hybridfree/eevblog-posts huggingface dataset:
Canon XHA1 Camcorder Repair Rant - Page 1
Forum section: electronics / repair

author: steve30
author_rank: Frequent Contributor
timestamp: March 17, 2022, 04:40:17 pm
content: I just wanted to rant about my Canon XHA1 camcorder. It is an HDV camera, so prone to issues with tape dropouts, but it is far more prone to tape dropouts than my Sony HDV cameras. I replaced the tape drive in it with a different one as the one it had had a mechanical fault, but I don't know how good my replacement tape drive is.I would like to look at the output from the head amplifier but I can't find where this signal is brought out. There are some connectors on the PCB which are just about accessible when the camera is assembled, but I've had a prod around with the oscilloscope and can't find the head RF signal anywhere. I could probe the amplifier chip itself but it is not accessible when the camera is assembled.Unfortunately I don't have the service manual for the XHA1 and can't find one anywhere. I do have the service manual for the XLH1, which is very similar electronics wise, and that does have the head RF brought out to a test connector, but the XLH1 is a very different form factor to the XHA1.If you are interested, here is a video of me poking around inside it:https://odysee.com/@steve30:3/canon_xha1_repair_rant:0If anyone has any useful service information they could provide, I'd be interested to hear it, but I thought I'd just post this here to rant.
Can't activate service menu LeCroy 9354AL x2 - Page 1
Forum section: electronics / repair

author: Lorenzo_1
author_rank: Regular Contributor
timestamp: November 04, 2023, 08:46:31 am
content: Having no success accessing service/maintenance menu on both my 9354AL units. Followed Tam Hanna's advice () - restarted, set to Auto then Stop. Service manual says press buttons 3&4 simultaneously then press 5. But no joy despite repeated attempts. I've been able to access on both units a year or more ago, though it can be finicky.One possibly relevant observation - all three menu buttons (3,4,& 5) give an audible click when pressed individually. When I press 3&4 before 5 to access service menu, both give an audible click. However, pressing 5 after 3&4 gives no click and to all appearances the unit is not detecting the button 5 press.Does anyone know if the absence of an audible click on button 5 after pressing 3&4 is normal or abnormal behaviour? If abnormal, seems strange that both units (otherwise fully functional) show same behaviour and neither is opening service menu. Is there some other trick or configuration needed to get this to work?

author: shakalnokturn
author_rank: Super Contributor
timestamp: November 05, 2023, 12:55:30 am
content: Stop acquisition, press return key to exit any menus.Press and hold 3, press and hold 4, press and hold 5, release 3, release 4, release 5.Not sure about the click, would have to try here.

author: Lorenzo_1
author_rank: Regular Contributor
timestamp: November 05, 2023, 04:33:19 am
content: Thanks - that fixed it. Pressed 3, then 4, then 5, released 3 and menu came up straight away.

author: MaxFrister
author_rank: Regular Contributor
timestamp: November 06, 2023, 02:37:25 pm
content: I also have a Lecroy 9310A that I used to be able to get into cal menu but can't anymore. If you look around the internet, there is lots of conflicting advice about which buttons to push in which order. At the time, ~5 years ago, I was not able to get any of them to work.In my case I think I caused the problem. The keypad had become very inconsistent and sometimes I had to push a button repeatedly to get it to register. The source of that problem turned out to be a real-time clock chip that would not shut-up but while troubleshooting I think i got too aggressive cleaning the keypad and/or flat flex.The scope is working except for the cal menu. IIRC the resistance on each press is in the hundreds of ohms. My theory is that that is low enough for single keys to register but not for the triple required press for the cal menu.It's on my list of things I should look into again.
Can't decode resistance value with color code - help! - Page 1
Forum section: electronics / repair

author: jrlemieux
author_rank: Newbie
timestamp: November 01, 2024, 01:04:15 am
content: Hello !I am trying to decode the resistance value for the R1 part on a PCB-0046, Electrolux 3164627 pcb 0046, es52x_36x PCB.Many people say it is a 221 ohms, but I am unable to confirm this value, as the colors on the resistance do not seem to be compatible with the 5 band color codes.The various pictures of the resistors were captured on the Internet, sorry if they are fuzzy.Is anyone able to decode the resistor value with certainty?Thanks !JL

author: themadhippy
author_rank: Super Contributor
timestamp: November 01, 2024, 01:22:26 am
content: does this help?Quote

author: Analog Kid
author_rank: Super Contributor
timestamp: November 01, 2024, 01:38:37 am
content: 220Ω, not 221 (red-red-brown). Almost the same difference, but still.

