hybridfree/eevblog-posts huggingface dataset:
Mouse wouldn't respond and move its cursor when it's supposed to be - Page 1
Forum section: electronics / repair

author: abdulbadii
author_rank: Frequent Contributor
timestamp: November 07, 2021, 01:30:19 pm
content: The wireless optical mouse has been working great until recently as I typed something then leaving it idle for several seconds, then as I was to move my mouse again it wouldn't respond and move its cursor when it's supposed to be moving. If I turned off the mouse, then back on, and it worked again. Then I began typing, and when I went to move my mouse again, the cursor again didn't move. I switched to a different USB port, checked by using very good battery, and tweaked the setting to no avail. It's on Linux, though googled it found that many the exact same trouble on other OSLuckily at such point it always does respond to click and scroll-wheel then immediately moving its cursor but it'd jump to a far distance randomly.Any idea what actually the incorrectness or weakness here ?

author: testpoint1
author_rank: Frequent Contributor
timestamp: November 07, 2021, 02:59:22 pm
content: if your home's wireless router (2.4GHz) is not close the mouse, and try another PC, if no help, you can consider the mouse had the problem.
Mouser EXPORT REVIEW - But all my orders go to a Mainland USA address - Page 1
Forum section: electronics / repair

author: ThermallyFrigid
author_rank: Frequent Contributor
timestamp: October 10, 2021, 03:26:28 am
content: Kinda of a repair question...since they are parts needed for a repair?Didn't see a specific place to ask.I've ordered from Mouser many times.First time this has happened.The orders ALWAYS go to my town which is in Florida.Is Mouser saying Florida is a foreign country now? (lol)Are they concerned I may be sending items out of the country? (I'm not, in fact, most of them probably come from China originally anyway)Did they just make a mistake?Sadly, now my order will be delayed until I clear this up.

author: PartialDischarge
author_rank: Super Contributor
timestamp: October 10, 2021, 04:00:09 am
content: Yes, probably they will ask you if you are going to sell those items abroad. Which they don’t want because the manufacturer doesn’t want to you to do so, because they may have other official channels out there

author: bdunham7
author_rank: Super Contributor
timestamp: October 10, 2021, 04:48:06 am
content: So...what parts are they exactly?

author: ThermallyFrigid
author_rank: Frequent Contributor
timestamp: October 11, 2021, 03:18:19 am
content: Quote from: MasterTech on October 10, 2021, 04:00:09 amOk, I have been buying a lot from them lately...so I guess that's a trigger.Thx
MOVED: (WTB ) I will buy a Rohde Schwarz NRV-Z1 probe - Page 1
Forum section: electronics / repair

author: Jarek
author_rank: Regular Contributor
timestamp: June 02, 2023, 11:02:17 pm
content: This topic has been moved toBuy/Sell/Wanted.https://www.eevblog.com/forum/index.php?topic=379559.0
MOVED: CORDLESS VACUUM POWER FAULT - Page 1
Forum section: electronics / repair

author: Adamitch3
author_rank: Newbie
timestamp: October 01, 2025, 12:13:03 am
content: This topic has been moved toProjects, Designs, and Technical Stuff.BEEN READ 500+ TIMES BUT NO ANSWERS ?!https://www.eevblog.com/forum/index.php?topic=411286.0
MOVED: Dremel 1100 repair didn't last - options for new Dremel-like tool? - Page 1
Forum section: electronics / repair

author: Halcyon
author_rank: Unknown
timestamp: July 01, 2025, 05:27:39 am
content: This topic has been moved toOther Equipment & Products.https://www.eevblog.com/forum/index.php?topic=464877.0
MOVED: Functions generator XR2206 and oscilloscope FNRSI DSO152 - Page 1
Forum section: electronics / repair

author: kbm
author_rank: Newbie
timestamp: May 09, 2024, 06:44:41 am
content: This topic has been moved toBeginners.This is question from Beginnerhttps://www.eevblog.com/forum/index.php?topic=427543.0
MOVED: Looking for a datasheet AD T9611 - Page 1
Forum section: electronics / repair

author: DanTheDuck
author_rank: Newbie
timestamp: May 06, 2020, 07:29:39 pm
content: This topic has been moved toProjects, Designs, and Technical Stuff.https://www.eevblog.com/forum/index.php?topic=240882.0
MOVED: Looking for the pinout of the Li-Ion backup battery in HP Gen10 servers - Page 1
Forum section: electronics / repair

author: RoGeorge
author_rank: Super Contributor
timestamp: May 07, 2024, 05:21:13 pm
content: This topic has been moved toProjects, Designs, and Technical Stuff.It started as a pinout request for a backup battery used in ProLiant HP servers, the info is nowere to be found, so it all turned into a HW+SW project about detecting the pinout + talking with a MAX17817 battery management chip over the SMBushttps://www.eevblog.com/forum/index.php?topic=426565.0
MOVED: Power supply board issues - need help to understand electric schema  - Page 1
Forum section: electronics / repair

author: vladc77
author_rank: Regular Contributor
timestamp: September 03, 2024, 10:04:20 am
content: This thread is similar to another I started a few days ago.Beginners.https://www.eevblog.com/forum/index.php?topic=438777.0
MOVED: Repair Horizon CT 7.1 Treadmill - Page 1
Forum section: electronics / repair

author: sairfan1
author_rank: Frequent Contributor
timestamp: January 21, 2020, 09:33:53 pm
content: This topic has been moved toBeginners.Did not get answer in Repair Forumhttps://www.eevblog.com/forum/index.php?topic=225830.0
MOVED: Tektronix TDS3000 (TDS3052B, TDS3034B) no boot, NVRAM OK, PSU OK - Page 1
Forum section: electronics / repair

