hybridfree/eevblog-posts huggingface dataset:
Graphics Card Repair - RX 5600 XT Pulse - Page 1
Forum section: electronics / repair

author: strelly83
author_rank: Newbie
timestamp: February 28, 2022, 08:14:33 am
content: Hi everyone, I'm strelly, a new forum user.I'm writing to ask for some advice on this graphics card that I would like to try to repair. It is a Sapphire Radeon RX5600XT PulseSuddenly the PC turned off and when restarted the card does not start (no power and fans stopped)I'm not very experienced in electronics, but after opening the card, I measured the continuity of the fuses and it seems that the fuse near the PCI Express connector has blown. There are actually 2 fuses nearby, the one that has problems I have circled it in red in the attached photo.I noticed that on the back of the board there is a voltage regulator (1117SA)... could that be the problem?What tests should I do? Can you help me? I'd hate to throw the card awayThanks to all those who want to help me!

author: TheMG
author_rank: Frequent Contributor
timestamp: February 28, 2022, 10:00:34 pm
content: Most likely culprit would be one of the VRMs U503-U507 has gone short.

author: Johnny10
author_rank: Frequent Contributor
timestamp: February 28, 2022, 11:16:47 pm
content: Don't forget to look on youTube for your graphics card. Graphics Cards come up quite often in repair videos.

author: strelly83
author_rank: Newbie
timestamp: March 04, 2022, 01:50:20 pm
content: Quote from: Johnny10 on February 28, 2022, 11:16:47 pmThank you! I've the same exact problem of the video, I tried to ask the model of the capacitor replaced on the board but I've not received any answer...Anyone is able to retrieve the model to be replaced? Are there any schematics of this card on the network?
Grey coating inside cabinet - Page 1
Forum section: electronics / repair

author: abhi1981
author_rank: Regular Contributor
timestamp: April 27, 2025, 06:31:39 am
content: What is the grey coating found inside every audio equipment with a metal cabinet?

author: Analog Kid
author_rank: Super Contributor
timestamp: April 27, 2025, 06:44:16 am
content: Anodizing or plating.What I wonder about is not the gray coating but that reddish-copperish finish seen on the inside of most audio gear.Same thing, I guess, but I wonder what substance it is.

author: Haenk
author_rank: Super Contributor
timestamp: April 27, 2025, 07:22:29 am
content: I'll put my money on "Zinc plated steel sheets" - a common material for 3D formed metal parts.https://amerexsteel.com/zintec/It's the easiest way to manufacture these parts - you can't use plain steel, as it would rust or would need further treatment, which is costly.

author: Coordonnée_chromatique
author_rank: Frequent Contributor
timestamp: April 27, 2025, 08:01:46 am
content: Quote from: Haenk on April 27, 2025, 07:22:29 amStocking unplated sheets of steel is very expensive, the sheets are galvanized before the stamping process in big rolls or sheets that have no costly requirement for the later processes.

author: Arts
author_rank: Regular Contributor
timestamp: April 27, 2025, 05:03:08 pm
content: The trade name is Satin Coat. It is a galvanizing coating that is wiped as it comes out of the bath.It was originally developed for Fender (for use in musical instrument amplifiers) by US Steel as an alternative for chroming or painting their chassis.
Grid 1450 Powersupply G43-4180 - Page 1
Forum section: electronics / repair

author: Retrobitsnbytes
author_rank: Newbie
timestamp: August 29, 2024, 12:41:05 am
content: Greetings !!! I am workig on repairing a Grid 1450 Laptop power supply model G43-4180. It is a Sanken power supply - PKG1 PS30132B M - I am hoping to find the schematic for it. Might anyone out there have access to this schematic and willing to share?
Grinell TR32 (GRC-102) info needed - Page 1
Forum section: electronics / repair

author: pag
author_rank: Newbie
timestamp: July 06, 2024, 11:17:54 pm
content: A friend asked if I could help him fix his GRC-102 HF transceiver, which I understand to be a Grinell TR32.It receives nicely on AM but just a low medium pitched hum on SSB.What I would like to find is a schematic for this section of the radio, the product detector (or whatever they use) and audio switching. I know where it is located in the radio and have done some probing.Does anyone have any idea where I might find this? Maybe a SA ham has some information?Peter
Groovy jellyfish lamp - Page 1
Forum section: electronics / repair

author: mad-elec
author_rank: Newbie
timestamp: December 22, 2023, 05:55:27 am
content: Hi all, my wife bought this jellyfish lamp a few months back and now its just stopped working.I've already changed the ac adapter but that wasn't the issue so now I'm looking internally.It doesn't look like a very complicated bunch of circuits, there is where you plug in the power adapter, the main circuit, an attached LED array and a small water pump motor.I've taken some photos and wondering if anybody can identify parts I might be able to replace that are common failure points?
Ground Loop Noise with Aeroflex 8310 Programmable Step Attenuator - Page 1
Forum section: electronics / repair

author: garrettm
author_rank: Frequent Contributor
timestamp: October 21, 2020, 12:06:52 am
content: So I got an Aeroflex 8310 programmable step attenuator for use with a project I'm working on and noticed some odd behavior when I connected it to my Agilent 89410A vector signal analyzer for verification of the attenuator ranges.The attenuator exhibits measureable noise from DC to about 1.5 MHz when the input is terminated into 50ohms or when the attenuator is set to a value greater than 0 dB. Some of this looks like it could be noise from the internal line filter and other parts look to be from the switchmode power supply. The power cables to each instrument have ferrite chokes on them and are connected right next to each other on the same power strip.Disconnecting the ground wire from the 8310 and using a DMM to measure the voltage between the 8310 chassis and earth ground I found 24.2Vac when off and 55.8Vac when on. Into 1Mohm of the DMM, thats about 24uA of ground current when off and 56uA when on. This ground current looks to be what's causing the observed noise on the VSA.Connecting a heavy guage aligator cable between the chassis of the ungrounded 8310 to the earth grounded VSA chassis lowered the noise but did not eliminate it.I did a similar test with my HP 6236B PSU and found 8Vac off and 12Vac when on (between chassis and earth ground). That's significantly lower than the Aeroflex 8310 attenuator.Is this sign of a bad line filter and would replacing it fix this issue? Would I need to replace the X and Y caps on the SMPS as well? Or is this something that isn't going to go away?

