hybridfree/eevblog-posts huggingface dataset:
HELP Textronix TDS5032 Driver does not appear, after several times it hangs - Page 1
Forum section: electronics / repair

author: Wahyueko
author_rank: Contributor
timestamp: July 20, 2022, 04:06:45 pm
content: At first, I tried to change the IDE HDD to SSD by converting SATA to IDE. by cloning the built-in 40GB HDD to a 120GB SSDthen I tried to change the default Celeron 2.0Ghz processor, I replaced the Intel Pentium 4 2.8Ghz.Then I tried to turn on the normal start, as usual, then after using it for a long time it suddenly hangs, and gets stuck, I restart it by pressing the power button, then it can still turn on normally.in the future, I try to turn it on again at the beginning of the start it suddenly hangs, and BSOD there is a message like the attachment picture "*** STOP: 0x0000009C (0x000.........)"after the crash, it reboots itself, when opening the TekScope application it immediately Errors. the front panel light is off.After I checked in the device manager, it turned out that the Tektronix and Acquisition Drivers did not appear.I've tried some troubleshooting from docs 071-1004-02.I've checked the power supply voltage, and I checked everything is safe.and check the voltage on the J1800 Acq Board it's also safe for all the voltages.I've tried reinstalling the Tekscope software from versions 1.2.1 and 1.1.5 and to no avail.I reinstalled all motherboard drivers too, but still no luck.When I try to reinstall the chipset driver. when installing at 90% of the front panel lights were on and off again.Please help what should I check again or maybe there is a hardware problem?

author: coromonadalix
author_rank: Super Contributor
timestamp: July 20, 2022, 09:32:34 pm
content: may help ?http://windowsbulletin.com/how-to-fix-bsod-stop-error-0x0000009c/not being rude, but you should revert back all hardwares changes, since you seem to have "played a little" ... and try to bring back some functionality as a pc at firstIt refer to an hardware problemcheck you device error pid$vid in the device properties

author: Wahyueko
author_rank: Contributor
timestamp: July 21, 2022, 03:43:52 pm
content: Thanks for reply,ill do that but now in device manager the driver not appear

author: coromonadalix
author_rank: Super Contributor
timestamp: July 21, 2022, 04:34:30 pm
content: The error you mean ?

author: Wahyueko
author_rank: Contributor
timestamp: July 21, 2022, 06:28:51 pm
content: I have returned the HDD and processor, but the Tektronix driver still doesn't appear.Is it possible that the tek hardware is faulty? or the motherboard?

author: Wahyueko
author_rank: Contributor
timestamp: July 26, 2022, 06:20:14 pm
content: Its mean hardware damage?

author: Wahyueko
author_rank: Contributor
timestamp: August 01, 2022, 10:35:59 pm
content: Help me , if anyone have downloadable IMAGE ISO system restore TDS5032 I will buy it.
Help to find this pwm controller - Page 1
Forum section: electronics / repair

author: wawinfo
author_rank: Contributor
timestamp: November 13, 2023, 12:23:09 pm
content: Can someone help me find the correct part number or at least similar datasheet?The code written on chip is "1F2=C1Z"

author: wraper
author_rank: Unknown
timestamp: November 13, 2023, 12:40:58 pm
content: R7732LGEhttps://www.richtek.com/assets/product_file/R7732/R7732-01.pdfActual device code is IF2= (page 2)

author: fzabkar
author_rank: Super Contributor
timestamp: November 13, 2023, 04:12:49 pm
content: I think the code is F2=. The leading marking appears to be a vertical line.http://markingcodes.com/search/c/f2%3D

author: wraper
author_rank: Unknown
timestamp: November 13, 2023, 04:48:11 pm
content: Quote from: fzabkar on November 13, 2023, 04:12:49 pmIt's a vertical bar but it's actually a part of a part number marking, and R7732LGE actually has |F2=marking which is a bit unusual for Richtek as in 99% of cases their ICs have 3 or 2 symbol marking. F2= that website shows for it is incorrect. Neither Richtek puts vertical lines on their ICs to mark orientation, they put a small triangle in the corner of pin 1.

author: fzabkar
author_rank: Super Contributor
timestamp: November 13, 2023, 05:00:42 pm
content: Quote from: wraper on November 13, 2023, 04:48:11 pmRichtek's own documentation is confusing.This photo of an R7731AGE has a vertical line (|DP=):https://ae01.alicdn.com/kf/Hb52f2df9b55b4f0199511cedf37a0c18O/5-R7731AGE-R7731AG-R7731A-R7731-DP-IDP-SOT-23-6.jpgThis document assigns a product code of "DP=" to the IC:https://www.rom.by/files/Richtek_Marking_Code.PDFThe datasheet, however, states that "IDP= : Product Code":https://file.elecfans.com/web2/M00/05/54/pYYBAGDezJGAG4dsAAWHhTHwRhk477.pdf

author: t1d
author_rank: Super Contributor
timestamp: November 16, 2023, 01:34:26 am
content: Are you sure the part is defective? It sure looks like a bad solder joint on the top left pin, as oriented in the picture. Maybe re-solder (aka "reflow") all of the pins? HTH.
Help to ID component - Page 1
Forum section: electronics / repair

author: ceehoppy1st
author_rank: Newbie
timestamp: August 23, 2024, 02:18:23 am
content: Good day,I'm asking help to identify a fried component. This board is a controller for an automotive (school bus) exterior video camera system. Sold by Rosco Vision in the US as Safe-T-Scope 360, the board is "omniVUE" made by image-Next in South Korea (now named Beyond_i).The board has no power or signal outputs (ie, mostly dead). It looks to have gotten some water on it - some corrosion here and there and it has blown the ass out of some kind of power IC?. The component U2 has "ACB4UB" on it. Unable to find a datasheet on it (sigh- my Google-foo is weak)The controller is made of unobtainium. It's only a year or two old but the bus dealer and Rosco say that they can't get enough new parts to supply new bus manufacturing, so forget about service replacements.So any help figuring out what this part is would be appreciated.thanks