author: jrlemieux
author_rank: Newbie
timestamp: November 01, 2024, 03:11:37 am
content: I found that the 5th white band indicates that the resistor is a "fusible resistor".So it really is a 220-ish ohms resistor.Thanks

author: Greybeard
author_rank: Frequent Contributor
timestamp: November 01, 2024, 12:45:43 pm
content: https://www.mikrocontroller.net/attachment/546172/Fusible-Multicolor.pdf
Can't find this IC, it's on MSI Optix AG32C PC Monitor - Page 1
Forum section: electronics / repair

author: BC547B
author_rank: Contributor
timestamp: April 20, 2024, 08:57:08 pm
content: Hi, Has anyone seen this IC Before? The marking code on it is AEB it's 10 pin. Thank you.Background:- The problem with this monitor is that when you plug it via HDMI or DisplayPort, it says no signal.- The problem begun with weird flicker happening every morning when I turn on the computer and then it stabilizes and works well. I don't have an image of this problem but I found someone that posted a picture of the same problem:https://ibb.co/NFs26D5- Now it doesn't recognizes nor the DisplayPort nor HDMI. I haven't tried connecting via DVI yet, I've ordered an Adapter DVI to HDMI to see if it works.- I've tested 90% percent of the components on the board. These little devils are what's left, I don't know what they are, I don't know what they do. I've attached a photo of them.

author: fzabkar
author_rank: Super Contributor
timestamp: April 20, 2024, 09:12:10 pm
content: It's probably a TVS diode array for ESD protection. You should be able to remove it without affecting the operation of the monitor.Edit:https://pl.aliexpress.com/item/1005005472090433.htmlAEB = ESDU5V0AG4Bhttps://www.lcsc.com/datasheet/lcsc_datasheet_2203231830_Jiangsu-Changjing-Electronics-Technology-Co---Ltd--ESDU5V0AG4B_C2910045.pdf(datasheet)
Can't remove PCB from module - Page 1
Forum section: electronics / repair

author: jrlemieux
author_rank: Newbie
timestamp: October 29, 2024, 01:43:10 pm
content: Hello ! I am trying to remove a PCB from an oven control module. The PCB is held to the module by a strange clamp that I've never seen before. I can't figure out how to manipulate this clamp in order to allow me to remove the PCB. The lateral bars at top and bottom have some kind of spring, and they block the side parts that must likely be squeezed. Any clue anyone? Maybe it is an "insert only" clamp? Thanks! JL

author: ataradov
author_rank: Super Contributor
timestamp: October 29, 2024, 02:57:23 pm
content: It is hard to tell from a single picture, but from what is shown, it looks like you need to pull apart the side pieces and then press the actual clamp sides. I'm sure there is some tool that would let you do this in one press, but for now just jam a screwdriver and press the sides with pliers.

author: Russ_A
author_rank: Contributor
timestamp: October 29, 2024, 03:43:27 pm
content: It looks to me like it's in two pieces. The top and bottom parts might be pushed in first, and then there's space for the clamps on either side to be squeezed.

author: Kim Christensen
author_rank: Super Contributor
timestamp: October 29, 2024, 03:54:13 pm
content: There's probably some sort of removal tool to make it easier.You could DIY one out of a chopstick or similar:Make a wedge, when inserted in the gap, that will push in the direction of the yellow arrows. Have it no thicker (or less) than the green line.Then use pliers to squeeze the tabs in the direction of the orange arrows while pushing the wedge into the gap.An assistant, or a bit of pretension of the PCB, can help lift the PCB out off the clip.

author: jrlemieux
author_rank: Newbie
timestamp: October 31, 2024, 12:14:01 pm
content: Still can't work it out. I suppose we need a special tool for removal...

author: 807
author_rank: Frequent Contributor
timestamp: October 31, 2024, 01:12:17 pm
content: Quote from: jrlemieux on October 31, 2024, 12:14:01 pmHave you tried any of the above suggestions?On the face of it, it looks like you just need to move the top & bottom parts apart slightly to enable the side parts to be pushed in.

author: jrlemieux
author_rank: Newbie
timestamp: November 01, 2024, 12:48:12 am
content: I went to an appliance store since this was an oven PCB. The technician showed me how to disengage this type of clamp.It turns out that the top and bottom sections on my picture form anindependent partthat has to be pulled OUT of the clamp with a nose plier. Then, the two parts on the left and right can be easily squeezed to remove the board from the PCB.This clamp is thus made of two independent parts !!Greetings and thanks to everyone.

author: jrlemieux
author_rank: Newbie
timestamp: November 01, 2024, 11:44:03 am
content: For anyone curious, the is the inner part of the clamp.Regards.

author: ebastler
author_rank: Super Contributor
timestamp: November 03, 2024, 11:17:40 am
content: Quote from: Russ_A on October 29, 2024, 03:43:27 pmQuote from: jrlemieux on November 01, 2024, 12:48:12 amWho would have guessed?
Capacitor 2K 470 ELA, which ones can replace it? - Page 1
Forum section: electronics / repair

author: OverclockVintage
author_rank: Contributor
timestamp: October 08, 2021, 07:04:36 pm
content: Hi, i have here a notebook HP Pavillion g4 of which there is a swollen capacitor, it is this 2K 470 ELA, can it be replaced by a different one, which? or not? Thanks.

author: paul_g_787
author_rank: Frequent Contributor
timestamp: October 08, 2021, 08:18:56 pm
content: I believe that is a 470µF capacitor.You can replace it with another 470µF capacitor of the same or higher voltage rating.Not sure about the ELA though. I am not familiar with that coding.Could you perhaps upload a photo of it showing the markings?