author: pharbour
author_rank: Newbie
timestamp: July 02, 2025, 06:54:00 am
content: Hi garrettm,Ferrite clamps on the AC-Mains wiring could introduce small voltage spike energy on the 8310 Earth-GND connection, introducing the noise you mention. I would guess the 8310 SMPS has isolated primary to secondary, you shouldn't see a lot of energy into a 50 ohm load unless the SMPS has a problem. I assume the 8310 is quite low power.You will see sizable AC voltages if you float the secondary side.You are sure the Earth-GND wiring of your AC-Mains and power strip is connected?
GSP-930 GW Instek Spectrum Analyzer not starting up - Page 1
Forum section: electronics / repair

author: Sixten
author_rank: Newbie
timestamp: February 08, 2025, 03:49:59 pm
content: Hi,I have a GSP-930 GW Instek Spectrum Analyzer that won't start.Pressing the on/off-switch starts up all voltage rails and they all are ok.On the mainboard containing a FPGA I connected a UART to see if the boot-sequnce could get me some leads and according to attached dump it seems that the FPGA doesn't manage to start correctly.A far as I understand the FPGA (XC3SD1800A-4CS484LI) is loaded by an externaly memory wich means if it's faulty or have a bad soldering underneith it should be possible to replace without having it programmed.I know this model have kind of a "well known" issue, since I've seen several 930 with this same boot-problem and the only solution is to ship it for repair.Anyone that's familiar with this issue or hints what to check?
GTX 1070 AERO 8GB No post Cpu fan spin 1 cm - Page 1
Forum section: electronics / repair

author: CAPSBOY
author_rank: Newbie
timestamp: February 07, 2023, 08:14:47 pm
content: HiMy Aero I acquired in a lot of cards has a lovely no power issue, when inserted the CPU will spin for a sec and nothing else,Could it be the fuse that's blown ??No burn marks on card that I can see,Photos of card enclosed.

author: simba15
author_rank: Regular Contributor
timestamp: February 07, 2023, 09:19:36 pm
content: Test for shorts on the power rails?Usually If a GPU was giving me issues I would re-flow the GPU and it has solved many issue in the past ( but this is only when the card boots and has issues with display)Best of luck.

author: CAPSBOY
author_rank: Newbie
timestamp: February 07, 2023, 09:24:06 pm
content: Quote from: simba15 on February 07, 2023, 09:19:36 pmThanks for that .. yeah I think I’ll get my multimeter out and test for shorts .. might be something small pulling down the voltage and making the card short the motherboardCheersAny more help please comment below

author: CAPSBOY
author_rank: Newbie
timestamp: February 08, 2023, 10:59:01 am
content: And I cleaned and put in to Test and …… smoke and sparks ⚡️

author: wraper
author_rank: Unknown
timestamp: February 08, 2023, 11:15:36 am
content: Quote from: simba15 on February 07, 2023, 09:19:36 pmHell no. It worked only on some older GPUs which failed internally and heating brought them back to life temporarily. On 1070 reballing only works on graphics cards which were dropped and more likely that solder under RAM will fail first. Baking these series is a very dumb way how to make useless trash out of repairable graphics card. Fuses even when fail, they don't do it by themselves. If there is a blown fuse, you're up to something more serious. First thing you need to do is check power rail resistances to GND.

author: wraper
author_rank: Unknown
timestamp: February 08, 2023, 11:19:38 am
content: Quote from: CAPSBOY on February 08, 2023, 10:59:01 amLooks like there was a shorted ceramic cap which was very easy and cheap to replace. But now it's probably a PCB burned through he layers. Clean that and post a photo of how bad it is.QuoteYou are not supposed to power a graphics card which makes computer to turn off unless you want to cause more damage.

author: CAPSBOY
author_rank: Newbie
timestamp: February 08, 2023, 11:35:28 am
content: Quote from: wraper on February 08, 2023, 11:19:38 amyeah dumb move by me but I had a feeling it might live after a clean .. silly me.. I can pull it off with my hot air station and retake picsCheers
GTX 1070 mini OC capacitor short to the ground? - Page 1
Forum section: electronics / repair

author: Gilberto
author_rank: Newbie
timestamp: January 22, 2022, 01:12:28 pm
content: Hi Guys!I have a 1070 GV-N1070IXOC-8GB videocard, and it has the following symptoms:Nothing spins, no fann nou output.The pci bus does not recognise it.But:There is no visible burn markt anywhere, the powerrail is not shorted to the ground.In my assumption, the gpu resistance is not shorted, and the memory resistances seems to be fine.The board has 4 caps, which share a common ground, three of them are connected to the 12 v as expected, but the fourth is shorted. I have removed the cap, but it seems, that the short is elswhere.Does anyone have any idea how this can be?I mean that, the cap that I took out does not seem to be connected to the 12V rail.In my assumption, I must first find the short to the ground, and the find the missing 12v connection? I am lost.