author: benj38
author_rank: Frequent Contributor
timestamp: April 28, 2025, 06:11:58 pm
content: This topic has been moved to "Test Equipment" in order to generally discuss the boot process of these scopes
MOVED: Telescope Mount Bricked After Firmware Update - Page 1
Forum section: electronics / repair

author: drDuesentrieb
author_rank: Newbie
timestamp: January 04, 2024, 09:33:17 pm
content: Following magic's advice, the topic is moved toMicrocontrollers.https://www.eevblog.com/forum/index.php?topic=408015.0
MOVED: TPA3116 strange output wave form - Page 1
Forum section: electronics / repair

author: Michaelaudio
author_rank: Regular Contributor
timestamp: September 16, 2020, 01:00:34 pm
content: This topic has been moved toProjects, Designs, and Technical Stuff.https://www.eevblog.com/forum/index.php?topic=253666.0
MOVED: Unable to install Windows 2000 on Intel D845GVAD2 microATX desktop board - Page 1
Forum section: electronics / repair

author: Halcyon
author_rank: Unknown
timestamp: April 05, 2023, 04:17:04 am
content: This topic has been moved toComputers.https://www.eevblog.com/forum/index.php?topic=371867.0
Moving Option 004 from one HP Spectrum Analyser to another - Page 1
Forum section: electronics / repair

author: numbersix
author_rank: Newbie
timestamp: June 27, 2021, 09:52:35 pm
content: Hi folks,I've had an HP 8594E Spectrum Analyser for a while, but have only recently been able to use it because of a faulty PSU which needed to be repaired. Now I've had that sorted out I am starting to get to grips with it a bit and have found out to my surprise that it actually has the tracking generator option in it which makes it considerably more useful. The charity that I run (we restore a Cold War era nuclear bunker with computer/radio kit from the 60s-90s which we repair/maintain) was also recently given an HP 8591C Cable TV Analyser to use for spares (it has a good screen, PSU etc) which came with option 004, 101, 130 and a couple of others related to TV functions. Using other forum posts here I was able to move the option 130 board over to my 8594E and that's working nicely. I moved option 101 over as well.What I was wondering though is what's involved in moving the option 004 precision frequency reference option parts over from the 8591C to the 8594E. I can't find a lot from Google other than finding that option 004 was available as a retro-fit option from HP.Any help would be gratefully received.Regards,Gavin.

author: Miti
author_rank: Super Contributor
timestamp: June 27, 2021, 11:41:52 pm
content: Welcome to the forum!I did exactly that not too long ago. Just move the OCXO to the recipient instrument, then plug the connectors. When you power it up, you’ll get the “Oven cold” for 5 minutes and the option shows up in the list. It’s plug and play. You’ll loose the electronic adjustment, adjust it manually if needed.

author: numbersix
author_rank: Newbie
timestamp: June 28, 2021, 05:49:28 pm
content: Awesome, thank you. I've just moved it over and it seems to be working nicely. Undoing/doing up the last nut right next to the ribbon cable connector on the card reader was a bit of a pain because my 5.5mm nut driver wasn't slim enough, but loosening the card reader PCB just let me get around to it.I've been through and written down all my calibration data and the next job is to try and replace the battery without losing my cal data.Now if only I could find a GPIB/parallel interface board for it!

author: Miti
author_rank: Super Contributor
timestamp: June 28, 2021, 08:09:54 pm
content: If you wrote the numbers down, there’s nothing to worry about.

author: numbersix
author_rank: Newbie
timestamp: June 28, 2021, 08:29:07 pm
content: I did, I used the paper form in the manual and even typed it up into a spreadsheet to be sure I won't lose it.

author: Miti
author_rank: Super Contributor
timestamp: June 29, 2021, 02:37:49 am
content: If you have option 103 you may be interested in this post:https://www.eevblog.com/forum/testgear/hp8590e-series-option-103-driver/
MP3 player ghost battery - Page 1
Forum section: electronics / repair

author: PerranOak
author_rank: Frequent Contributor
timestamp: November 04, 2019, 06:22:35 pm
content: I have an old style MP3 player and am investigating it … well I was!I wanted to see what current it took so I removed the AA battery and connected the player's terminals to the PSU. However, it would not start.To cut a long story short, I tried "everything" including putting in a false battery in case, somehow (magic?), it can detect a battery, but nothing worked.When I put a battery in - in the ordinary way - it works perfectly.Whatcouldbe going on?Cheers.

author: shakalnokturn
author_rank: Super Contributor
timestamp: November 04, 2019, 10:37:54 pm
content: Some devices (Sony?) had a switch for battery type detection, primary or rechargeable.Doubtful, but wire resistance could be a problem with external power, try decoupling close to MP3 player.A couple of photos would help: Player and test setup.

author: NiHaoMike
author_rank: Super Contributor
timestamp: November 05, 2019, 01:25:31 pm
content: Probably too much inductance. Try adding a capacitor right at the battery terminals, 100uF or more.