author: OverclockVintage
author_rank: Contributor
timestamp: October 08, 2021, 08:33:35 pm
content: Sure, here it goes:

author: paul_g_787
author_rank: Frequent Contributor
timestamp: October 08, 2021, 08:53:48 pm
content: I managed to find this:https://electronics.stackexchange.com/questions/500183/aluminium-electrolytic-capacitor-information-top-marking-9h-100-elaSo I believe that the E indicates 25V and the LA is the manufacturer's series ID.So you need a 470µF 25V Aluminium Electrolytic capacitor.Maybe like this:https://cpc.farnell.com/panasonic-electronic-components/eeefk1e471p/capacitor-case-g-470uf-25v/dp/CA07884Although be sure to check the pin spacing and the diameter / height of the new capacitor to make sure it will fit in place.

author: OverclockVintage
author_rank: Contributor
timestamp: October 08, 2021, 09:05:11 pm
content: Thank you, i will do that, i think it will be easy to find.

author: paul_g_787
author_rank: Frequent Contributor
timestamp: October 13, 2021, 07:46:52 pm
content: Remember, if you cannot get a 25V one you can use a higher voltage rating such as 35V or 63V (assuming it in not physically too large). It is only the max voltage rating.Just don't connect it backwards (not that I have ever done that of course)
Capacitor FanSpeed control - Page 1
Forum section: electronics / repair

author: zar0079
author_rank: Newbie
timestamp: February 20, 2024, 07:58:51 am
content: HelloWhat is the value of a capacitor?Can replace with film capacitorFanSpeed control classic car run only 1 stepThank

author: Greybeard
author_rank: Frequent Contributor
timestamp: February 20, 2024, 09:15:08 am
content: https://www.electricaltechnology.org/2022/01/capacitor-color-codes.html
Capacitor help needed. - Page 1
Forum section: electronics / repair

author: eurgenca
author_rank: Regular Contributor
timestamp: September 28, 2020, 09:30:00 am
content: Hello.Does anybody have idea what kind capacitor could be this fellow.Marking is J1S2J.I have no idea.Thanks, Seba.

author: lordium
author_rank: Regular Contributor
timestamp: September 28, 2020, 10:11:13 am
content: It is probably 2J152J. 630V 1.5nF +-5%? seehttp://kaizerpowerelectronics.dk/theory/capacitor-code-table/for examples

author: eurgenca
author_rank: Regular Contributor
timestamp: September 28, 2020, 02:37:15 pm
content: Thanks this is cool.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: September 29, 2020, 10:18:48 pm
content: That capacitor is dead.It is no more.That capacitor has ceased to be.
Capacitor ID - Page 1
Forum section: electronics / repair

author: Krashkource
author_rank: Newbie
timestamp: October 03, 2020, 02:38:45 am
content: I have been trying to figure which capacitor this is in the attached image. Its listed as a 310 330 6z so I am assuming it is a 330 uF 6.3 Volt DC since the z seems to indicate +80%/-20%. Am I reading this correctly? This is on an AGP video card I am attempting to restore.https://vgamuseum.ru/gpu/nvidia/nvidia-riva-tnt2-m64-number-nine/Thanks for any info before I completely fry the card.

author: coromonadalix
author_rank: Super Contributor
timestamp: October 03, 2020, 03:36:31 am
content: i would say yeshttps://www.electronics-notes.com/articles/electronic_components/capacitors/capacitor-codes-markings.php
Capacitor identification - Apogee Alta U4000 CCD camera - Page 1
Forum section: electronics / repair

author: flolic
author_rank: Frequent Contributor
timestamp: January 14, 2020, 11:17:08 pm
content: I am repairing old Apogee Alta U4000 CCD camera that has bunch of dead axial capacitors inside. Almost all of them has corroded positive terminal, to the point that + leg fall of when you try to desolder them.Are those standard aluminium or tantalum?Vishay ones are obviously replaced previously.Capacitors are 68uF/16V.Thanks,Filip

author: andy3055
author_rank: Super Contributor
timestamp: January 15, 2020, 01:14:06 am
content: They are standard Aluminum electrolytic caps.

author: Pete66
author_rank: Regular Contributor
timestamp: January 16, 2020, 05:46:37 am
content: Vishay ones appear to be bipolar.

author: andy3055
author_rank: Super Contributor
timestamp: January 16, 2020, 05:56:29 pm
content: By the way, the board has markings for the polarity of the caps. Pay attention to those when you do the replacements.

author: flolic
author_rank: Frequent Contributor
timestamp: January 16, 2020, 07:59:31 pm
content: Thank you all.I replaced all of them with good quality low esr 105C from Panasonic and camera is working fine (after installing new KAI4022 CCD sensor).I used standard radial ones that I had, and bent one leg to the other side.

author: free_electron
author_rank: Super Contributor
timestamp: January 16, 2020, 08:50:09 pm
content: old philips capacitors.