author: wraper
author_rank: Unknown
timestamp: January 22, 2022, 01:24:08 pm
content: Resistances measured seem more or less ok since it's vcore and vram. Check if there is no faulty MLCC like discussed herehttps://www.eevblog.com/forum/repair/gigabyte-gtx-1070-mini-no-fan-spin-no-video-dead-cap-found/

author: wraper
author_rank: Unknown
timestamp: January 22, 2022, 01:28:49 pm
content: Photo is blurry but C178 seems to have a crack or some dirt on it.

author: Gilberto
author_rank: Newbie
timestamp: January 22, 2022, 01:32:15 pm
content: That's what I noticed too, however I wasnt sure, if that could be responsible for it. I will try to desolder it without damaging the board, but I have limited skills.

author: Gilberto
author_rank: Newbie
timestamp: January 22, 2022, 02:42:13 pm
content: Sooo I took down 177, and the short disappeared.However, the cap "left side" still isn't connected to the 12v rail directly, is it possible?

author: wraper
author_rank: Unknown
timestamp: January 22, 2022, 02:44:12 pm
content: Read the other thread I gave the link to. There is a blown fuse.

author: Gilberto
author_rank: Newbie
timestamp: January 22, 2022, 02:58:26 pm
content: I read, it and I checked it, but visually it was ok, but now I checked with multimeter, and its actually blownAnyway, I will buy a new one and replace it, also based on the thread, tha capacity should be around 4.7uF 16v.However if I read it correctly, it might not be necessary?Do you think I could just run it without that single cap?

author: wraper
author_rank: Unknown
timestamp: January 22, 2022, 03:17:32 pm
content: It will still work without a cap but it's better to replace it.

author: Gilberto
author_rank: Newbie
timestamp: January 22, 2022, 03:35:19 pm
content: Thanks for all the help, I gues I 'll have to wait, cause its 8 days until I get my fuse....But thanks for the help!
GTX 1080 FE repair, now i am stuck..... - Page 1
Forum section: electronics / repair

author: Tadango
author_rank: Newbie
timestamp: June 22, 2020, 05:51:34 pm
content: I bought a defective GTX 1080 FE to see if i can figure out what is wrong with it (for fun, it was cheap). Symptoms when i received the card: No output in post / detection by Windows, fan always at 100%. Not heat from the card.I don't know the history of the card but there is a dent in the back cover. That back cover has a protective plastic film in which 2 capacitors from the 2x PCIe lane were stuck / jammed, and ripped of the PCB. Other then that the card looks perfect.So first things to check were power and resistance, but all looked good (VCore, VMem, PEX and PLL). Voltages were spot on and the resistance is the same or slightly higher then what is reported online, so no worries about a shorted component. With the heatsink removed the GPU does get slightly warm with my finger on it, but not hot at all, so it isn't doing much.I checked the bios chip and i can read / write it without any errors. It also contained the original bios in the first part but garbage in the second part. I cleared the chip and flashed the correct bios to make sure, but that didn't change anything.Next i hooked up my scope (Rigol 1054Z) to the CS, CLK, Data in and Data out of the eeprom chip but that doesn't show anything. Only CS is high, the rest is low. Since CS is active low it means the chip isn't even selected.So this looks like the GPU is not starting at all, like it is stuck in a reset state. It get's power so i wonder what could be keeping it in the stuck state? I tried to trace the B11 line from the PCIe slot (Power Good signal) but it disappears in a via and i cannot find it again.So..... what else can i check? GPU die is perfect optical, no cracks or chips. Cooler was not removed before (screws were sealed). Maybe the card was dropped and caused the GPU to make bad contact? Is the next step a reflow? I got a reflow gun so that is one thing i can try.....
Gtx 770 no signal - Page 1
Forum section: electronics / repair

author: more_stars
author_rank: Regular Contributor
timestamp: April 17, 2020, 09:28:56 am
content: So, after using this card for just 3 days, I came home today and seen that the card is not giving any output. I tryed using the igpu but the gtx 770 is not even recognised by the system.I checked the vrm voltages and seen 1.5v on the vrm near the video outputs and 0.8v on the cre vrm. I don't know exactly if the 0.8v is a good voltage as after some research, I see that the defoult voltage is 1.2This card was broken and had all the ceramic capacitors from the 12v blown and after replacing them, the card worked again.From the ground to the + of the caps, I was able to see around 470ohm but now, the reading is in range oh kohms și there bust be something that failed.Regards Alex

author: more_stars
author_rank: Regular Contributor
timestamp: April 17, 2020, 11:12:32 am
content: I just plugged my gtx 770 into my brother's computer and it was working fine. I plugged an HD 6850 into my ps and it was working fine so the pci e port is fine.Whst can it be?Also, I was able to see that in his computer, the core vrm stayed at 1.1v
GTX 780 missing capacitors - Page 1
Forum section: electronics / repair

author: didi79
author_rank: Contributor
timestamp: May 05, 2021, 04:40:23 pm
content: Hi. I'm new to this forum.I have an old GTX 780 that's missing a few capacitors on the PCIE lanes. Obviously causing the GPU from being detected.I don't have a capacitance meter. Does anyone have an idea what type they are or what values they may be ?

author: dc101
author_rank: Regular Contributor
timestamp: May 05, 2021, 05:09:39 pm
content: Can you post a picture of the section of board missing the caps? Also who makes your video card?You could try doing some google searching for the capacitor number (CXXX) and the name of your card. There's been a few prior threads on this forum regarding video cards.

author: wraper
author_rank: Unknown
timestamp: May 05, 2021, 05:16:33 pm
content: Usually they are 220nF, value is not critical.

author: didi79
author_rank: Contributor
timestamp: May 05, 2021, 06:06:44 pm
content: Wow fast responseCan't really see a brand, it's pretty much the reference design.You can see the missing caps (well, you can't see, because they are missing...) near the screw with the sticker on.