author: PerranOak
author_rank: Frequent Contributor
timestamp: November 07, 2019, 02:20:36 pm
content: Cheers both.While investigating, I forgot to set the current limit on the PSU - now I've fried it totally. I must have shorted something or something.Thanks anyway.
MPPE hookup wire and soldering - Page 1
Forum section: electronics / repair

author: bob_mllr
author_rank: Newbie
timestamp: October 26, 2020, 06:27:16 am
content: Hi, Just wondering if anyone has used MPPE hookup wire (like Alpha EcoWire) for point to point wiring in valve radio repair, and how the insulation handles soldering? Compared to PVC say? Thanks.
MPPT - transistor has failed - Page 1
Forum section: electronics / repair

author: Artem
author_rank: Newbie
timestamp: October 17, 2024, 07:58:42 am
content: Greetings,The 040N04PT field effect transistor in MPPT solar change controller has failed. I checked some characteristics of the second one. There is no information about them on the internet. The only thing I found is a photo on the forum with the same transistor, but next to it is soldered NCE40H12. I bought 5 of NCE40H12 transistors on Aliexpress and I don't know if they will really fit. They are most likely a fake. When I checked them, 2 of the 5 still have a voltage drop between the drain and source when the transistor is open.Can you please tell me what can be used to replace the failed 040N04PT transistor?Is it true that 2 of the 5 transistors I bought are faulty?RegardsArtem

author: fzabkar
author_rank: Super Contributor
timestamp: October 17, 2024, 09:45:45 am
content: https://file2.dzsc.com/icpdf/20/10/28/1160107_111207025.pdf(NCE40H12)

author: Harry_22
author_rank: Frequent Contributor
timestamp: October 17, 2024, 10:13:13 am
content: Seems the data are close to BSZ040N04LShttps://www.infineon.com/dgdl/Infineon-BSZ040N04LS%20G-DataSheet-v02_00-EN.pdf?fileId=db3a3043163797a6011643b9e30f067bEquivalents are here:https://alltransistors.com/mosfet/crsearch.php?struct=&polarity=n&pd=60&uds=40&ugs=0&ugsth=0&ugsoff=0&id=100&tj=0&qg=38&fr=0&cd=700&rds=0.004&caps=to220&cf=onPSAli is not the best place to buy transistors, especially original ones.
MRF 486 - Page 1
Forum section: electronics / repair

author: Ct1jrz
author_rank: Contributor
timestamp: November 12, 2020, 11:17:21 am
content: HelloAnyone knows were I can find original transistors MRF 486?Thanks

author: bob91343
author_rank: Super Contributor
timestamp: November 12, 2020, 10:12:20 pm
content: You want the part, or the data sheet?

author: Ct1jrz
author_rank: Contributor
timestamp: November 13, 2020, 08:29:30 am
content: HelloThank you for the question.I´m looking for transistors.You are right the, I didn´t ask correctly.I changed the question.Thank you

author: bob91343
author_rank: Super Contributor
timestamp: November 13, 2020, 07:11:23 pm
content: I don't know that part. I am familiar with the MRF485; is this also a medium power rf transistor?
Msi 1080 ti duke 11gb- need help identifying component. - Page 1
Forum section: electronics / repair

author: Eg3300401
author_rank: Contributor
timestamp: November 03, 2022, 04:31:17 am
content: Found a fried component on board It has ELMCF on it. And I couldn't find anything on it. Can anyone help identifying component or something similar?

author: fzabkar
author_rank: Super Contributor
timestamp: November 03, 2022, 05:25:20 am
content: Not confident of this ...https://www.ebay.com/itm/275293616953https://www.aliexpress.us/item/3256802526272233.htmlhttp://www.gstekic.com/pdf/GS7612.pdfhttp://www.gstekic.com/product_list_en.php?product_major_id=31https://bbs.pigoo.com/data/attachment/forum/202210/01/161044lrzpvs6pndpvd9vv.jpg(ELMCC)https://www.google.com/search?q=elm+%22sot23-5%22&tbs=isz:m,itp:photo&tbm=ischEdit:These guys have worked it all out for you:https://bbs.pigoo.com/thread-86110-1-1.htmlAnother two possible substitutes??https://www.upi-semi.com/files/2189/0b350352-aa78-11ec-8d5f-d30ecdd7d08dhttps://www.upi-semi.com/files/2485/e38f7819-f8dd-11eb-8d5f-d30ecdd7d08dhttps://www.upi-semi.com/en-list-upi-620

author: Eg3300401
author_rank: Contributor
timestamp: November 03, 2022, 05:35:33 am
content: Worth a shot thank you!

author: fzabkar
author_rank: Super Contributor
timestamp: November 03, 2022, 05:42:38 am
content: See my latest edit.
Msi Rx570 armor 8gb - Page 1
Forum section: electronics / repair

author: gonzalezpereza
author_rank: Newbie
timestamp: February 13, 2020, 11:35:09 am
content: Hello everyone, I have a Msi rx 570 armor 8gb that stopped working, and I decided to give it a try and try to figure out what was wrong with it and try to fix it. So I started measuring all the power lines, and then I tried to check the enable signals in the buck converters since all what was missing seemed to be the power to the memory and the gpu, but while doing so I accidentally shorted something so a 2R2 resistor inmediatelly started smoking.So I replaced that resistor but now I have a short to ground in the 12V power line that I can't figure out where it is coming from.Any ideas or suggestions on how to continue? I am quite new to this kind of stuff and I think I ran out of ideas.I leave a couple pictures of the board. I have shown in the front one the resistor that I replaced.Thank you in advance for your help

author: gonzalezpereza
author_rank: Newbie
timestamp: February 13, 2020, 06:41:59 pm
content: Well, it seems I made some progress, it seems the two mosfets highlighted in yellow were shorted, I'm going to try to replace them with new ones and see what happens.I'll post my progress in case it can help somebody else.
MSI x370 Gaming pro m/b repair - in progress - Page 1
Forum section: electronics / repair

author: Nexxen
author_rank: Regular Contributor
timestamp: March 29, 2023, 09:55:25 pm
content: Hello,I have this m/b,- without a cpu it powers on; red LED on the cpu (meaning no cpu detected error)- with a cpu it doesn't power on.This is a normal behaviour for MSI boards when they cannot read the BIOS chip.The BIOS chip doesn't get its Vcc because of another failed component, one you helped me identify, CCH (MP5077GG). This outputs the Vcc for the BIOS.Another YTuber -Tech Cemetary, B450 - had this issue (), no Vcc = no power on.I wanted to read the BIOS chip but until I removed the CCH, I simply couldn't because of Vcc shorting to ground - this indicates that there is a short on Vcc 100%.After that I could read/write/test no problem.3 other components were dead and desoldered, ASM1408 (multiplexers).I have a few questions:- cpu mosfets (high) get the +12V, but the (low) mosfets don't output anything, is this a normal behaviour due to no cpu installed? (Nikos PK616BA + PK632BA groups (5 of these groups).- the fact that the MSI Eazy Led works, is a good indicator of something or just a mechanical response, and everything else could be dead?- without a multiplexer, is just the PCIe and M2 ports not working (thos connecting to the SB)? and everything else connected to the cpu lanes will?It's long but I'm a noob and can't 100% clear out all my doubts.Any help is welcome!!

