,so I downloaded version 1.3.9.7 and installed itwhich was possibly another error ? and I also did a factory reset, another error?Well the outcome of this was that the two trial licenses for EMI & AMK (which had not been used) have now expiredand along with this all the measure functions have been greyed out so are unusable.I contacted Siglentna.com as I thought I had broken the SSA, the reply was:The MEAS functions are all tied to the Advanced Measurement Option, part number SSA3000X-AMK. You can see them listed here:https://siglentna.com/product/advanced-measurement-activation-license/The trials are provided for a time duration, whether or not they are used. The SSA3000X has approximately 40 hours of trial time for all of the trials. The timer runs when the instrument is plugged in.As I am just a hobbyist I can not afford or justify the cost of the licences.I would have liked to at least trial the EMI & AMK features. Is there a way I can get them back?Anyway beware if you buy a second hand SSA as I did.

author: tv84
author_rank: Super Contributor
timestamp: August 13, 2021, 07:23:52 pm
content: Unfortunately there are sadder stories in this forum. See pm.
Really Odd Meterman 37XR Problem - Page 1
Forum section: electronics / testgear

author: mdonald623
author_rank: Newbie
timestamp: December 20, 2013, 04:38:24 pm
content: Hello EEV blog forum, first time poster here, love the show!Okay so I recently came into possession of a "broken" Meterman 37XR. I turned it on and found that it beeps and displays "ERR" as if the probe is plugged in the wrong position. I started messing around with it thinking maybe something conductive got down in the 10 amp or mA terminal and suddenly it decided to work. I checked it out and everything works great, awesome, $150 multimeter for free I thought. So later that day I went to show it to a friend and of course the error was back full force. It turns out this error likes to come and go so I started to think I'd never fix it and it was just a goner.Well today I found something rather interesting. I took the back off the multimeter and I started probing around and I found nothing that really jumped out at me, though I really only know just enough to make speculations. However I found out entirely by accident that by breathing on the damn thing I could set off the error!! I probed the two terminals in between the mA range and blew on it and watched as the resistance dropped drastically! I really am in over my head here as I couldn't come up with a logical reason this would happen. Clearly this meter was designed to handle humid environments, so why can't mine?I would be entirely open to sending it to Dave for inspection/repair if he is interested.

author: PedroDaGr8
author_rank: Super Contributor
timestamp: December 20, 2013, 06:23:52 pm
content: Quote from: mdonald623 on December 20, 2013, 04:38:24 pmSounds like a cracked/dry/damaged/old solder joint. Heat from your breath causes the metal to swell filling the small cracks, dropping the resistance. I would take your trusty soldering iron and just remelt everything down there and see if that doesn't fix it. The other option is a cracked/damaged trace which you would have to probe all of the traces and then jumper the damaged trace with a wire. My guess is this will be easily fixed, just keep your eye open for cracked joints or joints that are dull and not shiny (this latter only applies to lead containing solder, lead free always looks dull)

author: mdonald623
author_rank: Newbie
timestamp: December 20, 2013, 06:50:30 pm
content: Alright I'll try that and report back later today, thanks.

author: tautech
author_rank: Super Contributor
timestamp: December 20, 2013, 07:35:38 pm
content: QuoteUse freeze spray and hot air gun to isolate problem area

author: nickshortie
author_rank: Newbie
timestamp: August 05, 2021, 07:07:44 pm
content: I know this thread is almost 8 years old but I just had the same issue with an 37XR-A and was able to figure out the problem and thought I'd share.The problem is the two Amp sockets which are split in half for plug detection. If the contacts are a little bent and touch each other the multimeter displays 'Err'cheers!
tektronix 2467b measurement issues - Page 1
Forum section: electronics / testgear

author: mj21
author_rank: Regular Contributor
timestamp: May 02, 2014, 09:41:25 am
content: hi all,recently i got a tek 2467b from ebay which i managed to fix. the scope is working ok and it passes all tests when doing the self test, but when i try pressing the measure button and try to get the frequency readout i get noisy or aperiodic signal error. does any one know what the problem might be?also how can you check the on time and power cycle?many thanks

author: Andy Watson
author_rank: Super Contributor
timestamp: May 02, 2014, 10:53:06 am
content: Press and hold both the delta V and delta T cursor buttons. Whilst these are held-in, press the Slope button to get to the "Diagnostic/test" screen. Use the trigger Mode buttons to scroll up or down the menus to find "Exer 05". Press the upper trigger Coupling button to display hours and power cycles.

author: BravoV
author_rank: Super Contributor
timestamp: May 02, 2014, 11:09:58 am
content: +1, and the scrren will look like this, example from 2465B.

author: mj21
author_rank: Regular Contributor
timestamp: May 02, 2014, 11:41:31 am
content: tnx. got hrs on 1045 and pwr on/off 359. is that good?

author: edavid
author_rank: Super Contributor
timestamp: May 03, 2014, 05:33:18 am
content: Quote from: mj21 on May 02, 2014, 11:41:31 amUnfortunately it's meaningless, since it can be reset easily.

author: EV
author_rank: Frequent Contributor
timestamp: May 03, 2014, 12:12:33 pm
content: Quote from: edavid on May 03, 2014, 05:33:18 amHow it is done?

author: Andy Watson
author_rank: Super Contributor
timestamp: May 03, 2014, 12:40:30 pm
content: Remove the covers, change a link to put the machine into "cal" mode and then follow the above procedure. The same menus occur but with the option to tweak the values.

author: EV
author_rank: Frequent Contributor
timestamp: May 03, 2014, 12:43:39 pm
content: OK, thanks!

author: Jelcke
author_rank: Contributor
timestamp: August 05, 2021, 05:25:29 pm
content: Hi mj21,Did you manage to fix the issue with "noisy or aperiodic signal error" when doing an auto setup or measurement?Thanks,Jelcke
Uni-T UT61D+ vs Uni-T UT61E+ - Page 1
Forum section: electronics / testgear

author: unknown_h
author_rank: Contributor
timestamp: August 05, 2021, 09:02:04 am
content: I am looking for a good first multi meter that will last me long in the future and I came across the Uni-T UT61D+ it seems to be very similar to Uni-T UT61E+ Dave reviewed without the gimmicky transistor tester and instead a temperature prob. Is the UT61D+ any good, I am struggling to understand the data sheet and differences between the two? [ Specified attachment is not available ]

author: Andrew_Debbie
author_rank: Frequent Contributor
timestamp: August 05, 2021, 09:21:35 am
content: The UT61E+ is a 22,000 count meter. The D+ is 6000 count. Most of the time that makes no difference at all.For example a 12V car battery might read 13.41V on the UT61D+ and 13.412V on the UT61E+.If you need the extra digit depends on what you are using the meter for.A fully charged LiIon battery would read as 4.200V on both meters.The same goes for the transistor checker vs. temperature. On E+ AC volts works all the way to 10KHz, which most of the time is not important.

author: Fungus
author_rank: Super Contributor
timestamp: August 05, 2021, 12:49:19 pm
content: The 61E is an order of magnitude more accurate.Is that important? Not really. Not unless you want to see tiny changes in voltage, like eg. battery discharging.It can also measure much higher resistance and capacitance, that might be more important.