author: flolic
author_rank: Frequent Contributor
timestamp: January 19, 2020, 08:39:56 am
content: Anyone know how to properly purge sensor chamber with Argon? I replaced desiccant but anyway got some condensation on the CCD sensor.Usually sensor is cooled to -20 to -30C.There are two 1/4" 20TPI charging ports on the back side of camera, each have spring loaded ball check valve. Should I just pressurize chamber with Argon, or should I also connect vacuum pump on the other port?It is my understanding that chamber should stay at positive Argon pressure relative to atmosphere to avoid air to leak back in. But how much pressure?My camera obviously leaked through hermetic electrical connection feed through, because (sealing epoxy?) was partially unglued from the housing. Also there are some traces of corrosion.

author: flolic
author_rank: Frequent Contributor
timestamp: January 19, 2020, 07:16:25 pm
content: Anyway, I successfully purged the chamber, no more condensationFirst I connected the vacuum pump to the suction port near the power and USB connectors and pulled the air from the chamber. Then I connected Argon bottle (via the pressure regulator) to the charging port and slowly let the gas in.You can not "overfill" the chamber, any excessive pressure will vent out through the suction port.My camera can now reach at least 60C temperature difference, before it was struggling with 50C
Capacitor Identification - Page 1
Forum section: electronics / repair

author: Sparky49
author_rank: Regular Contributor
timestamp: April 26, 2020, 04:56:07 pm
content: I'm replace a few capacitors from a bit of gear made (I think) in the 60s. However I'm having some uncertainties about certain capacitor values as I cannot find any schematics for this instrument on the internet (Advance Instruments TC9 B/S). Would anyone be able to check my assumptions for the following capacitors please?The first is in series with the signal input - I'm guessing this is a 0.15uF 400V capacitor - but I'm not familiar enough with the different cap types to know if it is paper/polystyrene/whatever. What would be a good substitute here?The second picture shows a large green capacitor on the main board for the nixie tubes. Initially I presumed this was a 4.7 mF capacitor (4700uF), but my LCR meter measured it as 4.9uF, so now I am assuming this is 4.7uF. I also assume this is for 160V, but please correct me if I'm wrong on this too.Finally there is this arrangement on the mains input. I presume this is a 5000 pF capacitor - for 3000V? I'm not sure what the yellow component is - it has DCC TYPE 666 1 AMP 6937 written on it.Here is the schematic of the two lots of this components - I presume it is a mains filters, so the yellow component is an inductor of sorts. Any idea for value?

author: octillion
author_rank: Contributor
timestamp: May 01, 2020, 03:23:32 am
content: The first capacitor is some sort of film, 0.15 uF 400 V. No need to replace it if it tests good (film don't tend to fail with age).The second is 4.7 uF 160 V. On old capacitors/documents "MFD" means micro-Farad (uF), and MMFD is micro-micro-Farad (pF).The third is 5000 pF 3 kV ceramic capacitor, used for RFI suppression if it is placed across the line and ground. No real need to replace if it tests OK, but you could replace it with a modern Y-class safety capacitor. The yellow thing is seems to be heat shrink over a 1 A fuse.
Capacitor identification help - Page 1
Forum section: electronics / repair

author: Lorenzo_1
author_rank: Regular Contributor
timestamp: February 23, 2021, 01:08:54 pm
content: I have two main boards from APC SURT1000 double conversion UPS with faults. Trying to identify the pictured blue capacitor marked u1J63 on one side and A(?)107 on the reverse. Pretty sure it's 100nF 63V +/-5% but not sure of its internal composition. The second board (also pictured) has an orange capacitor marked 0.1 J 63 in the same location (C93) - which looks like the same spec. They bridge between pin 5 on the TC4427 IC, which is a dual MOSFET driver and the pin on T6 nearest the C93 PCB mark.Are both of these perhaps polyester film caps? Happy to post other board pics if that helps with identification.

author: MF-jockey
author_rank: Regular Contributor
timestamp: February 24, 2021, 11:11:05 pm
content: 0.1 µFJ= 5%63 Vif not sure the best type is MKP (Polypropylen)Polyester has big ESR and tan δ

author: Lorenzo_1
author_rank: Regular Contributor
timestamp: February 25, 2021, 09:46:19 pm
content: Thanks for the confirmation and guidance re type,
Capacitor nominal values versus measured - Page 1
Forum section: electronics / repair

author: negativ3
author_rank: Regular Contributor
timestamp: June 02, 2023, 06:47:36 am
content: Hi all,During repair of a bt keyboard recently, I noticed the BMS circuit used an electrolytic on the input side. It did not show any signs of degradation at all but just out of curiosity, I removed it and measured it. Labelled capacitance was 470uF @ 10V but it only measured 20.8uF so I replaced it.Was this a sensible move, and was it a lucky catch?The BMS chip is a TP5000 and the keyboard uses USB to charge.ThanksAndy

author: Aheld
author_rank: Regular Contributor
timestamp: June 02, 2023, 05:55:36 pm
content: Hi, can you tell us a little bit more how you measured this value?Br. Axel

author: Swake
author_rank: Frequent Contributor
timestamp: June 03, 2023, 06:24:36 am
content: Aheld has a good question, but I'll assume you used a multimeter to measure the cap and that you measured the new cap to compare.Does it charge now? Because if that keyboard is working again you likely found the issue replacing that cap.Lucky catch or 'electronics intuition'. Call it what you want, the fact is you tried to repair the keyboard with the knowledge you had and that made you take a decision. Turns out that you at least found a dirty cap.