author: Nexxen
author_rank: Regular Contributor
timestamp: March 29, 2023, 10:05:51 pm
content: I already ordered the new components, waiting to resolder and test.

author: Nexxen
author_rank: Regular Contributor
timestamp: April 19, 2023, 02:00:22 am
content: After getting help on how to resolder the CCH I could test the board.It didn't blow again, which is already something.The required voltage of 1.8V isn't being generated preventing the board from powering on (BIOS fails to init).I located another component that isn't outputting the 1.8V I suspect is required to trigger the CCH (like a Gate but I'm not sure).I'll order that one QFN 12, MP2147GD-Zhttps://www.monolithicpower.com/en/documentview/productdocument/index/version/2/document_type/Datasheet/lang/en/sku/MP2147GD-Z/document_id/835/I've learnt many things up to now, I take this as win-win even I fail to revive this board.Next post will be after resoldering the QFN.

author: Nexxen
author_rank: Regular Contributor
timestamp: April 19, 2023, 09:49:27 pm
content: This other smd gets terribly hot, impossible to stick my finger on it.It should output 1.8V but only 0.45V come out.I guess that it's either broken or another component is dead and shorting to Ground.I also have a GS7133 to check. As I'm learning things I do understand more and more but still too far from knowledge.
MSI Z690-A Pro no SLP_S3 - Page 1
Forum section: electronics / repair

author: Weissnix4711
author_rank: Newbie
timestamp: June 10, 2023, 03:03:05 pm
content: Hi,My MSI Z690-A pro DDR4 motherboard is showing no signs of life. SIO is the NCT6687D, for which I have no datasheet. I'm just going off net names from the boardview I have for this mobo and the datasheet of the similar NCT6686D.All relevant power rails seem good, incl. 5VSB and 3VSB. When PSIN# is pulled low, the PSOUT# signal is pulled low by the SIO. However, the chipset appears to do nothing. SLP_S3# and SLP_S5# always remain low.VSB is good. The RTC crystal is working, RTCRST# and RSMRST# are high. Any ideas what else may be preventing the chipset from pulling SLP_S3 low?I have very little understanding of this power sequence, I'm just trying to follow the datasheet the best I can. Any info is appreciated.Thanks,Thomas
MSO4014 Rotary Encoder Switch - Page 1
Forum section: electronics / repair

author: vinovino
author_rank: Contributor
timestamp: June 18, 2024, 10:18:02 am
content: I have an MSO4014 that has a problem with Horizontal position rotary encoder switch.Has anyone of you know the part number of the rotary encoder switch or tried to replace it with other replacement part?I tried to pull it out to find any markings but there is none.Please see attached actual images for reference.

author: squadchannel
author_rank: Frequent Contributor
timestamp: June 18, 2024, 11:32:04 am
content: Noble SDB161 maybe.It would be difficult to find one with exactly the same specifications.It doesn't have to be the exact same encoder.although the clicks, etc would change. It is possible to similar encoder and with bodge wires.

author: 2N3055
author_rank: Super Contributor
timestamp: June 18, 2024, 11:54:11 am
content: It looks like ordinary encoder without push switch. There is a good chance any standard encoder would do.Just get one that has same thread and shaft type and length, mount it with nut and connect it with wires to PCB. Of course it has to have enough space behind the PCB for it to fit.Getting original is not going to be easy, and these were not sold as parts ever, only whole PCB as subassembly.If you get a good quality encoder, chances are it is going to last longer than original one.

author: coromonadalix
author_rank: Super Contributor
timestamp: June 18, 2024, 03:50:48 pm
content: one thing to consider, you have 12 ticks per turn and 24 on other models ...
MSO4104 Repair - Black Screen - Page 1
Forum section: electronics / repair

author: darkmatter
author_rank: Newbie
timestamp: January 11, 2020, 08:54:41 pm
content: Any idea what manufacture made this part? Datasheet?Thank You!

author: Jwalling
author_rank: Unknown
timestamp: January 12, 2020, 10:34:50 am
content: Looks like Siliconix.https://www.digikey.com/product-detail/en/vishay-siliconix/SI7888DP-T1-E3/SI7888DP-T1-E3-ND/2622573
MSO8104A self test fails but passes self calibration. - Page 1
Forum section: electronics / repair

author: super_electron
author_rank: Contributor
timestamp: July 16, 2022, 10:16:42 pm
content: Hi dear eeblogers, I am trying to debug self test failure on a MSO80104A. For all practical purpose scope seems to be working and passes self calibration but when I run the self test it fails the vertical test group. The logs from the selftest results are attached. Your insight in debug this issue is greatly appreciated.Thanks

author: m k
author_rank: Super Contributor
timestamp: July 19, 2022, 02:00:03 pm
content: Is the model type correct?Google can't find a thing.