author: Kim Christensen
author_rank: Super Contributor
timestamp: August 23, 2024, 02:33:21 am
content: Looks like it might be a SY8083PFCC DC-DC converter IC. As per the datasheet attached:Top Mark: ACBxyz (device code: ACB, x=year code, y=week code, z= lot number code
Help to ID smd diode - Page 1
Forum section: electronics / repair

author: cozza
author_rank: Regular Contributor
timestamp: November 11, 2021, 11:10:51 pm
content: Hi I have a few dali LED ballasts to repair, in all units the diode / TVS has failed shorted and blown the series 4.7k resistor.I don't recognise the logo unfortunately - can anyone help ID this diode / TVS?Initially I thought from the DK marking it might be be an SMBJ60A uni-directional 60V TVS, but that does not make sense in the circuit.The resistor connects to HV + and the anode of the diode to HV +. The common point connects to an HV startup / line voltge sense pin on the IC, HVLED001A.I've measured a working unit and there is up to 314V DC across this part - ruling out the 60V TVS part. It's not part of the application note for the IC, looks like a blocking diode.Any help appreciated

author: abdulbadii
author_rank: Frequent Contributor
timestamp: November 11, 2021, 11:36:54 pm
content: cross check ?https://www.mouser.com/c/?q=transilhttps://www.digikey.com/en/products/filter/tvs-diodes/144?s=N4IgTCBcDaIC4CcCGA7AzgSwDYgLoF8ghttps://octopart.com/search?q=transil&currency=USD&specs=0

author: cozza
author_rank: Regular Contributor
timestamp: November 13, 2021, 03:24:44 am
content: Thanks, but that's not really helpful.I can't find a substitute for it if I don't know the specs yet.It could be a diode or a transil.

author: fzabkar
author_rank: Super Contributor
timestamp: November 13, 2021, 05:20:08 am
content: Can you tell us the date codes on the other parts? I'm thinking that "09" is a date code, but I'd like to be more confident.

author: cozza
author_rank: Regular Contributor
timestamp: November 14, 2021, 07:47:05 pm
content: Hi Fzabkar. A few of the ICs have a 2018 date code, the QC stickers on the ballast indicate week 48/ 2019.Thank you!

author: cozza
author_rank: Regular Contributor
timestamp: November 24, 2021, 12:51:47 am
content: Hi I'm bumping this request again. Can anyone ID the manufacturer's logo on the device?Searching semi manufacturer logo lists has so far turned up no match for me

author: maxwelllls
author_rank: Contributor
timestamp: December 02, 2021, 05:59:31 am
content: Quote from: cozza on November 13, 2021, 03:24:44 amDK mark,maybe is a 14V zener diodes,MMSZ4701
Help to identify a part - Page 1
Forum section: electronics / repair

author: higginsdj
author_rank: Contributor
timestamp: May 30, 2025, 12:38:42 pm
content: Hi all,I need help identifying a part type and where to buy them. The red socket in the attached image JP12. Although there are 12 holes there are only 6 pins (staggered)CheersDavid

author: AndyC_772
author_rank: Super Contributor
timestamp: May 30, 2025, 12:42:44 pm
content: https://www.mouser.co.uk/c/connectors/headers-wire-housings/?m=Wurth%20Elektronik&series=WR-MMWurth Electronics WR-MM series
Help to identify a Sensata thermal switch - Page 1
Forum section: electronics / repair

author: gkmaia
author_rank: Frequent Contributor
timestamp: January 17, 2021, 06:13:42 am
content: looking for some help to identify a thermostatic switch.I got two to identify but the issue is I cannot make sense of the temperature comparing the markings to the chart on the datasheet.They are part of a spa pool heater. I would like to know the temperature rating so I can test if they are within spec.One is a manual and the other is automatic. The numbers marked go as bellow.1NT12L-2449 L50-MR 99371NT01L-2972 L51-12 9937Datasheet bellowhttps://www.sensata.com/sites/default/files/a/sensata-1nt%20series-fixed%20temperature%20thermostats-datasheet.pdf

author: fzabkar
author_rank: Super Contributor
timestamp: January 17, 2021, 07:21:14 pm
content: ISTM that the temperature specs are buried within the "2449" and "2972" suffixes. I suspect that "9937" is a YYWW date code.

author: Niklas
author_rank: Frequent Contributor
timestamp: January 17, 2021, 11:24:31 pm
content: 50'C with manual reset and 51'C with -12'C (below 51'C) for automatic reset.
Help to identify burnt mosfet - Page 1
Forum section: electronics / repair

author: Mokko
author_rank: Newbie
timestamp: December 11, 2023, 09:20:27 am
content: Hello!I was wondering if anyone could help me identify this mosfet?I think it says "KJUNO" on top row "5" in the center followed by an explosion and "9A322" on the bottom row.Best regards from Sweden!

author: magic
author_rank: Super Contributor
timestamp: December 11, 2023, 10:10:17 am
content: I think it's K1?N0, maybe K14N0, but still nothing

author: Mechatrommer
author_rank: Super Contributor
timestamp: December 11, 2023, 10:26:36 am
content: https://www.datasheetcatalog.com/datasheets_pdf/K/1/4/N/K14N04FM.shtmlhttps://pdf.datasheetcatalog.com/datasheet/SGSThomsonMicroelectronics/mXryxxq.pdfhttps://www.alldatasheet.com/view.jsp?Searchword=K14N0&sField=1https://pdf1.alldatasheet.com/datasheet-pdf/download/25653/STMICROELECTRONICS/VNK14N04FM.html

author: Mokko
author_rank: Newbie
timestamp: December 11, 2023, 12:52:27 pm
content: Wow thank you guys!Now i just need to find something to replace it with, doesn't look easy to find something similar, how important is it to get about the same values? It is mounted on a PCB that powers the lights in the interior on an old car.