author: mariush
author_rank: Super Contributor
timestamp: May 05, 2021, 06:33:27 pm
content: Should have the same value as the ones above (the same values used on each pci-e lane)So it would be enough to desolder a pair from above, measure capacitance with a decent multimeter and solder capacitors of equivalent capacitance.Size is small .. probably less than 0402 but you could bodge bigger sizes with a bit of soldering skill and patience.

author: didi79
author_rank: Contributor
timestamp: May 05, 2021, 07:37:00 pm
content: Ok thank you.I better invest in a capacitance tester if I want to do more repairs like this ;-)

author: didi79
author_rank: Contributor
timestamp: May 08, 2021, 01:17:41 pm
content: Could not wait for delivery of the capacitance tester... So I took some SMD caps from a donor card that looked very similar.Card is detected correctly now and I've been stresstesting it for a few hours now. Seems rock solid.I guess most cards will indeed use similar caps there, since they all serve the same purpose (pcie lanes).Thanks again

author: dc101
author_rank: Regular Contributor
timestamp: May 11, 2021, 03:07:03 am
content: Glad you were able to fix your card! I guess it makes sense that they are probably all the same, since they seem to exist for pcie signal conditioning which I would assume is somewhat universal across pcie cards. Probably they are more critical in higher performance, higher speed pcie cards.

author: wraper
author_rank: Unknown
timestamp: May 11, 2021, 09:31:00 am
content: Quote from: dc101 on May 11, 2021, 03:07:03 amIt's not for signal conditioning but for AC coupling. Considering PCI-E high operation frequency, basically any MLCC cap will work unless capacitance is too small.
GTX 780 TI short - Page 1
Forum section: electronics / repair

author: pepelepe
author_rank: Newbie
timestamp: November 17, 2019, 09:01:35 am
content: hello, I have a gtx 780TI and apparently it has a short, when I connect it to my pc, it does not turn on the fan turns a second and turns off and when I disconnect the pc it works correctly, with a multimeter I made measurements on the connectors of 6 and 8 pins and in some it gave me 15.04 and did not give a 'beep' as in the others, I made measurements the same in some mosfets and two of them showed similar values ​​to 15.04Are those mosfets short or can it be something else?(the red circles were where I measured those values)
GTX 780ti repair attempt - Page 1
Forum section: electronics / repair

author: dicky96
author_rank: Regular Contributor
timestamp: April 21, 2020, 11:35:34 am
content: Hi guysFirst let me just mention I have been posting about this on badcaps forum over the last couple of days, so apologies to anyone who also reads that forum. For anyone else all the details of what I have found so far are on this threadhttps://www.badcaps.net/forum/showthread.php?t=83970Seeing as we are on week six of lockdown in Spain, with the strictest restrictions in europe - I decided to try and learn to repair GPUs as it is something I want to do but have no experience. And now I have plenty of time on my hands. Soooooo....I have two GTX 780ti and one GTX 780 (that was supposed to be a 780ti but isn't) which I got off ebay spares or repair, and also a GTX 770 that I got some time ago at the local flea market for 2 euros.Of these four, I have a Palit 780ti and a Gainward Phantom 780 which look to be pretty much the same PCB, and a Gigabyte 780ti that is a different board design and looks rather similar to the GTX 770One of the guys on badcaps pointed me to a thread on herehttps://www.eevblog.com/forum/repair/nvidia-gtx-780-pcb-circuit-component-id/and it seems there are folks here who know about these cards so I thought i would ask hereBasically I haveGigabyte 780ti - shorts on both Vcore and VramGigabyte 770 - no shorts on Vcore or Vram but after powering on a few times one of the FETs sparked and a little bit of plastic blew off it! It also has 3 capacitors missing on the 12V supply.Palit GTX 780ti - short on Vram supply. I already removed the inductors to trace the fault and found one dual FET driving Vram was short to 12VGainward Phantom - no shorts on Vcore or Vram but I have no output from either Vcore or Vram VRMsAll the details are on badcaps, but basically I traced the lack of Vcore and Vram on the Phantom to the fact the PWM controller is not enabled. I then found I have a missing supply rail which, from the other thread posted here, I found that rail is PCI-e supply. Someone else has been 'messing' here so I had to clean up their rather untidy soldering. I found the controller RT8071 has 5V input, and no short on the output but the EN signal is low so it can't start. But where does the EN signal come from?That's as far as I have got with these - over to someone with more experience than me, which isn't difficult as my experience of GPU repair is like zero.See attached pics, they will explain this much clearer.cheers
GTX 970 Repair - Page 1
Forum section: electronics / repair

author: amiller112
author_rank: Newbie
timestamp: March 21, 2021, 10:06:28 pm
content: Hi, so I decided to buy some faulty graphics cards and have a go at fixing them. I decided to start with a cheap GTX 970.So far I have replaced a cracked current sense resistor and one 10uF ceramic cap. The issue I am now having is that all the voltage rails are ok, except for the RAM one.This should be around 1.5V and I'm getting 0V, the MOSFETS check out ok, but the controller chip really looks a bit dodgy.The problem is I have no idea what part this chip is, it only has '08 20 832' or '08 2G 832' it looks like it may have previously had rework attempted.From the pic it is U6 also Q12 looks a bit dodgy as well.Any ideas on the part number or an equivalent?Thanks

author: amiller112
author_rank: Newbie
timestamp: March 22, 2021, 11:20:51 am
content: I havent had time to fully check this post, but I may have found the info I was looking for.If only I had searched gtx970 and not gtx 970 XD.https://www.eevblog.com/forum/repair/msi-gtx970-4g-oc/msg3368136/#msg3368136

author: wraper
author_rank: Unknown
timestamp: March 22, 2021, 11:46:00 am
content: RT8809BZQW, can also use RT8809BGQW as it's the same.