author: super_electron
author_rank: Contributor
timestamp: July 21, 2022, 05:48:07 am
content: Sorry it looks like there was a typo. the correct model number is MSO8104A. I compared the logs of self test from a good scope with the failed one but I can't find any difference in expected measured values except the vertical failed message.

author: m k
author_rank: Super Contributor
timestamp: July 21, 2022, 12:42:40 pm
content: Ok.Manual is also very helpful, Does vertical test group pass? -> No -> Replace acquisition board.From me any insights are pretty far out of sights, folks hanging around Test Equipment and Metrology sections have much more of that, but anyway.Is there a different test set for digital side?Fast reading the manual didn't give anything.Maybe it's as simple as vertical selection that is not propagating correctly inside the machine but is still actually operating totally correctly.Like when machine is used normally that test feature signal or its feedback is not used and is so irrelevant.
MSO9254A won't power on. - Page 1
Forum section: electronics / repair

author: yoyobob24
author_rank: Contributor
timestamp: May 27, 2025, 12:59:28 pm
content: So I got a MSO9254a form a local place that said try to fix it if you can then I'll sell it for pennies on the dollar to you.( They said they are paying for the parts to fix it)I just pulled the back off. Seems LED 1 2 3 4 are on on the debug led on the aqusition board. I tried reseating the connectors and using some contact cleaner on the but still nothing. Has any ran into this issue before? Should I just try to find a replacement psu?

author: MadTux
author_rank: Frequent Contributor
timestamp: May 27, 2025, 05:23:14 pm
content: Measuring PSU voltages certainly is a good start.Apart from that, Keysight is throwaway trash nowadays, without schematics, just get a Rigol or Sigilent, makes throwaway costs much less painful.

author: yoyobob24
author_rank: Contributor
timestamp: May 28, 2025, 04:30:41 am
content: Seems I just needed to reseat literally every single connector....did find a wire that is in pretty bad shape going to replace that and hopefully that be that last of my issues.Easiest repair of my life lol.

author: Runco990
author_rank: Frequent Contributor
timestamp: May 28, 2025, 03:08:23 pm
content: Quote from: MadTux on May 27, 2025, 05:23:14 pmAnd yet, ebay sellers STILL want $12,500 for a used one. I have both a 2000 series and a 7000 series. I have to admit, while the scopes perform very well and do everything I could ask for, the physical build quality is terrible. I have a Rigol 2000 series that the plastics are not deforming on....If I had to pay retail for one of these, having had them apart I'd NEVER buy one. They REALLY cut corners at some point in time. The HP and early Agilent stuff was amazing, and SOLID!The value of Keysight even used today is questionable.....

author: yoyobob24
author_rank: Contributor
timestamp: May 29, 2025, 02:22:01 am
content: Luckily its an Agilent.I did get it for dumb cheap tho ~3k usd. now to find the options unlocking.
MSOX3014A PSU and infinite reboot loop – possible NAND issue? - Page 1
Forum section: electronics / repair

author: NorwegianRF
author_rank: Contributor
timestamp: May 10, 2025, 01:31:51 am
content: Hi,I came across an MSOX3014A with a broken power supply, which I understand is quite common. Before ordering a replacement (Murata PQC250-12), I tried powering the scope using an external 12 V supply. However, the unit enters an infinite reboot loop — see the attached video:Could this behavior be caused by a faulty NAND chip, or are there any other known issues that could cause this? I’ve logged the current draw, and it doesn’t exceed 3.5 A during a boot cycle.Any tips would be greatly appreciated!Best regards,Stian

author: ita4ever
author_rank: Contributor
timestamp: May 10, 2025, 10:08:46 am
content: Quote from: NorwegianRF on May 10, 2025, 01:31:51 amHow did you logged the current?I mean: another scope or just a 100ms data-loggerQuote from: NorwegianRF on May 10, 2025, 01:31:51 amYou could check if MSOX3014A is able to boot from USB.If so you can run something from there (external flash) in order to check if your temporary solution with +12V external power supply is ok.Some digital equipment can boot from USB and even run doom. e.g.Doom also runs on DSOX Keysight oscilloscopes, see here:https://hackaday.com/2018/10/18/playing-doom-on-keysight-oscilloscope-via-windows-ce/

author: Simon
author_rank: Unknown
timestamp: May 10, 2025, 05:08:56 pm
content: Please do not double post.
MSOX3054 bootup problem - Page 1
Forum section: electronics / repair

author: Drirr
author_rank: Regular Contributor
timestamp: November 19, 2019, 12:10:01 pm
content: Hi guys,My friend brought MSOX3054 to me several days ago and he asked me for fix.Symptoms: Oscilloscope get stuck on bootup - after cycling several LEDsI found that this problem is probably caused by NAND FLASh memory.i know that there are some ways to reprogram NAND memory on this forum but most of links to FW are dead ( 404 - not found )Is there any simple way to reprogram memory?Thanks
MSOX4034 hardware self test failure - Page 1
Forum section: electronics / repair

author: myhobo
author_rank: Regular Contributor
timestamp: December 01, 2019, 02:35:28 pm
content: MSOX4034 hardware self test failure. picture display：Self-test failure：DigComp

author: myhobo
author_rank: Regular Contributor
timestamp: February 16, 2020, 11:19:55 am
content: I have found this problem. The comparator chip of the logic analysis circuit is broken. I found this chip from taobao.com and can use it after changing it.

author: myhobo
author_rank: Regular Contributor
timestamp: February 16, 2020, 11:25:44 am
content: The hardware test pass in this time.