author: fzabkar
author_rank: Super Contributor
timestamp: December 11, 2023, 02:43:42 pm
content: STK14N05?https://alltransistors.com/adv/pdfdatasheet_st/stk14n05_stk14n06.pdf

author: magic
author_rank: Super Contributor
timestamp: December 11, 2023, 04:41:51 pm
content: Maybe.I just noticed that there is a third line of text in the middle, which seems to start with 5.

author: fzabkar
author_rank: Super Contributor
timestamp: December 11, 2023, 04:55:13 pm
content: https://ersatzteilcenter.net/media/image/product/94/lg/k14n05.jpg
Help to identify IEE VFD display driver - Page 1
Forum section: electronics / repair

author: artelse
author_rank: Regular Contributor
timestamp: December 26, 2023, 12:02:42 am
content: I have this large IEE VFD display that I want to repair.Some VFD driver chips are dead and am trying to find out what they are and what make these are. The type number is 44791-01 and manufacturer logo is a 2 in a segmented circle see attached photo.A quick drawing of the connections:+---u---+d | | dd | | dd | || ||-- |V+ | \-- | Gnd| | dd | | dd | | d+-------+44791-01d = segment driverAny ideas, have not been able to find a datasheet.

author: coromonadalix
author_rank: Super Contributor
timestamp: December 26, 2023, 12:22:57 am
content: normally theses have discontinued for a long timeSUPERTEX 44791

author: fzabkar
author_rank: Super Contributor
timestamp: December 26, 2023, 02:13:33 am
content: Not the same but ...https://www.futurel.bg/datasheets/4/HV6810.pdf

author: artelse
author_rank: Regular Contributor
timestamp: December 26, 2023, 10:28:22 am
content: Thanks for the info, digging in some more on the HV6810 reference, I've found the Allegro Micro UCN5810 a predecessor of the HV6810 carries the 2 encircled logo on some chips. And double checking layout it seems pin compatible with the 44791.Cool, will order some from China, are cheap as well.

author: fzabkar
author_rank: Super Contributor
timestamp: December 26, 2023, 05:54:56 pm
content: The A6810xA appears to be a newer option:https://www.allegromicro.com/-/media/files/datasheets/a6810ep-datasheet.pdf(A6810xA, A6810xLW, A6810xEP)https://www.allegromicro.com/-/media/files/datasheets/a6810-datasheet.pdf(A6810)https://www.allegromicro.com/-/media/files/datasheets/ucn5810-datasheet.ashx(UCN5810)
Help to Identify MEMS Microphone Part Number - Page 1
Forum section: electronics / repair

author: Nyx_
author_rank: Newbie
timestamp: March 20, 2024, 07:50:39 pm
content: Hi Folks, Good day.I hope you all are doing good.I have a Headset (Jabra Evolve2 85) with some SMD microphones that stopped working due to a water contact...I'd like to replace those mics, however, I'm not sure what part number to order.I attached here few pictures of the devices. It's basically two types, I took multiple picture hoping it will help to identify the PartNumbers.I appreciate if anyone can help with this or any instruction on how to search for it.Thank a lot Folks.

author: selcuk
author_rank: Frequent Contributor
timestamp: March 20, 2024, 09:26:53 pm
content: I don't know the exact part number but it is similar to this company's products:https://www.knowles.com/docs/default-source/default-document-library/spm0687lr5h-1_winfrey_datasheet.pdf
Help to identify specs of diodes HS2-6 and H961 - Page 1
Forum section: electronics / repair

author: gkmaia
author_rank: Frequent Contributor
timestamp: November 25, 2019, 02:46:41 am
content: I am fixing a circuit that has some faulty diodes on the EHT circuit.Struggling to find the specs to replace HS2-6 and H961 as I am not sure what are their specs and they seem to be quite old.Anyone out there with some knowledge on vintage gear that could help wit the specs?

author: fzabkar
author_rank: Super Contributor
timestamp: November 25, 2019, 03:59:43 am
content: Can you identify the package? Do you have a circuit diagram?
Help to repair Agilent infinum 54855DSO oscilloscope power issue - Page 1
Forum section: electronics / repair

author: 999masks
author_rank: Newbie
timestamp: February 24, 2024, 12:03:19 am
content: if you guys can give me any suggestions i will appreciate it.I have Agilent infinum 54855DSO which i accidentally shorted at the ATX connector side that goes to Motherboard, i belive one of the 12V output while it was unpluged from MB.after that the oscilloscope stopped powering on. Mine has Celestica 5100 power supply with 4 power modules.The current issue:if i remove the connector(i think it caries some sensing signals, see below more detail) from power supply that goes to analog power generation board and plug the power cord,it will power on and boots. At this state I measured all thevoltages from power supply which looks good. As soon as iconnect that plug (this is not a power cable , I assume some sensig signal) it wont turn on. Imeasured the voltages from those wires, basically the powersupply has 4 different power modules. 2x3.3V 1x5V and-12 ,0, 12V the connector that i was referring, carries the samevoltages as their output at ATX connector (maybe POWERGOOD signal?) basically from that plug if i remove the pinthat connects to -12,0 +12v =24v (any side) the oscilloscopewill power on and boots. At this state the neither powerbutton or any button works on the front panel. I am askingif you can help me to troubleshoot or provide the modelschematic or similar. thanks in advance
Help to repair ISO-TECH IPS2303DD - Page 1
Forum section: electronics / repair

author: BobWells
author_rank: Newbie
timestamp: August 07, 2025, 07:53:57 pm
content: Hi all, hope you can help.Iv'e got a problem with the above bench power supply, I'll try to explain.The CC LED's are on with the amps knob at minimum with no load, turn them up about eight of a turn and they go out, no matter what voltage is set, also when I hook up a load, the voltage stays on whatever its set at, but nothing output, this is the same on both channels.I think I may have overloaded it in serial mode.I can't find a service manual or schematic, but if someone can point me to the area I should be investigating that would be a great help, or if someone has had this problem and repaired it, that would be fantastic.Thanks in advance, Bob

author: picburner
author_rank: Frequent Contributor
timestamp: August 08, 2025, 05:39:46 am
content: Your power supply should be a rebranded GW-Instek GPC-3030D, if so you can find the schematichere.