author: amiller112
author_rank: Newbie
timestamp: March 22, 2021, 01:33:56 pm
content: Thanks, not 100% sure it's the issue yet, but having the datasheet helps a lot in diagnosing the issue.At the very least I'll now know where the enable and voltage pins are, and also what passives should connect where.
GTX 970 Repair - Page 1
Forum section: electronics / repair

author: konstan10
author_rank: Newbie
timestamp: April 06, 2020, 06:56:52 pm
content: Hi guys, I'm tryna fix my 970. When it's plugged in, fans spin but no image. I founded two fucked mosfets on the board as well as two missing capacitors, and an exposed trace. Is there anything else I should check for before I go on replacing things? Thank you in advance!https://imgur.com/a/oVk5Fns

author: Manul
author_rank: Super Contributor
timestamp: April 07, 2020, 01:42:51 am
content: Quote from: konstan10 on April 06, 2020, 06:56:52 pmYou should definetly check for shorted power rails. Because obviously something must have fucked these mosfets.I don't know about missing capacitors. How they got missing on your card? Maybe they are just not populated? Would be good to find schematic for reference.

author: JKKDev
author_rank: Regular Contributor
timestamp: April 07, 2020, 11:38:02 am
content: There are solder balls on the board. If you didn't cause them someone else was already trying to repair the gpu. Does it get recognized by the pc?

author: konstan10
author_rank: Newbie
timestamp: April 07, 2020, 04:20:39 pm
content: I'll be honest, I bought it off of ebay for a steal of a price, so if anything i'm not losing much in the end, i got nothing better to do anyways. The capacitors were there but barely hanging on...I just took them off with tweezers. Yeah and the mosfets were like that before I plugged the card in. I'll plug it in again later today and report back.

author: senso
author_rank: Frequent Contributor
timestamp: April 07, 2020, 04:45:12 pm
content: One of the missing caps is on one of the PCIe differential pair(last photo).At least two mosfets seem to have been replaced with an hot air gun, too much solder and too much heat(and/or too long).Missing SMD caps because the pads have extra solder, those are not DNP(do not place) footprints.Expect a dead core due to failed voltage regulators.
Guitar Footswitch Nuts - Page 1
Forum section: electronics / repair

author: paul_g_787
author_rank: Frequent Contributor
timestamp: November 03, 2019, 07:45:25 pm
content: Hi.I have a Vox VFS5 foot switch here and the silver buttons keep pushing through the chassis. It appears whoever replaced the nuts has used 12mm Nuts instead of 15/32" - 32 Thread.Vox appear not to be interested in helping as I have emailed them four times with not one reply.It seems that this is a common size for foot-switch nuts.It seems that mouser stock them but they want £12 delivery!https://www.mouser.co.uk/datasheet/2/215/458-741586.pdfCan anyone suggest a UK supplier who would probably stock nuts of this size?Thanks

author: floobydust
author_rank: Super Contributor
timestamp: November 03, 2019, 08:16:18 pm
content: Across the pond here but the foot switch likely made by Carling Technologies. That's a 1/2" 12.70mm panel cutout, 15/32-2A threaded shaft, and the9/16" hex nut 380-08602, and dress facenut 380-08810.Mouser UK has the 380-08602 in stock £0.21PS I'm using Loctite on both nuts.edit: oh, not availability but it's only the shipping costs? I can't help you with lowest S&H UK distributors.

author: paul_g_787
author_rank: Frequent Contributor
timestamp: November 06, 2019, 08:39:42 pm
content: Well I have been on to Carling technologies and they have informed me it is not one of their switches.
Guitar pedal with possible input jack ground issue - Page 1
Forum section: electronics / repair

author: d3vCr0w
author_rank: Contributor
timestamp: August 14, 2020, 04:41:29 pm
content: Hello people, hope you're all doing great. I'm in trouble with this guitar pedal, when I have the instrument plugged in and the pedal is not engaged, the bypass signal goes through and I can hear it, but when I engage it, all I can hear is a 'hum' noise. I took it apart and noticed that there's something wrong with the input jack, I somehow wiggle it and depending on whether it makes a ground contact with the case or not, the pedal works and I can hear the effect (how it's supposed to be), here's a short video explaining itand some pictureshttps://imgur.com/a/EG1OnTf.Can any of you help me figure out what's wrong with it? Thanks beforehand.

author: Buriedcode
author_rank: Super Contributor
timestamp: August 14, 2020, 05:59:26 pm
content: Well it sounds like you've already found the problem - the input jack.Most pedals I've worked on have a stereo input jack - so that when you plug a mono jack into the input it shorts the ring (connected to the battery negative) to the sleeve (which is ground) which turns on the pedal. The footswitch just switches between the effect and bypass.I suppose it could be a bad contact with the case as you stated, in which case a simple continuity test between thegreywire on the input jack and the inside of the case. It couldn't hurt to do the same on the output jack, because that doesn't have a sleeve/ground wire, because it is also in electrical contact with the case.Either way, with these things, it is often a mechanical failure - the switch, the connectors, or the knobs, things that move. The sockets generally take a bit of a beating, with regular use, and years of rough "stomps" that can hit the jack plug. I'd just replace both the sockets, they look to be fairly standard - just remember, you'll need one stereo, and one mono, although you could just use a stereo on the output, as you're only connecting one wire to the tip.

author: d3vCr0w
author_rank: Contributor
timestamp: August 14, 2020, 06:42:10 pm
content: Thanks for your reply Buriedcode!, I just checked with the multimeter and there is effectively continuity between the gray wire of the input jack with the case, and between the lifted tab of the output jack with the case.

author: Pete66
author_rank: Regular Contributor
timestamp: August 14, 2020, 07:38:48 pm
content: Does the LED light up when you turn the switch on?Are you running it on a battery or adapter?