author: myhobo
author_rank: Regular Contributor
timestamp: February 17, 2020, 01:50:14 am
content: Agilent MSOX4034A Oscilloscope Logic analysis function repair vedio:

author: Mr. Scram
author_rank: Super Contributor
timestamp: February 17, 2020, 02:05:51 am
content: Thanks for showing us!
MSP430 not starting in MS6816 - Page 1
Forum section: electronics / repair

author: goaty
author_rank: Regular Contributor
timestamp: October 26, 2020, 08:34:02 am
content: Hi all,I´ve got a cable tester Mastech MS6816, where the receiver part does not power on.I found out that the Texas Instruments microcontroller MSP430F135 has a 4MHz clock which oscillates,but there is initially no activity whatsoever on it´s outputs, specifically to the display.When I stop the clock by shorting the crystal, it comes alive for two seconds and the display is initialized and the device beeps,but then freezes again.I tried another crystal and also added some 15pF caps to it, but that did nothing.Display shows some plausible stuff, but it does not react to keypresses and also not to the reset pin of the microcontroller.I have not yet tried JTAG, but wanted to ask the community if there is any hint in what this bahaviour of the micro could cause.Is it more likely dead chip or is the firmware corrupt ? What could it be that it does not react to the RST pin ?The sender works fine and there the same processor is used and the RST pin just works fine.Thanks for any hints.Thomas

author: Psi
author_rank: Super Contributor
timestamp: October 26, 2020, 08:38:11 am
content: They might be using the RST pin as GPIO, would explain why you don't get a reset when you trigger it.Other thing that might cause RST pin to be ignored is a low voltage triggering brown out to hold RST active.Could also be a GPIO line which is in an odd state due to a fault and is locking up the startup sequence.
MT4080A - Page 1
Forum section: electronics / repair

author: Luzbel
author_rank: Newbie
timestamp: October 04, 2020, 02:32:04 am
content: Hello, my name is Jonathan. I am from Chile. I am passionate about electronics, always learning.A query I have a lcr mt4080A of about 15 times that I turn it on, it stays in the logo, I restart it and everything is fine. someone who has and knows about this machine? Ty

author: coromonadalix
author_rank: Super Contributor
timestamp: October 05, 2020, 01:20:54 am
content: seems a clone of an BK precision 885 886You have a thread here and schematics at ko4bb websitehttps://www.eevblog.com/forum/repair/identify-theses-masked-buffed-ics-need-search-detectives-gurus/

author: Luzbel
author_rank: Newbie
timestamp: October 05, 2020, 02:53:25 am
content: Ohh! ty so muchi will see.
MTS 407 controller service manual - Page 1
Forum section: electronics / repair

author: rvalente
author_rank: Frequent Contributor
timestamp: July 26, 2019, 12:44:18 pm
content: Hello mates,Ive 3 faulty MTS 407 controllers, does anyone have the service manual for sharing/sale?GreetingsSent from my LG-H870 using Tapatalk

author: rvalente
author_rank: Frequent Contributor
timestamp: August 03, 2019, 02:39:20 pm
content: Anyone? Im willing to pay!Sent from my LG-H870 using Tapatalk
Multi-Meter Calibration Chicago - Page 1
Forum section: electronics / repair

author: RiceandBeanz
author_rank: Newbie
timestamp: March 03, 2025, 10:19:42 pm
content: I'm currently waiting on a battery for my HP 3478A.I've called around and most of the labs want $300 for calibration. I understand that they're dealing professional labs rather than hobbyists.Is there anyone in Chicago who knows of an affordable calibration service?I'm also frustrated that there isn't a supply of components in the City. Micro-Center doesn't even cut it. You'd figure with a City as large as Chicago, there would be a component supplier around.Also, Hello! I've been on AudioKarma for a while, but I'm diving deeper into the hobby, which requires a greater knowledge of electronics, so here I am

author: bdunham7
author_rank: Super Contributor
timestamp: March 04, 2025, 06:31:25 am
content: Quote from: RiceandBeanz on March 03, 2025, 10:19:42 pmDid you lose the cal data? There used to be a few labs out here in SoCal that would do a "no adjust" (test only, w/ data) for under $100 on 5.5 and 6.5 digit meters but IDK if they still do. The price would double if adjustment was required, so perhaps $300 is just inflation over the past few years. Yikes!There aren't really any retail component suppliers anywhere AFAIK, even here in LA. However, availability in online markets is better than ever IMO.

author: krish2487
author_rank: Frequent Contributor
timestamp: March 04, 2025, 01:03:20 pm
content: How critical are the 5.5 digits for your work??I mean its nice to look at 6 digits on the multimeter... but how critical is the 10 microvolt or 10 microamp to your work??I mean... if its simply a question of checking how much you are out by and noting it down... you have plenty of cheap ebay references that you can do a 4.5 digit confidence of measurement on your 5.5 digit multimeter...well atleast for dc v... and with some effort you can do ac v..now the current is a different beast entirely..

author: Kleinstein
author_rank: Super Contributor
timestamp: March 04, 2025, 04:17:33 pm
content: An adjustment at the proper cal lab may well be more expensive than such a meter is worth / costs. Especially older meters are sometimes a bit more difficult to get adjusted as they don't have automation for them - the 3478 at least already has digital adjustment.Only a crude DIY adjustment to some ref. source / other meter is a real option - the 3478 still offers good resolution for small signals with it's 30 mV range.I kind of have a similar issue with my DIY meter: good resolution (like 7 digits) but relatively poor absolute accuracy (maybe 0.2 % range).It is relatively rare that one needs the high accuracy / absolute scale.
Please help in repair Multicharger 1500 ELTEK NO CURRENT READING In Display - Page 1
Forum section: electronics / repair

author: HUGOMAN
author_rank: Regular Contributor
timestamp: February 07, 2024, 08:04:43 am
content: HII have repalaced some of diodes and transistors, the multicharger gives a voltage 12/24v when i apply a load who is 12V battery the current displays is 0.00A. the middle yellow led is flashing not on.Thanks and Regards

author: HUGOMAN
author_rank: Regular Contributor
timestamp: February 08, 2024, 08:42:35 pm
content: please i am waiting for your help !