author: Gyro
author_rank: Super Contributor
timestamp: August 08, 2025, 08:35:22 am
content: Has the PSU evernotdone this? It is perfectly normal for the supply to dispay CC mode indication when the current is set to zero (and the voltage set to non-zero), otherwise there wouldn't be a smooth transition when it it set to limit at low currents.I don't understand what you mean by "also when I hook up a load, the voltage stays on whatever its set at, but nothing output", maybe you could clarify what you mean.The same behavior on both channels makes it being an actual fault less likely.

author: Sorama
author_rank: Frequent Contributor
timestamp: August 08, 2025, 10:08:53 am
content: Quote from: BobWells on August 07, 2025, 07:53:57 pmThat is expected behaviour and completely normal.Although some PS probably disconnect internally when there is no current flowing.

author: BobWells
author_rank: Newbie
timestamp: August 08, 2025, 03:14:35 pm
content: Hi Chris, thanks for your help.Regards the CC, its a bit difficult to explain, to set the CC I short the leads but there is no reading on the readout.Thanks Bob

author: BobWells
author_rank: Newbie
timestamp: August 10, 2025, 07:13:01 pm
content: Hello all, me again.Made some more tests and I decided to calibrate the unit (I have the data to do that) and when it came to setting the current at full limit (3A) it read 3A on the unit but nothing on the meter I was testing with (Fluke 87V).I'm gradually going through checking components and voltages, but nothing as yet.TBH I'm not sure which board I should be looking at as I don't havee a schematic.Any ideas / help would be much appreciated, Bob

author: Mr Lurpak
author_rank: Contributor
timestamp: October 13, 2025, 11:20:24 am
content: BTW, on different note yet same.IF you have one of these or Tektronix PS280/283 and your slave channel is not adjustable and output in the region of 30+ volts and have tried everything else. Try looking at the RELAYS on the power output board in front panelI gladly share this after weeks of frustration and ready to throw it out the window. Hope it will help someone else.
Help to turn on the Tektronix THS3014 Scope - Page 1
Forum section: electronics / repair

author: Wahyueko
author_rank: Contributor
timestamp: December 29, 2022, 06:23:53 pm
content: Please help, here I have a Tektronix THS3014, I bought it from a local online site in my country, but the unit is without Adapter/Charger and battery included.I tried turning it on by plugging in the supply voltage from the Lab Bench Power Supply, using the appropriate voltage from the 18V Tektronix charger and my current was set to exactly 840mA.However, when I press the on the button once on the front panel, there is no reaction. I have tried pressing it for a few seconds but there is no response either. I see that no current is entering the scope.what I'm asking is whether to turn on this Scope you have to use the default charger?Or when turning on there must be a battery installed?Or is there another way to turn on this scope?Because I don't have both, the charger and the original battery.

author: abdulbadii
author_rank: Frequent Contributor
timestamp: December 30, 2022, 02:13:24 am
content: if it's ensured to be supplied with the specific rating demanded, 18V , etc, simply the device is faultyOpen it up, test any should-be connected line is connected by MM continuitycold solder join ie. not 100% firmed one is possible, the most fundamental rule:Every tool not 100% clean and clear out of any matter not supposed to be as its part, is subjected to be faultySo clean it up completely first place then test/check if it works, if persists bring the schematic and reference manualup here

author: Wahyueko
author_rank: Contributor
timestamp: January 01, 2023, 05:56:40 pm
content: Thankyou now fixed sir.
Help trace what the IC is connected to in a Gossen Metrahit X-TRA / Pro - Page 1
Forum section: electronics / repair

author: giosif
author_rank: Frequent Contributor
timestamp: December 14, 2020, 08:14:33 pm
content: Hi,Apologies for the duplicate, but I thought I'd ask this explicitly, in case people are not following my other Gossen repair thread: could someone with a Metrahit X-TRA or Pro be so kind to check where the traces for the two IC pins in the green rectangle are going?Thank you!

author: giosif
author_rank: Frequent Contributor
timestamp: December 18, 2020, 03:33:50 pm
content: Anyone, please?

author: Florian68
author_rank: Newbie
timestamp: December 18, 2020, 09:10:46 pm
content: Maybe it helps you

author: giosif
author_rank: Frequent Contributor
timestamp: December 18, 2020, 09:59:20 pm
content: Many thanks!Ok, so those two pins don't go to the customer ADC IC, but to the unpopulated section on the board (probably populated for a different model).
Help tracing out HV on Tranceiver - Page 1
Forum section: electronics / repair

author: Crambone
author_rank: Frequent Contributor
timestamp: April 05, 2023, 12:57:41 pm
content: Guys I have TRAM D201 Transceiver that I’m seeing a high voltage on Pin 6 of the Synthesizer. I should be seeing 2.3vdc at all times but I’m getting 11.5 volts all other PINS show correct voltage.I’ve attached a schematic and you will find the synthesizer board in the lower left with Pin 6 highlighted blue. Any advice and what might be causing this Higher Voltage would be appreciated.

author: Wallace Gasiewicz
author_rank: Super Contributor
timestamp: April 05, 2023, 01:23:40 pm
content: Looks to me that 11 V would be correct in Manual tune in USB in Receive

author: Crambone
author_rank: Frequent Contributor
timestamp: April 05, 2023, 01:52:24 pm
content: Nope here is the PIN voltage chart

author: vk6zgo
author_rank: Super Contributor
timestamp: April 05, 2023, 02:13:14 pm
content: Q103 turned on "hard" or short circuit between source & drain.