author: negativ3
author_rank: Regular Contributor
timestamp: June 03, 2023, 04:10:41 pm
content: Hi guys, I used an LCR meter.The keyboard is less than three years old and there was no sign of a dodgy cap and except for curiosity of the only electrolytic, I guess I got lucky.

author: MathWizard
author_rank: Super Contributor
timestamp: June 04, 2023, 05:48:14 am
content: I'm not sure the real reason why, but my LCR meter, the higher the frequency I test at, the lower it reports the capacitance. So that doesn't sound too weird. I'm sure I've measured 100uF caps at 100kHz, and the meter, however it calculates it, would say 10-20uF, or something like that for larger caps. But at low freq, allowing it to charge, like with a DMM, they would read within tolerance, which is often like +/-20%.So I usually ignore it, and just go by the ESR at 100kHz, and dissipation Factor at 1kHz (or 120Hz for that I can't remember)

author: wraper
author_rank: Unknown
timestamp: June 04, 2023, 06:16:56 am
content: With LCR meter you should primarily measure ESR or resistance/impedance (at AC current) because capacitance often looks fine but capacitor is already dead. Also measuring in resistance mode usually works fine in circuit.

author: Aheld
author_rank: Regular Contributor
timestamp: June 04, 2023, 03:15:38 pm
content: There is a very good application note from Wuerth Electronics, related to capa value and frequency and also which capacitor for what application and why. I‘m not sure if it is also available in english.So, if you say measurement frequency at 100kHz then you wouldn‘t get the expected 100uF. Reduce frequency to 100Hz then it will show you 100uF.The relation will be listed in datasheets of capacitors.For me the behavior of the elko looks fine.
Capacitor Reforming - Page 1
Forum section: electronics / repair

author: Adam Baum
author_rank: Newbie
timestamp: May 07, 2023, 01:40:51 pm
content: Reforming Capacitors - Everything you wanted to know6 May 2023Capacitor Reforminghttps://caps.wiki/wiki/Capacitor_ReformingReference materials:https://www.tdk-electronics.tdk.com/download/530704/e724fb43668a157bc547c65b0cff75f8/pdf-generaltechnicalinformation.pdfhttps://chemi-con.com/wp-content/uploads/2021/04/Technical-Notes.pdfhttps://www.hb9aik.ch/notes/MIL-HDBK-1131C.pdf
Capacitor substitution  - Page 1
Forum section: electronics / repair

author: Dapp927
author_rank: Newbie
timestamp: October 08, 2024, 04:24:45 pm
content: Greetings all! I'm doing a recap on a Paco C-20 and C9 calls for a .02 uf, 400V, tubular, precision. Can I use one of these three, or do I need to get the exact capacitor? Thanks in advance!

author: TimFox
author_rank: Super Contributor
timestamp: October 08, 2024, 04:54:22 pm
content: Quote from: Dapp927 on October 08, 2024, 04:24:45 pmNone of those units is "precision", apparently 10% or 20% tolerance.What is the purpose of C9 in that unit?Normally, to replace a 400 V tubular capacitor, I would use an axial-lead polypropylene unit, with voltage rating 400 V or more (600 and 630 V are common).If you have an LCR meter, you could sort a few to get the best result, or buy 0.01 uF units and sort to get a good pair.

author: Dapp927
author_rank: Newbie
timestamp: October 08, 2024, 08:13:08 pm
content: Thanks Tim! I’m in the process of ordering this one from DIGI-KEY. Ironically, the capacitor is for a capacitor testerI can’t make this stuff up

author: TimFox
author_rank: Super Contributor
timestamp: October 08, 2024, 08:15:27 pm
content: That should work. The extra price is probably due to the tight tolerance, 2%.
Capacitor value - Page 1
Forum section: electronics / repair

author: salviador
author_rank: Regular Contributor
timestamp: January 16, 2025, 06:38:14 pm
content: What do you think the value of this capacitor is, with the 98pF capacitance meter, but it's strange

author: Dougmc
author_rank: Contributor
timestamp: January 16, 2025, 06:45:55 pm
content: kinda looks like a MOV rated at 275v.does it have any resistance ?