author: HUGOMAN
author_rank: Regular Contributor
timestamp: February 11, 2024, 09:19:07 pm
content: It's a big surprise ! what's happen nobody can give a solution to the issue or even give a remark
multicomp mp710086 DC power supply giving fixed out of 0.183V only - Page 1
Forum section: electronics / repair

author: nudist
author_rank: Newbie
timestamp: November 22, 2021, 10:17:00 am
content: Hi,I am a newbie in electronics so I understand I am far away from able to fix anything.I had bought Multicomp mp710086 DC power supply this year. It was working perfectly. After transporting it from another city, it is not working any more. The display and buttons are all good but the output is always giving 0.183V. The output stays the same when I connect or without a load in the output terminals. This voltage is shown in the LCD is also 0.183V and I have also verified it with my multimeter is same.I thought during transport, some wires might have come off from their sockets, so carefully I opened it and just glanced inside. Found no loose wires.The device has a mains power button, and push button for output. So only when output is pushed on, does the output start, but always stays at the same point. I can adjust the voltage and current (it has max 5A) and output shows 5A but same 0.183V.Any guesses on what could be the problem?Thanks a lot.Vikas

author: ESTechnical
author_rank: Contributor
timestamp: November 22, 2021, 12:39:31 pm
content: Hi Vikas,This sounds a lot like a reverse polarity protection diode across the output has become shorted. I presume the psu is not lying about the 5A output, it may well be supplying 5A into this short and the small voltage you see is the voltage drop of the short. Check for shorts with a meter, working backwards from the output terminals.HTH,Ed

author: Electrump
author_rank: Contributor
timestamp: February 18, 2023, 09:29:05 pm
content: Hey NudistHave you figured out what was wrong with the power supply?
Multicompro MP710086, 30v, 5A Programmable bench power supply  - Page 1
Forum section: electronics / repair

author: MAHESH BABU T
author_rank: Newbie
timestamp: July 21, 2021, 01:21:06 pm
content: Hi,I had purchased Multicompro MP710086, 30V, 5A Programmable bench power supply from M/s. TANOTIS, Bangalore, India in the month of 01/2021. Unfortunately the liquid in the 3.7" TFT LCD screen have been started leaking from top left corner and the digits are not visible properly. I have contacted the above supplier for arranging rectification of the same, but no positive response was seen and they have replied that contact the manufacturer for after-sales service since the above product is within the warranty.I could not find the manufacturers of the above product in Asia pacific region. And having thorough search, I find that the authorized dealers / supplier of the above make products at element14.com, Bangalore, India. Finally I have contacted the service support at element14.com, and they have replied that they will support/service the products which have been purchased from them only.I really disappointed and seeking help from somebody to resolve issue and availability of new TFT 3.7" LCD display to purchase please.Regards,MAHESH BABU T+919490153084.

author: shuvodutta
author_rank: Contributor
timestamp: July 21, 2021, 04:16:49 pm
content: Hi Mahesh,Welcome to the forum.Your 'Multicompro MP710086' looks like a rebranded Owon P4305. Owon may even be the O.E.M. for other suppliers/brands but I'm not sure. It may be difficult to get a replacement T.F.T. L.C.D. for this unit directly but there are many reviews & tear-downs available for P4305 (some of them are on this forum.). You may be able to spot the part no. of that T.F.T. L.C.D. from these sources & order that part accordingly. Best of Luck.Tanotis is just a platform which aggregates different vendors/manufacturers across the world, they're not 'Manufacturing' anything. Getting support (including warranty) may be difficult to get other than from manufacturer/original supplier.
Multimeter always OL - Page 1
Forum section: electronics / repair

author: AcM
author_rank: Contributor
timestamp: February 25, 2024, 02:59:41 pm
content: Hi all,I've a multimeter Vemer VE8020, it's based on the tc820clw ic.Suddenly in all selector position it shows on the display OL.No burned components or visible damage, as the issue affects all the measurements, I'm focused on the reference or maybe I'm wrong, I noticed that never changes the value changing the range.Any idea o suggestion?Regards

author: markusdd
author_rank: Contributor
timestamp: February 25, 2024, 06:38:11 pm
content: as an idea: could also be of mechanical nature, i.e. cracked solder joint(s) somewhere, as there is a whole lot of THT components I think this would be worth a look.also, the big fuse holder also looks a bit unhappy/corroded, maybe it's just a contact problem there?

author: Jwillis
author_rank: Super Contributor
timestamp: February 25, 2024, 10:24:39 pm
content: Could be probe leads have break in wires. Set multi meter to continuity and plugged one probe lead into a port and probe the other port. Repeat with the other probe.

author: DaJMasta
author_rank: Super Contributor
timestamp: February 25, 2024, 10:54:50 pm
content: Just to be sure, you've checked the battery too, right?

author: AcM
author_rank: Contributor
timestamp: February 26, 2024, 05:42:15 pm
content: Hi all,thanks for the reply, battery is ok and also the leads are ok.I went through all the solder joints but nothing changed.Any other hints?

author: rsjsouza
author_rank: Super Contributor
timestamp: February 26, 2024, 06:17:41 pm
content: If it shows OL on volts and current, then any issues on the input circuit can be ruled out - after all, disconnects and bad contacts would show instead "0" (zero).My suspicion would be something on the upper digital side of the equipment, more specifically in the Vin pins of the TC820 (datasheet is available). I would start measuring the input voltage across both pins and see if it is too high (the datasheet would give additional info, but it is probably 200mV) and measure backawrds from that point in case the voltage is indeed too high.In case the voltage on the ddvice is zero, then I would suspect the TC820 is damaged.Good luck in your repair
MULTIMETER AMECAL ST-9905 - Page 1
Forum section: electronics / repair

author: lionelkjh
author_rank: Frequent Contributor
timestamp: February 11, 2024, 02:43:00 pm
content: Good evening everyone!! I'm looking for someone who owns an AMECAL ST-9905 multimeter, and I need fairly large photos of the board (component side) of the entire multimeter... A big thank you to anyone who can give them to me... Thanks in advance!!