author: Crambone
author_rank: Frequent Contributor
timestamp: April 05, 2023, 03:25:24 pm
content: Thanks I will check Q103

author: Crambone
author_rank: Frequent Contributor
timestamp: April 05, 2023, 09:40:35 pm
content: Yup it was Q103.
Help troubleshooting 200N15N MOSFET - Page 1
Forum section: electronics / repair

author: delfin2003
author_rank: Newbie
timestamp: July 12, 2025, 04:14:38 am
content: Please, help. I need a repair advice. I was discharging two 6s batteries using a LiPo discharger that I bought on Amazon. Walked into the room a few minutes later to a burning smell. One of the dischargers was no longer working! I assume it is 200N15N MOSFET that is burned out, even though visually, everything looks OK. Now, there are two of these MOSFETS in the device.Here's how I tested the MOSFET:1. I removed these MOSFETS from the board using pliers. Put my finger on all three leads.2. Put multimeter in diode mode.3. Put a black on S, put a red on D. Reads "OL" for both MOSFETS (No continuity, meaning we are in OFF state. This is OK)4. Put a red on G for 1 sec, remove red from G, put red back on D. One of the MOSFETS starts reading 0.02v and slowly rising. The other one, however, reads 1.18 volts and rising. (Reproduceable multiple times)Is one of them bad?Please advise.

author: inse
author_rank: Super Contributor
timestamp: July 12, 2025, 07:47:37 am
content: Probably not as it is unknown what test voltage the multimeter applies.If it is not sufficient to fully cross the gate threshold, tolerances would allow difference in conductivity.Either charge the gate with a lab power supply to 10V or a 9V battery.Usually semiconductors turn into conductors when overloaded.

author: MathWizard
author_rank: Super Contributor
timestamp: July 13, 2025, 09:28:58 pm
content: In the datasheet, it says the gate-source threshold voltage can be upto 4V, some DMM's won't get that high, so it's hard to say.But if you have a 5V charger, or 9V battery, that should do for the same test, connect the charger/battery so that + is on the gate, and neg on the source. If you have resistors, you can make a test circuit too, to be even more sure.

author: delfin2003
author_rank: Newbie
timestamp: July 14, 2025, 11:37:41 pm
content: I do have a 9V battery. Could you elaborate more on the testing steps? What should I be looking for? I am using Brymen BM869s as my digital multimeter.
Help understand the Compressor circuit of a Yamaha MG166CX console. - Page 1
Forum section: electronics / repair

author: Yamin
author_rank: Frequent Contributor
timestamp: December 20, 2019, 09:07:01 pm
content: Hi everyone I was hoping that you could help decipher the workings of the compressor circuit of the Yamaha console. I have attached a pdf of the preamp board and a photo of the circuit of interest. Would greatly appreciated your help any further tips on what to read/research would be awesome.Thanks in advance.
Help: Vox Guitar Amplifier Seeks New Transformer to Make With The Beats - Page 1
Forum section: electronics / repair

author: kazzle101
author_rank: Contributor
timestamp: February 24, 2021, 10:14:18 am
content: HelloI've been 'given' an old Vox Supertwin amplifier made in the early 1980's to to see if it can be repaired.The transformer has failed, I can tell on account of the smoke that comes out when its plugged in. So I'm looking for a replacement transformer, and I don't normally do mains voltage stuff.On the circuit diagram the transformer output is shown as being 30V at 1A:https://www.korguk.com/voxcircuits/circuits/suprtwin.jpgSearching around I found this: Vigortronix VTX-126-050-215 Chassis Transformer 230V 50VA 15V+15V:https://www.rapidonline.com/Catalogue/Product/88-3931Am I right I thinking I can connect the outputs in series to get the required 30V?And is this the right transformer to get regarding power? - I worked out the needed VA by the following: 1A * 30V = 30VAThanksKarl.

author: paf
author_rank: Regular Contributor
timestamp: February 24, 2021, 11:30:34 am
content: Yes. It is a good replacement.

author: bob91343
author_rank: Super Contributor
timestamp: February 24, 2021, 10:03:06 pm
content: Remember to get the winding polarity correct or you won't get output.
Help wanted to identify an ic - Page 1
Forum section: electronics / repair

author: Aurgelme
author_rank: Contributor
timestamp: April 07, 2025, 02:58:30 pm
content: If anyone knows what kind of IC this is, I'd be very grateful

author: coromonadalix
author_rank: Super Contributor
timestamp: April 07, 2025, 03:22:53 pm
content: it would help to know where, what, how, in witch it is used, we dont have any crystal ball with no information from you
Help, what does this chip code represent - Page 1
Forum section: electronics / repair

author: daisizhou
author_rank: Super Contributor
timestamp: April 12, 2023, 02:57:01 pm
content: https://www.alldatasheet.com/datasheet-pdf/pdf/858934/DIALOG/DA9053.htmlThe chip manual information is on top,I want to know what the number 37 at the end of this DA9053 37 represents.If you know, please let me know. Thank you

author: inse
author_rank: Super Contributor
timestamp: April 12, 2023, 03:42:08 pm
content: 30.1Variants Ordering InformationDA9053 supports delivery of customised variants indicated by xx in the part number above, please contact your local Dialog Semiconductor office or representative to discuss requirements

author: fzabkar
author_rank: Super Contributor
timestamp: April 12, 2023, 04:38:44 pm
content: QuoteI expect that a customer could define the default startup voltages and power on sequence for their particular application. "37" would refer to a particular configuration. FWIW, that's the way that Active Semiconductor marks its PMICs.https://www.renesas.com/us/en/document/dst/da9053-datasheet
Help, what model is this component? Looks like a discharge tube - Page 1
Forum section: electronics / repair

author: daisizhou
author_rank: Super Contributor
timestamp: February 23, 2023, 09:28:32 am
content: Hello everyone。I came across a component that looks like a discharge tube,It looks like a diode, but I think it's more like a discharge tubeI didn't find its data, if you know the data or know the exact model please let me know, thanks

author: jonpaul
author_rank: Super Contributor
timestamp: February 23, 2023, 10:54:40 am
content: Teccor Transients Absorbing Zener TAZj

author: daisizhou
author_rank: Super Contributor
timestamp: February 23, 2023, 11:02:39 am
content: Can you know the exact model?