author: d3vCr0w
author_rank: Contributor
timestamp: August 14, 2020, 08:01:16 pm
content: Yes, the LED turns on when I engage the pedal, and I tried both with a 9V battery and two different power supply adapters.
Gusmer H-2000 proportioning unit keeps blowing "Phase control" block - Page 1
Forum section: electronics / repair

author: ExtraThiccBoi
author_rank: Contributor
timestamp: February 29, 2020, 11:43:20 am
content: Hi,at our company (polyurethane foam etc.) we use Gusmer H-2000 proportioning units. They are very reliable, but one of them has repeatedly gone bad. The unit has a simple system for heating up the hoses with foam components. The system includes thermocouple temp reading + PID controller and hose current setting. On the bad unit, the first time we lost the hose heating, the "143PHC" thing has gone bad. It's a really well-potted cluster of components, I smashed the bad one into pieces, but unfortunately, I destroyed it so hard I couldn't reverse engineer it. There was a pot, SMD resistor, capacitor, a diode (maybe zener) and some 3-prong silicon device which I think was a triac. I managed to dig up some new old stock ones for sale and replaced it, but the hose heating died again. The only solution to make the heating work again is to bypass the SSR, but then, the current setting still doesn't work and the machine keeps tripping a breaker (it now operates in this kinda f.ed up mode because we need it to operate amap). If SSR is not bypassed, the whole system is dead. I include schematic and manual, hose heating system troubleshooting is on page 24. I don't have access to the machine at the moment, but I had a look at a similar one. I can post photos if needed. Please tell me what components to check/replace etc. The original analog temperature controller has been replaced with CAL 3200 PID.Pages in Parts identification brochure: 69-74Manual - hose heating troubleshooting: 24
GW Instek 8131H Frequency counter - Page 1
Forum section: electronics / repair

author: ruaidhri
author_rank: Newbie
timestamp: November 07, 2022, 12:08:13 pm
content: My 8131H frequency counter has stopped working. The display is blank but did work a week ago when it just showed 0. The 12V and 5V rails seem to be ok but no voltage can be found on the display circuit board. There is a 10MHz triangle wave at the crystal. I can't find a circuit diagram anywhere. Help!

author: UtahMikey
author_rank: Newbie
timestamp: November 07, 2022, 08:28:30 pm
content: Since we don't know about how it is built, look for cable or connectors to display. Trace 5V to display? Sounds like a connector pin or trace?Wiggle and check continuity on all connections to display.Go tohttps://www.gwinstek.com/en-global/products/detail/GFC-8270H_GFC-8131Hand tell support you need a schematics.You may have to email them many times to get attention and service help?You might post pictures so folks could think on it!Keep going, sounds like you found a major problem, lack of power to the display?Good Luck

author: coromonadalix
author_rank: Super Contributor
timestamp: November 08, 2022, 12:35:53 pm
content: open the case and show us photos ... and take notes of the main ic's in iti think they are based on intersil ic's ... if its the case there is many schematics on the web for them
GW Instek GDM-8135 Service Manual Needed - Page 1
Forum section: electronics / repair

author: Busta
author_rank: Newbie
timestamp: August 02, 2019, 11:32:27 pm
content: I recently bought a used GDM-8135 on EBAY. It only reads voltages on the 2 lowest ranges.Resistance is ok. Does anyone have a PDF of the service manual. There are no schematics in the owner's manual. Nothing obvious or burned upon inspection. Any help is much appreciated!

author: whipaway
author_rank: Contributor
timestamp: January 27, 2024, 01:05:08 am
content: Yes, I know that this is a super-old topic, but here is theGW Instek GDM-8135 Service Manual.Hope this helps the OP and anyone else in need of this info.

author: floobydust
author_rank: Super Contributor
timestamp: January 27, 2024, 02:38:44 am
content: GDM-8135 is 3-1/2 digits. You posted 8145.GDM-8145 is is 4-1/2 digits, same as Wavetek Meterman BDM40, using ICL7135.edit: thanks for posting the other service manual
GW Instek GDM - 8341 - Not working on lower ranges - Page 1
Forum section: electronics / repair

author: InTooDeep
author_rank: Newbie
timestamp: September 11, 2023, 01:41:04 pm
content: Hi All,I've got a GW Instek Bench Multimeter and stupidly forgot to wind down the voltage on the High Volt supply I was measuring below 1000V dc (I think it got about 1500V) and now the autorange function does not work and it display wrong results when I manually put it in the lower ranges ( 500 mV, 5V), when I manually put it in the 50V, 500V & 1000V range it still reads correctly.Does anyone know where to start looking to which component(s) are likely to have been fried (nothing obviously looks damaged on the PCB)?Looking near where the input wires go it hasa Panasonic TX2SA-L2-5Vquite a few Analogue devices ADG411BRa Toward AC38Any help would greatly appreciated!Kind regardsAlex
GW Instek GDS-2064 Repair help needed - Page 1
Forum section: electronics / repair

author: Yipyip
author_rank: Newbie
timestamp: November 14, 2022, 06:27:30 am
content: Hello,I have a GWinstek GDS-2064 Oscilloscope that has failed. The red standby light is on, when the power button is pressed it goes out but the green on light does not come on. The backlight of the display is on at full insensitivity.I have checked that all connectors are firm and plugged in.Does anyone have a schematic or suggest what may have failed.RegardsIan

author: whipaway
author_rank: Contributor
timestamp: March 22, 2024, 09:51:36 pm
content: PDF of the power supply.