author: coromonadalix
author_rank: Super Contributor
timestamp: January 16, 2025, 06:46:55 pm
content: same here i would have said movwould be theses serieshttps://www.soselectronic.com/en-nl/products/vishay-bc-components/593-275-vdrs07h275bse-20473

author: salviador
author_rank: Regular Contributor
timestamp: January 16, 2025, 07:01:35 pm
content: maybe you're right, I was about to replace it with a 5.9nF capacitor .thank you very kind guyshttps://www.soselectronic.com/en-nl/products/vishay-bc-components/594-275-vdrs10p275bse-20481
Capacitor Value? - Page 1
Forum section: electronics / repair

author: jimmyblacksmith
author_rank: Newbie
timestamp: February 26, 2024, 03:39:14 am
content: What value is this polyester capacitor? Marked: MW-F .22/K

author: wraper
author_rank: Unknown
timestamp: February 26, 2024, 03:40:25 am
content: 0.22uF +/-10% 630V

author: Zero999
author_rank: Super Contributor
timestamp: February 26, 2024, 09:07:32 am
content: Do you think the capacitor is faulty? The photograph only shows superficial damage. I recommend testing it, before replacing it, unless you know for sure it's faulty.
Capacitor voltage rating range? - Page 1
Forum section: electronics / repair

author: mitch
author_rank: Newbie
timestamp: November 30, 2019, 08:50:01 am
content: I have a capasitor that's rating is 189...227uF and Un 250V~/Up 275V~ I found one that is 189...227 and 220-250 volt.My question is will the 220-250 volt capacitor work with the 250-275 volt? They both are rated for 250 volts, right? Is that rating a range between the two numbers?New?https://www.amazon.com/gp/product/B00C0VZA0W/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

author: trobbins
author_rank: Frequent Contributor
timestamp: November 30, 2019, 10:11:55 pm
content: Un is the rated continous rms max voltage. Up is a short duration, limited no of events, peak rms level that doesn't cause degradation. Similar to electrolytic ratings that comply with xxxx standard.

author: mitch
author_rank: Newbie
timestamp: December 01, 2019, 04:43:38 am
content: Quote from: trobbins on November 30, 2019, 10:11:55 pmSo Un220 & Up250 for the one on Amazon, so it could work?I'm completely new to electronics.

author: bob91343
author_rank: Super Contributor
timestamp: December 01, 2019, 04:54:40 am
content: The closer you run a capacitor to its voltage rating, the lower its reliability. So using the lower voltage unit won't cause immediate problems but the long run is grim.It's usually wise to provide a voltage rating higher than necessary in order to stave off the degradation that occurs with more voltage stress. Once the capacitor develops a slight leak in current, that warms it and raises the temperature. And temperature is the primary cause of failure.
Capacitors for CRT low impedance or general purpose? - Page 1
Forum section: electronics / repair

author: iLoveCRTs
author_rank: Newbie
timestamp: September 15, 2022, 09:50:49 pm
content: Hi! I need to replace 2/3 capacitors on my CRT TV and I'm thinking about ordering em from Mouser. When ordering capacitors specific for CRTs should i go for Low Impedance or General Purpose? Also does Ripple current matter? Thanks!

author: strawberry
author_rank: Super Contributor
timestamp: September 15, 2022, 11:32:12 pm
content: generally doesnt matter (same capacitance and size that can fit and voltage rating same or higher) sometimes can do experiment with higher capacitance to bring down ripple ...low ESR /high ripple current/long life capacitors are betterlarger size capacitors will live longer than miniaturefor 2k vintage it wont make it more valuable installing higher quality components (maybe after 40y)

author: iLoveCRTs
author_rank: Newbie
timestamp: September 16, 2022, 02:01:43 am
content: I see, thank you so much
Capax 7-77 variable speed trigger switch - reassembly driving me nuts - Page 1
Forum section: electronics / repair

author: Lomax
author_rank: Frequent Contributor
timestamp: July 28, 2025, 03:45:31 pm
content: I found a decent-ish corded drill the other day, which looked virtually unused despite being old enough to have been manufactured in the Old Dart. Only problem was it would only run at full blast; the 0-3000rpm promised by the label having gone missing. I suspected what had happened was the drill had been left in the sun, and the gearbox lube had turned liquid, coating every surface of every contact inside. The state of the carbon brushes and, later, the innards of the trigger switch certainly seemed to suggest this was the case. I managed to get the trigger mechanism opened without too much trouble and the dual printed potentiometers were indeedsoakedin oil. I've cleaned it all up which has restored the variable speed function, but I now find myself unable to re-assemble the trigger mechanismIt's the switching part that's got me stumped, despite consisting of only three moving parts: a spring, a large contact element, and a small contact element. It's driving me nuts.I've spent (no exaggeration) the best part of a day trying to figure out how these pieces fit together but I'm getting nowhere. Thought I'd check here if anyone has dealt with anything similar? See photos below...

author: Lomax
author_rank: Frequent Contributor
timestamp: July 28, 2025, 03:54:52 pm
content: In case it's not clear from the images what the issue is: the large contact element never makes contact with the two screw terminal it's supposed to alternate between, and the small contact element makes contact with both and/or the wrong one, depending on the trigger position. Basically just completely wrong.
Caps leaking underneath? - Page 1
Forum section: electronics / repair

author: bcg
author_rank: Newbie
timestamp: February 04, 2024, 07:51:37 am
content: Old Amstrad power supply out of a PC2286.Going to fix it for a little project.I don't do a lot of repairs.I like my failed capacitors to be nice and bulgy. Reckon these have leaked underneath? Maybe from the top then the goop has made it under the board? Perhaps the machine was stored at an angle.

author: selcuk
author_rank: Frequent Contributor
timestamp: February 04, 2024, 08:17:46 am
content: Coffee or coke?