author: fzabkar
author_rank: Super Contributor
timestamp: February 23, 2023, 11:42:39 pm
content: What is the application?

author: daisizhou
author_rank: Super Contributor
timestamp: February 24, 2023, 01:07:52 am
content: They are at the input end of ECG lead line,These pipes sometimes conduct (100k-300k), but they are normal after heating, so I don't know whether the components are damaged or normal, so I want to know the exact model and query the parameters

author: fzabkar
author_rank: Super Contributor
timestamp: February 24, 2023, 01:45:13 am
content: As I understand it, the input protection is required to protect the instrument from the high voltages produced by a defibrillator.https://www.medteq.net/article/iec-60601-1-defibrillator-protection-design-testhttp://www.medteq.info/med/files/Image/defib/ECG.pngApparently, the relevant standard is IEC 60601-2-27:2005.Could these be bidirectional 860V devices (sidactor)? Or 86V devices?Here is a complete catalogue from 2004:https://web.archive.org/web/20040414135933/http://www.teccor.com/web/PDF%20Files/Telecom/Complete.pdfhttps://web.archive.org/web/20021209163418/http://teccor.com/web/menuitems/downloads/datasheets.htm#ds_sidactor

author: jonpaul
author_rank: Super Contributor
timestamp: February 24, 2023, 03:47:27 am
content: for sure Teccor trademark, the bidirectional Sidactor (TM) is a unique 4 layer protector ideal for,such use.A TAZ or gas gap cannot be used.In patient connected medical device like EKG, ECG, etc the liabilities, legal and compliance JP have,stick government requirements for the device design, manufacture and services.Any part replacement, substitution or modification generally invalidites the approvals.Consult your country's medical device regulationsJon

author: daisizhou
author_rank: Super Contributor
timestamp: February 24, 2023, 04:02:38 am
content: Ok, I understand. Thank you for your help

author: daisizhou
author_rank: Super Contributor
timestamp: February 24, 2023, 04:05:35 am
content: Ok,Thank you for your help

author: fzabkar
author_rank: Super Contributor
timestamp: February 24, 2023, 04:26:51 am
content: Quote from: jonpaul on February 24, 2023, 03:47:27 amhttps://www.medteq.net/article/iec-60601-1-defibrillator-protection-design-testQuoteI would have thought that a spark gap or MOV would be too slow. :-?
Help, where should the missing potentiometer be? - Page 1
Forum section: electronics / repair

author: daisizhou
author_rank: Super Contributor
timestamp: August 31, 2023, 01:36:47 pm
content: Hallo every one,When I was checking the PCB circuit board,I found a P4 potentiometer and a 150 ohm resistor missing from the schematic diagram. I don't know where the most suitable position is for it.If you know, please let me know. Thank you**************************************This is the working principle of this part of the circuit****************************************ECG curves are generated by the microprocessor based on data tables. The processor updates the 8-bit D/A-converter in IC1 (channel A), usually 500 times per second. IC-3 converts current to voltage, and IC-2 makes the signal bipolar. The amplitude is adjusted using P1, and the zero point is adjusted using P4.IC1 D/A-converter part B sets the reference level for the curve generator D/A-converter part A. Part B thus determines the amplitude of the stimulus signal.The DC value for maximum amplitude is read back by the microprocessor's 10-bit A/D-input El, and can therefore be adjusted precisely.The other half of IC2 is used for operating the high-level output or the ECG signal. The circuit has an amplification of 4 times.The signal is filtered for high frequency noise with F18 before it is conducted to contact J8. C3 ensures bandwidth limitation in IC2. D9 is over voltage protection.**

author: tooki
author_rank: Super Contributor
timestamp: August 31, 2023, 11:45:58 pm
content: Please share the entire service manual, since you clearly have it. Snippets of the schematic are nowhere near as useful as the whole thing.

author: Kim Christensen
author_rank: Super Contributor
timestamp: September 01, 2023, 12:15:17 am
content: It looks like the pot P4 might be in series with R4... Hard to tell exactly without seeing both sides of the PCB. Best to trace it and ring it out with an ohmmeter to verify. Looks like a later revision of the PCB, so the schematic you have is out of date.

author: floobydust
author_rank: Super Contributor
timestamp: September 01, 2023, 01:58:56 am
content: It's a METRON QA-45 Defibrillator and Transcutaneous Pacemaker Analyzer. Could not find decent schematics.

author: daisizhou
author_rank: Super Contributor
timestamp: September 01, 2023, 03:38:47 am
content: ok
Help, wierd remote control behaviour on McIntosh MX121 receiver. - Page 1
Forum section: electronics / repair

author: CHexclaim
author_rank: Regular Contributor
timestamp: July 25, 2023, 01:14:42 pm
content: Hello and as usual thank you for helping other people.I have on the bench a McIntosh MX121 that came in saying "the remote control is not working". Indeed, testing it aparently showed that except that it works well only when the unit is in standby and power on is pressed in the remote. The unit powers on ok but then, it responds to no other command from the remote.So, issues with the electronics on the IR receiver is unlikely. Maybe somthing regarding a difference between the power supply to the IR receiver between standby and operation.Anyhow, the unit inside is very complex, it is a A/V control center. So, having the service manual or schematic would make the job much straight forward and professional. I haven't been able to find this information yet. Can anyone help with the service manual, shcematic or tips on what can be wrong.Much appreciated, Carlos.Indeed, testing it

author: David_AVD
author_rank: Super Contributor
timestamp: July 25, 2023, 08:49:27 pm
content: It appears to have a SMPS for the standby (backup) power supply and a linear main power supply.It could be that the capacitors in the SMPS are on the way out and the increased current draw once it's powered up is causing more noise on the rail that supplies the micro / IR section.