author: xrunner
author_rank: Super Contributor
timestamp: February 11, 2024, 03:03:49 pm
content: Why are you asking the same questionagain?https://www.eevblog.com/forum/metrology/multimeter-amecal-st-9905/?topicseen

author: lionelkjh
author_rank: Frequent Contributor
timestamp: February 15, 2024, 08:06:16 am
content: HELP!

author: Swainster
author_rank: Frequent Contributor
timestamp: February 15, 2024, 09:40:29 am
content: I don't have this meter but image search suggests that it is available under at least 3 different brand and model numbers.Have a look at one of Big Clive's videos - there may be enough info in it for your purposes (whatever they are)https://youtu.be/QMEeB-WVdbw

author: lionelkjh
author_rank: Frequent Contributor
timestamp: February 15, 2024, 11:54:17 am
content: Good morning; thank you for your kindness! I have already watched this video, and I sent my request by email to the owner of this multimeter, but since Sunday, I have not heard back...Cdt

author: lionelkjh
author_rank: Frequent Contributor
timestamp: February 16, 2024, 04:35:18 pm
content: Good morning; it seems that a more recent correspondence of this device is of the brand CEM DT9905 (Chinese group I believe)....If anyone has it.....Cdt

author: lionelkjh
author_rank: Frequent Contributor
timestamp: February 23, 2024, 02:28:51 pm
content: Good morning; I made progress this afternoon in my troubleshooting; and the culprit is D17! (zener I think; I'm posting the photo), can someone do tests on their multimeter to find its value?? And also can you tell me how much power it consumes when starting up? Thanks in advance
multimeter fluke 117 voltage measurement error - Page 1
Forum section: electronics / repair

author: KKTHUONG
author_rank: Newbie
timestamp: January 30, 2023, 08:08:39 am
content: My Fluke 117C is showing OL flickering when measuring AC, DC and mV. I have checked the RT and MOV, both have no damage. I have opened the circuit board also no shorting problem. Is my device fixable? Can anyone help me out.https://imgur.com/a/WBIcFfI

author: guswin95
author_rank: Contributor
timestamp: January 31, 2023, 08:47:32 pm
content: Hello,Could you open it up and take good pictures of the board both sides?Therefore, we can see if anything is amiss.Cheers

author: KKTHUONG
author_rank: Newbie
timestamp: February 01, 2023, 02:11:29 am
content: I opened it up and checked the components. I can define meter using voltage and current measurement functions. It will show OL.https://imgur.com/a/ZFDHnnY

author: R-1125F
author_rank: Regular Contributor
timestamp: February 02, 2023, 03:08:58 pm
content: Do other functions work OK?

author: bdunham7
author_rank: Super Contributor
timestamp: February 02, 2023, 03:50:39 pm
content: Quote from: KKTHUONG on January 30, 2023, 08:08:39 amYour video does not show what the leads are connected to. If it does this with no test leads attached, then try installing test leads and shorting them to see what you get then.

author: KKTHUONG
author_rank: Newbie
timestamp: February 07, 2023, 09:43:47 am
content: Resistance measurement and continuity function work OK. The functions related to the ADC all report OL. Function to measure A,mA,LOZ . I don't know if the ADC function is U2 whose code is LTFLK2.
MULTIMETER FLUKE 79III - Page 1
Forum section: electronics / repair

author: lionelkjh
author_rank: Frequent Contributor
timestamp: December 23, 2024, 04:44:49 pm
content: Good evening everyone! I am trying to identify the 3-legged smd component marked "99" on the attached photo of the FLUKE79III electronic card .... I am also attaching the general photo of the multimeter ... Could someone help me?? Thank you for your patience and dedication.F26III_007.jpg(249.89 kB. 1024x768 - viewed 211 times.)

author: Kurets
author_rank: Regular Contributor
timestamp: December 23, 2024, 05:37:03 pm
content: I would expect BAV99 dual diode for some kind of clamping to rail. Not sure as it would require a bit more reverse engineering.

author: bdunham7
author_rank: Super Contributor
timestamp: December 23, 2024, 06:38:46 pm
content: Maybe one of these:https://www.mouser.com/ds/2/348/ta115te-1144138.pdf?srsltid=AfmBOorylFTfy4NF8wXon6jhIjqR-98V7GoIDAnGMDe2VABJk1eTf_gN

author: lionelkjh
author_rank: Frequent Contributor
timestamp: December 25, 2024, 04:22:08 pm
content: Thanks a lot!

author: Psychodad49
author_rank: Newbie
timestamp: December 26, 2024, 09:09:57 am
content: I also have a Fluke 79III and opened it up. This is what the parts in my device look like, maybe this will help you.

author: lionelkjh
author_rank: Frequent Contributor
timestamp: December 26, 2024, 06:12:56 pm
content: Good evening; thank you for your feedback! I think that it must be a DTA115 transistor.....Cdt
Multimeter Input jacks - Page 1
Forum section: electronics / repair

author: hitecelec
author_rank: Regular Contributor
timestamp: May 18, 2024, 06:20:24 am
content: HelloAre fluke ot tek DMM Input Jacks (pcb Solderable) or equivalents available in red or black colorDoes Pomona make themThanks in advanceRegardsAnand