author: Haenk
author_rank: Super Contributor
timestamp: February 04, 2024, 08:51:15 am
content: Bulging does only happen, when in use - when the computer has just been stored away, the rubber seal failed and the cap leaked. Absolutely common issue.

author: p.larner
author_rank: Frequent Contributor
timestamp: February 04, 2024, 10:13:09 am
content: i cant see any leakage,why not meassure capacity+esr before asking?.

author: factory
author_rank: Super Contributor
timestamp: February 04, 2024, 11:25:24 am
content: Those Nichicon PL caps are peeing conductive /corrosive electrolyte, this is getting very common with 80s & 90s capacitors, the seals seem to fail around the negative lead.I recommend you remove them, clean the board & fit some quality replacements, from a reputable supplier (not ebay amazon Ali etc) . Check the others too.David

author: bcg
author_rank: Newbie
timestamp: February 14, 2024, 05:41:18 am
content: Because I don't have an ESR or capacitance meter? :-p

author: bcg
author_rank: Newbie
timestamp: February 14, 2024, 05:42:31 am
content: A visit to mouser and it's now going again.Was lazy and just replaced the big caps.
Capstan motor repair for Pioneer CT-F1250 - Page 1
Forum section: electronics / repair

author: Bargainhunter
author_rank: Regular Contributor
timestamp: April 23, 2025, 08:32:23 pm
content: Has anyone disassembled the capstan motor on a CT-F1250?If so, is there supposed to be a washer on the inside?I don't mean the oil stop washer.Thank you

author: Jeff eelcr
author_rank: Frequent Contributor
timestamp: April 25, 2025, 01:29:44 am
content: In the early eighties I repaired many small motors I do not remember any without some type of internal washer, thin plastic mostly.BUT memory is not what it was then.Jeff

author: wilfred
author_rank: Super Contributor
timestamp: April 25, 2025, 02:11:07 am
content: By some serendipitous coincidence only yesterday I watched a video on the "repair" of a CT-F950 deck "reel" motor and assuming they share similar motors it might have the answer to your question. It is pretty clearly photographed so it should be immediately apparent if they are similar. However it does say reel motor and it is less likely the reel motor and capstan motor are internally the same but there it is. It might have other useful information regardless.this is the link cued at 13:00 after the painful process of removing the back cover of the motor.https://youtu.be/CHBsvWASkoc?si=FeaKyhL9yczGiRXi&t=780
STA-10 Car Amp Repair - Page 1
Forum section: electronics / repair

author: edPP
author_rank: Newbie
timestamp: November 11, 2022, 10:41:38 pm
content: Hi, first post so I'll try to do this right.I am trying to re-teach myself some electronic repair as a hobby, I play too many video games but am getting old and bad at that. I got a cheap broken car amp to repair - a PowerBass STA10, class D amp.This is despite not having a car, or interest in bass. Symptom is no audio output. Scope shows signal l going to -ive driver terminal, none to +ive. Signal responds to gain control where present. Putting scope aside due to lack of qualifications...I know the first thing to check are transistors and rectifiers, so opened the lid on her and count:1x TIP41C - NPN - right hand side -https://www.st.com/resource/en/datasheet/tip41c.pdf2x IRF540N - N-Channel - right hand side -https://media.digikey.com/pdf/Data%20Sheets/Fairchild%20PDFs/IRF540N.pdf2x PTP16N06N - N-Channel left hand side1 (each) x MUR1220CT/CTR- - rectifier - left hand sideI don't see any charring, but have not removed the PCB yet to check the underside. No definitive magic smoke smell either (I am an expert on breaking things so would stand to know).The right-hand side heatsink has some white paste that, to my untrained eye, seems to have spread out over the bar - as if it has melted, as attached. I have a cheap multimeter - a Ragu 81D. I don't trust it, because it is cheap, so I have a Fluke on the way - yay, a collection. But owing to my ill-informed suspicions I have probed ahead anyhow around this area.TIP41C - tested per this sitehttps://vetco.net/blog/test-a-transistor-with-a-multimeter/2017-05-04-12-25-37-07Whilststill in the circuit.Step 1: (Base to Emitter): 0.67VStep 2: (Base to Collector) 0.67VStep 3: (Emitter to Base) 2.7VStep 4: (Collector to Base) rises slow to 2VStep 5: (Collector to Emitter) rises slow to 2VThe IRF540Ns also look dodge, but I'll save typing that up until a good person tells me it might be useful.Does a kind soul have input to offer and ease my learning experience? I am tempted, on the basis of the mess and above, to desolder the TIP41C and measure in isolation. But don't have so much time that I want to do unnecessary stupid's, because then there would be far too many in this regard.Ed
Car instrument cluster lcd - Page 1
Forum section: electronics / repair

author: ants2
author_rank: Newbie
timestamp: September 10, 2025, 01:20:49 am
content: Hi my odometer is not working correctly, I tried putting in a replacement lcd.. still the same. It just plugs in like ram. I tried checking the lcd pins go to the board with an ohm meter. Most lcd wires seem to run to a chip. What's most likely issue , bad joint?