author: CHexclaim
author_rank: Regular Contributor
timestamp: July 25, 2023, 09:11:52 pm
content: Thank you for your replySo the SMPS would power all the uP for display, IR, switching, etc, and for the signal electronics there would be a linear PS?There is a main big transformer and caps what look like linear regulators and there is an SMPS. I'm attaching pictures.There is also, at the back of the unit, a board with i/Os for control. And, the connector has a label IR in.CH

author: David_AVD
author_rank: Super Contributor
timestamp: July 25, 2023, 09:43:56 pm
content: Normally the standby power supply runs at least one of the micro-controllers and the IR sensor so it can switch the main transformer on from standby.The display is often partly powered from the standby and partly from the main power supply.The large transformer usually powers all of the analog circuitry, power amplifiers and other stuff like the DSP.

author: wasedadoc
author_rank: Super Contributor
timestamp: July 25, 2023, 11:13:42 pm
content: Quote from: CHexclaim on July 25, 2023, 09:11:52 pmSome equipment has provision for plugging in an external IR receiver £dongle" so that the main unit can be controlled in a cabinet with closed opaque doors or similar situations where only the dongle can see the remote control. See page 6 of the owner's manual available athttps://www.audioservicemanuals.com/m/mcintosh/mcintosh-mx/51107-mcintosh-mx-121-owners-manual
Help with 2004 Soft-Start Repair - Page 1
Forum section: electronics / repair

author: digimbyte
author_rank: Newbie
timestamp: February 05, 2020, 10:28:41 pm
content: Hello! I have an air conditioner from a now defunct Alpine AU from 2004 and we had some lightning damage to the main soft-startWhat was damaged was some sort of resistor and a Triacwhat they were specifically, are unknown.I looked at other soft start boards for washing machines and other high powered AC motor controllers but nothing has been obvious as to what is commonI have replaced the TRIAC with a TOP3 BTA26 600B and the resistor connects pin A1 to Ground. other schematics have this at 100 Ohms but I don't think this is ideal.I could be wrong but I figured I would ask before putting this back into my live AC Air conditionerthis board came from the following air unitEcoHomes.biz : The JS 7017 AH Non Ducted Single Split System Air Conditioner by AlpineI assume this board is still in circulation somewhere or can be replaced for cheapTLDR: Is this the correct resistor value and Triac pair viable? (picture attached)

author: TheMG
author_rank: Frequent Contributor
timestamp: February 07, 2020, 03:25:37 am
content: If I'm not mistaking, the resistor is there to prevent leakage current from the opto from inadvertently triggering the TRIAC. A pull-down resistor effectively. 100 ohms seems like a reasonable value for this purpose.
Help with a Episode EA-AMP-8D-70A 8 Channel 70 Watt Amplifier. - Page 1
Forum section: electronics / repair

author: rfengg
author_rank: Regular Contributor
timestamp: September 18, 2023, 02:22:13 pm
content: Hi All,Need your advice on a Episode EA-AMP-8D-70A that I picked up at a garage sale during the weekend. The owner told me that it was broken and sure enough when I switched it on, there is a weird combination of LED's lighting up on the front panel.I am yet to open the unit up but understand that the 8 channel amp consists of 4 modules and each module has 2 channels each.What I am baffled by the LED status (pic attached) on the front panel which shows.....LED 1 in a pink colorLED 2 in redLED's 3,4,5 in blueLED's 6 and 8 in redLED 7 in pinkThe manual says that "RED LED – Amplifier is ON and is not functioning properly"......I can understand that.....but the pink color (which means RED and BLUE are ON at the same time)Does anyone have a schematic or service manual for these amps? Any pointers to amps with similar circuitry would be great as well.Have a good one.
Help with a header connector Please - Page 1
Forum section: electronics / repair

author: daveyk
author_rank: Frequent Contributor
timestamp: February 10, 2022, 07:08:14 pm
content: Please see this attachment if it doesn't show up in the message.I can find a 9 pin header at Allied Electronics and bought a number of them. I then remove every other pin.The problem is, the holes in the header pins (like in this picture) are about half again larger than the standard header pin opening.An IC does not plug in the header. It is used to raise a battery connector about 3.5-4mm off the PCB.It looks just like regular header otherwise.

author: abdulbadii
author_rank: Frequent Contributor
timestamp: February 12, 2022, 02:03:41 pm
content: from different country, different standard size?

author: MarkF
author_rank: Super Contributor
timestamp: February 12, 2022, 03:07:03 pm
content: Are you looking for something like this except having a pin pitch of 0.2" instead of the 0.1" in your picture?These accept a standard square header pin.These, shown above, can be had at Mouser (having 0.1" pitch):https://www.mouser.com/ProductDetail/3M-Electronic-Solutions-Division/929850-01-09-RA?qs=sGAEpiMZZMsvbV9l%252Bnr01PihptEZ55V2I don't know of ones with a 0.2" pitch.