author: Yipyip
author_rank: Newbie
timestamp: August 22, 2025, 03:29:26 am
content: Thanks for the schematic. I had given up on repairing the scope but now I will give it another go. Regards Ian
GW Instek GDS-2072A - no boot - Page 1
Forum section: electronics / repair

author: just_hobby
author_rank: Newbie
timestamp: November 05, 2022, 11:42:17 pm
content: Hi,I have GW Instek GDS-2072A for about 3 years.Today I had a chance to use it, but it didn't boot for meI haven't used it for about 6 month due to moving to another house.Where do I start with fixing it?Thanks

author: just_hobby
author_rank: Newbie
timestamp: November 06, 2022, 06:14:04 pm
content: All right, to bring it to life I had to update firmware in safe mode.QuoteThen I performed SPC Calibration and vertical Accuracy Calibration from the Utility section.

author: shakalnokturn
author_rank: Super Contributor
timestamp: November 06, 2022, 10:30:03 pm
content: It's funny how the GoodWill Instek scopes tend to get corrupt firmwares so easily.I once had an older model that had a bad firmware and if you look around it's almost common.
GW-Instek GDS-800 Service Manual  - Page 1
Forum section: electronics / repair

author: msraya
author_rank: Unknown
timestamp: June 08, 2017, 09:28:57 am
content: Hello!I have a problem with an Promax OD-581 with vertical chanel accuracy...This Oscilloscope is a clone of GW-Instek GDS-800 series...I Only need service manual in order to run the auto cal function that the instrument have.It uses a BNC in the rear panel to do the AUTOCAL.But Promax in Spain only do calibrate the instruments if I send It to them..So if someone have the Service Manual PDF and send it to me, I will thank You foreverRegardsManuel

author: Machlee
author_rank: Contributor
timestamp: October 17, 2024, 06:44:22 am
content: Hello!I need the same thing.

author: tatel
author_rank: Frequent Contributor
timestamp: October 19, 2024, 11:08:09 am
content: Quote from: msraya on June 08, 2017, 09:28:57 amYou could perhaps contact Promax, they were nice enough to send documentation about a power supply to me.https://www.eevblog.com/forum/testgear/(rebadged)-promax-fac-364b-power-supply/msg5561753/#msg5561753
GW Instek GOM 802 milliohm meter calibration procedure - Page 1
Forum section: electronics / repair

author: Machlee
author_rank: Contributor
timestamp: September 01, 2025, 04:14:13 am
content: Hi everyone!My GW Instek GOM 802 failed the test at the 30 mOhm limit.But I don't have a service manual. I ask for help if anyone has one.
GW INSTEK GOM 802 repair question, seeking help. - Page 1
Forum section: electronics / repair

author: Paceguy
author_rank: Regular Contributor
timestamp: December 04, 2022, 06:58:08 pm
content: Hi everyoneI picked up this GW Instek GOM 802 milliohm meter some years back. A reject tag attached to it says unstable on low range. I plugged it in and there is fluctuation on low ohm readings. Does anyone know where I can find the service manual ? I found the operation manual on line, but there is no service info in it . Even a schematic diagram would be of help. I suspect that it's a filter cap problem but want to know what the supply rail voltages are suppose to be and where the test points are.Thanks in advance !

author: Paceguy
author_rank: Regular Contributor
timestamp: December 29, 2022, 03:27:53 pm
content: I checked the ESR of all the electro caps and all tested good. I observed that on some scales it displays OL, on others scales, I can make measurements, this all done with 4 wire / K.clips. I'm starting to think that it's something with the input section. Any ideas or service info would be much appreciated.

author: Ugur
author_rank: Regular Contributor
timestamp: December 30, 2022, 06:37:00 am
content: Take your multimeter to the amper stage and connect it to the source + and - section,do you read a constant current in all stages?At the lowest measuring range, you will need to measure 1A.You will need to read values such as 100mA, 10mA, 1mA in other stages.LTC1052 may be faulty!

author: Paceguy
author_rank: Regular Contributor
timestamp: January 03, 2023, 07:56:10 pm
content: Thanks, I will try that
GW Instek GOS-6112 Power Transformer Repair - Page 1
Forum section: electronics / repair

author: 4s6tmp
author_rank: Newbie
timestamp: January 15, 2021, 06:21:24 pm
content: Hi all,My GOS-6112 went kaput due to a power surge. The 230V 400mA fuse, MOV, and finally the Transformer Primary were blown. I was reluctant to rewind it as it would almost cost me the price of the entire scope. Thus I was looking for a replacement transformer.At last, I wrote to GW Instek Taiwan. After some back and forth emails, they sent me this datasheet of this Transformer P/N GOS-6103-PT .https://drive.google.com/file/d/1D93kymphGQkTa4NEuIaPETEYmKxPj2W_/view?usp=sharingThe 0V Primary tap is an open circuit in my transformer. I am now hopeful that it could be this thermal fuse that has been blown.Have you ever ripped off a GOS-6103-PT? Is the thermal fuse eacily accessible? This seems to have been soaked in Shellac. Feels very rigid and strong.

author: fourtytwo42
author_rank: Super Contributor
timestamp: January 15, 2021, 08:32:15 pm
content: I have had thermal fuses open from current surges but that's a very expensive custom trafo so if your gonna do the job be EXTREMELY careful, I saw a post recently where some fool tried to open a trafo by slashing it with a knife and completely destroyed it! Think of it as open heart surgery!It's most likely on the side with the primary wires. On that side very carefully peel back the copper (remember it has to be resoldered afterwards, then each layer of insulation (WITHOUT CUTTING ANY WINDING WIRES UNDER IT) cutting alternate sides so the cuts wont overlap when it is re-assembled. Keep following that 0V lead and if you are lucky you will find it jointed to a bare wire or something other than winding wire, that will be a lead of the cutout. Hopefully you can gently prise the cutout out of its enfolding layers of insulation and replace it (dont be tempted to just short it out).Good luck

author: nctnico
author_rank: Super Contributor
timestamp: January 16, 2021, 03:14:54 am
content: If you look at the pictures you'll see the primary windings seem to be under the secondary windings making it impossible to get to the thermal fuse. I'd use the working primary windings (perhaps add a 230V to 115V transformer if necessary).
GW Instek GOS-6200 Inten Control not working - Page 1
Forum section: electronics / repair

author: Masud
author_rank: Newbie
timestamp: April 24, 2020, 09:11:46 am
content: Salam All Master..Any One Help me...I have a problem..Oscilloscope GW Instek GOS 6200 Inten setting panel not working,and Contras very High and can't be set with knop panel...and there are image issue..Can any One help me ...where first i ceck for componen problem..thanks....note..on Red arrow...sinyal can effect if front panel knop setting change..0-6V..