author: tooki
author_rank: Super Contributor
timestamp: February 12, 2022, 11:12:40 pm
content: Quote from: daveyk on February 10, 2022, 07:08:14 pmMachined headers are available in a variety of different pin sizes (for both male and female ends) and you have to choose the right one for your application. You cannot just assume it’ll be correct, as you’ve discovered. Take a look at the Mill-Max or Preci-Dip catalogs to get an idea of what’s available.
help with a pdf in german. - Page 1
Forum section: electronics / repair

author: p.larner
author_rank: Frequent Contributor
timestamp: September 23, 2023, 10:23:48 pm
content: hi all,i have this grundig radio,its in good condition but is not as sensative as i feel it should be on some bands,i have the service manual for it but its in german,as its a scan it wont ocr to translate,i would like to know what inductors/coils i need to peak for each band,ie what coil /transformer to adjust for what bands,if that makes sense,can anyone help?,manual pdf attatched.

author: Swake
author_rank: Frequent Contributor
timestamp: September 24, 2023, 07:59:23 pm
content: Added OCR, it is still in German, and this made the file much bigger. 3 parts now.

author: Swake
author_rank: Frequent Contributor
timestamp: September 24, 2023, 08:00:45 pm
content: Part 2

author: Swake
author_rank: Frequent Contributor
timestamp: September 24, 2023, 08:01:59 pm
content: Part 3

author: DavidAlfa
author_rank: Super Contributor
timestamp: September 24, 2023, 08:52:16 pm
content: After optimizing and doing OCR on the original document, try google translator:https://translate.google.com/?sl=de&tl=en&op=docsResult:Download. (File too big for attaching).
Help with a Peak Atlas Gold ERS70  ESR meter repair  - Page 1
Forum section: electronics / repair

author: rfengg
author_rank: Regular Contributor
timestamp: December 23, 2024, 05:25:23 pm
content: Hi All,My Peak Atlas ERS70 Gold unit fails the Probe Compensation immediately showing the error message "Compensation Fail. Try again" even after several trials.The capacitance reading is still good but the measured ESR values are very high (~10 ohms even for a good quality cap that should be <1 ohm)Checked all the higher power resistors ( 33ohms and two of the 150Kohms) and they seem to be spot on.Any advice on what could be the reason for this?thanks,

author: aargee
author_rank: Frequent Contributor
timestamp: December 23, 2024, 09:10:08 pm
content: Resistance in the test leads? It may be measuring capacitance OK but can't handle current.

author: rfengg
author_rank: Regular Contributor
timestamp: December 24, 2024, 03:11:10 pm
content: @aargee Thanks for your suggestion but already tried it......the leads are perfectly alright when measured with a Keysight multimeter with less than 0.2ohms lead resistance.

author: Gyro
author_rank: Super Contributor
timestamp: December 24, 2024, 06:31:33 pm
content: Have you tried contacting Peak (not ideal timing, I know). They are normally very helpful in assisting their customers to repair their instruments.

author: TheDefpom
author_rank: Frequent Contributor
timestamp: December 25, 2024, 12:41:34 am
content: Quote from: Gyro on December 24, 2024, 06:31:33 pmI second this, Jeremy is a great guy to deal with, Peak also offer a repair service if it comes to that.

author: rfengg
author_rank: Regular Contributor
timestamp: December 26, 2024, 05:30:39 pm
content: @Gyro and @TheDefpom.....yes I did contact Peak thru their customer support but have not heard back.....hopefully they will get back once the holiday season is over.

author: Fraser
author_rank: Super Contributor
timestamp: December 26, 2024, 06:21:20 pm
content: I bought a known faulty DCA55 unit and contacted Jeremy for help. He not only offered a repair service, but also supplied a document that detailed testing and repair of the common fault that is caused by human error ! This was the fault in my unit and just required a common IC to be replaced. The service from Jeremy was truly brilliantHe has the traditional attitude of helping those owners who wish to attempt a repair themselves.Fraser
Help with a SMPS (Lytec LP5422 - Page 1
Forum section: electronics / repair

author: mark hodsman
author_rank: Contributor
timestamp: October 06, 2020, 01:10:22 pm
content: This LP5422 keeps blowing the mains fuses. (3Amp) I have checked the BR and can see no obvious short circuits on the board. However it keeps blowing the fuses in a dramatic fashion...Where should I look first off please? Im loathe to get stuck into this with 240V floating around. I'd be interested if I could inject 12 or 24V AC and still get meaningful test results.Thanks in advance!Mark H

author: goaty
author_rank: Regular Contributor
timestamp: October 06, 2020, 01:15:20 pm
content: Funny schematic, there´s no DC connected to the primary switching side ;-)Check Q1 for short first. Or output from U1 is constant ON...

author: mark hodsman
author_rank: Contributor
timestamp: October 06, 2020, 01:57:54 pm
content: I can confirm there is no connection to CN10 which is odd as you say...I can also reveal that the ZD2 is shorted and QN1 its shorted. I have an IRF840 kicking around -0 would that work in place do you think? Not sure about that Zener though

author: goaty
author_rank: Regular Contributor
timestamp: October 06, 2020, 02:03:56 pm
content: Not sure about the transistor specs, but make sure the UC3842 is not dead before trying out another Q1.The zener limits the gate voltage, but wouldn´t try it without it.

author: goaty
author_rank: Regular Contributor
timestamp: October 06, 2020, 02:38:38 pm
content: To avoid destroying fuses and components, you can put a lightbulb (60W) in series to mains. If it lights up bright, you know it isn´t working...

author: mark hodsman
author_rank: Contributor
timestamp: October 06, 2020, 04:43:14 pm
content: An update if anyone is interested...I put a 15V zener in place of the 18V and a IFR840 MOSFET and it lit up (in a good way) but it didn't work completely. Various aspects not working...then it gave up the ghost. Good news was that it didn't explode like a firework (this is progress)I guess it really needs an 18V zener - which I didn't have to hand.Do you think inserting exactly the right components would fix this? Why does CN10 not have anything connected? Any ideas?Thanks for all the help btw

author: goaty
author_rank: Regular Contributor
timestamp: October 06, 2020, 04:56:57 pm
content: The schematic is not complete, probably CN10 is for separating input circuit from switching circuit or as a test connector ?