author: coromonadalix
author_rank: Super Contributor
timestamp: April 24, 2020, 05:17:06 pm
content: service manualcheck u554 on page 18, its an tlo82, it goes to the j803 connector on page 24 this connector has the intensity signal ..on page 35, are your front panel controls are working correctly ?You have to follow completly the intensity signal path, check all voltages ... not assume the red arrow point out the problem ? if you say it varies from 0 to 6 volts, i cant say its correct since i dont have a complete schematic.Print out all the pages and tape them together to have an good idea of the circuit(S) but they seem to be wrongly scanned, they miss a central section ??Send an email to gw instek, maybe they could send you an service manual ??

author: coromonadalix
author_rank: Super Contributor
timestamp: April 25, 2020, 03:34:28 pm
content: Sorry if you wrote to meI dont want to be rude BUTI wont help you modify your scope.If you dont have any electonical knowledge, i wont take the chance, nor being help responsible if you do mistake(s).Your scope has been designed in a way, it should work as intended, if not, you have to find the cause without adding modifications, and know how to use some instruments to do it.The schematics are incomplete(s), and can create miss-interpretations
GW Instek GPD-3303S error firmware. Help me please! - Page 1
Forum section: electronics / repair

author: uoemx
author_rank: Contributor
timestamp: September 19, 2023, 03:39:02 pm
content: My GW instek GPD-3303S power supply has the following error:When I load the program for the pic18f85J10 using the ISP port of the t48 (tl866-3G) loader, the power supply jumps in random numbers. I removed the 93c66 memory ic and cleared it, the power supply showed a relatively standard voltage and the current error was about 100mA. After that, when I went into calibration, the power supply no longer displayed the correct current but had a very large error.But the external current meter displays correctly, only the display on the power supply jumps wildly.At that time, I deleted the memory of ic 93c66 and the device displayed the correct voltage, but the current error was about 100mA. I updated firmware to ver 2.9 and 2.11 but it didn't work. I cannot access it by command via MTTY because the power supply is not responding. I suspect the firmware has errors in both the PIC18F85J10 mcu and the 93C66 memory ic. So, if you own this power supply, please help me read the firmware program.2 First picture without calibrating the power supply.The next 2 pictures are the power supply after calibrationThe last 2 pictures when calibrating but re-measuring amps with Fluke 179Here is the firmware I read from my GW instek GPD-3303S power supplyhttps://www.mediafire.com/folder/00ztfjvaucbtc/2If I have to repair hardware, which part should I check because I have repaired it a few times beforeSorry my English is so badThank you very much!

author: uoemx
author_rank: Contributor
timestamp: September 23, 2023, 10:34:18 am
content: Here is the schematic:https://www.mediafire.com/file/5ktdrde0p6b0ucs/GPD3303SM.pdf/file
GW Instek GPD-3303D Dumpster Diving Fix - Page 1
Forum section: electronics / repair

author: AlMuz
author_rank: Newbie
timestamp: July 18, 2022, 12:57:55 am
content: One of the perks visiting office these days was an opportunity to grab a split-rail PSU which was destined to the dumpster.The symptoms:On power up you can hear some relays clickYou also can hear the buzz of toroidal transformerScreen and buttons did not workScreen and buttons could occasionally turn on (e.g. after smacking or shaking the unit) and then randomly turn off a second or two laterWhen screen was on - device was functional, I could enable PSU outputs which stayed active even after screen went back offI could enable outputs with the screen OFF by holding output button and smacking/shaking the unit, but could not see a voltage/current settingObviously something was wrong with control panel and more likely its power supply circuitry (likely loose contact somewhere).Taking the cover off was relatively quick, but the control panel itself is a dual PCB sandwich connected with pin-headers and held up by terminals:So I had to remove all terminals to take the panel apparat completely:This allowed to trace power supply circuit to the panel components:The control panel is supplied by AC input from transformer (4-grey wires connecting to the top of the control panel).After rectifier there are two LDOs in parallel:3V3 to supply a PIC microcontroller - the brain of this PSU5V with 2x 1N4004 in series on its outputThis second circuitry produces approx. 3.5V to the front board, which is used to light up buttons and 7-segment LEDs.The problem was that one of these 1N4004 diodes was glitchy. Its internal contacts were loose.So depending on surrounding temperature or vibrations 1N4004 was either working or it was a broken circuit.Just tapping on it or bending the pin turned the PSU panel ON.https://youtu.be/yT6edyKEJuoEventually I ended up replacing 1N4004 as a quickest fix, but if it will ever break again I will replace diodes with a small buck converter module

author: coromonadalix
author_rank: Super Contributor
timestamp: July 18, 2022, 12:15:26 pm
content: Always better with an manual lollthe second link is too big to host herehttps://fabacademy.org/2019/labs/kochi/students/jofin-thomas/Downloads/power.pdfhttp://www.eltest.hu/pdf/GPD3303SM.pdf