author: coromonadalix
author_rank: Super Contributor
timestamp: September 10, 2025, 03:00:22 am
content: depends on how the lcd is made / built, could be what we call zebra strips, bad contact pressure between lcd glass and pcb / support, bad solders .. hard to tell like thisit is the second you put in it, could be driver ic related seems a row is missing, you need to search the pinouts, driver ic markings etc ... unless the lcd itself has a driver ic embedded in it ?

author: ants2
author_rank: Newbie
timestamp: September 10, 2025, 03:54:48 am
content: Here is the old one, I tried heating the pins up before getting a replacement.. I saw videos about zebra strip repair but this appears sealed. No ic on the lcd. Reading should be around 389000 I think, I wouldn't care but the government is putting Tax per km driven next year
car radio bulbs no longer working - Page 1
Forum section: electronics / repair

author: BillStrachan
author_rank: Newbie
timestamp: December 23, 2024, 11:35:13 pm
content: i have a radio from a 06 silverado and i soldered in new led bulbs into the display and they shorted out when i plugged the radio back in. everything still functions but the lights are all out. i found that one of the bulb pins was protruding too far past the board and touched a backing plate which i believe grounded out causing all the bulbs to no longer turn on. i took apart the radio again and the bulbs still work when i put 12 volts to the display board separately. so something on the board got damaged and im curious if i can replace a component on the board rather than order a whole new used radio off ebay. i dont exactly know what to look for but i havent seen any burnt components on the board.

author: Jeff eelcr
author_rank: Frequent Contributor
timestamp: December 24, 2024, 01:45:42 am
content: First check for blown fuse/s in vehicle if not any and problem is on main PCB track backwards from where you shorted it.Look for open resistors/ transistors/ regulator IC's or what you could have damaged.Jeff

author: CatalinaWOW
author_rank: Super Contributor
timestamp: December 24, 2024, 04:04:46 am
content: Don't know about this radio, but in some the lights are on a different circuit than the radio itself. So the radio may play with the lights out due to a car level fuse.

author: Swake
author_rank: Frequent Contributor
timestamp: December 24, 2024, 08:48:39 am
content: Back in the day the lights in a radio only came on when the lights of the car itself where on (dim or high beam). There was a separate wire for this.

author: Robert763
author_rank: Super Contributor
timestamp: December 25, 2024, 02:15:49 pm
content: Did you put resistors in series with the LEDs?
Card extender suggestions - Page 1
Forum section: electronics / repair

author: Lorenzo_1
author_rank: Regular Contributor
timestamp: June 29, 2021, 01:56:21 pm
content: Looking to make an extender for the control board on an APC SURT1000 to allow access to the plug-in control board signals. Attached are photos of the double-sided 2x28 pin connector with alignment slot. Pitch is ~2.5mm with a 2mm wide pad, Board is 1.6mm thick. Have searched online for a suitable connector - can find options for a female socket that look probably suitable but need to parts (male connector, short cable (easy to find), and female socket) to make an extension adapter. Female socket on main board is 83mm x 10mm,Can anyone identify this type of connector and point me in the right direction to find one? Also need to find a male analog of the PCB edge connector that I can solder or otherwise connect to. Hoping to find a way of doing this with off-the-shelf items. Suggestions welcome.

author: YetAnotherTechie
author_rank: Regular Contributor
timestamp: June 29, 2021, 08:26:37 pm
content: it's a standard 60 way edge connector:https://pt.mouser.com/ProductDetail/EDAC/345-060-520-201?qs=U4pz39agNJCLt%2Fy2FwFazg%3D%3DYou can get "ISA prototype board"s on ebay, they have one extra pin, so you have to file the edge.

author: fzabkar
author_rank: Super Contributor
timestamp: June 29, 2021, 11:15:35 pm
content: Quote from: YetAnotherTechie on June 29, 2021, 08:26:37 pmCould an ISA riser card be adapted for this task (with a hacksaw)?https://www.ebay.com/itm/333606618217https://www.ebay.com/itm/193927755824

author: Lorenzo_1
author_rank: Regular Contributor
timestamp: July 02, 2021, 11:37:10 am
content: Ordered one of these - overlaying images suggests I should be able to cut the interface down and use it. Will report on whether it works.
Mr Carlson's Lab Spectrum Analyzer's Protection Circuit - Page 1
Forum section: electronics / repair

author: Smoky
author_rank: Frequent Contributor
timestamp: September 23, 2021, 11:01:15 pm
content: Hey Folks!I'm looking to align older radios in the future and I want to use my spectrum analyzer during the process. Paul's spectrum analyzer is an HP3585B and it has an optional 1MOhm input. I bought a good/used HP3588A not long ago and it has a switchable 50/1M Ohm input. The difference is, the max voltage on my spectrum analyzer's input is 4 volts Pk:I want to make a protection circuit just like his but mine will require a different number of diodes and capacitors and I was hoping you can let me know if I'm figuring things right, primarily, the amount of capacitance. The first thing different that I want to do is just to make a dedicated cable, I don't want to attach BNC's to the circuit's project box and all of that. One other thing too, I plan to use a small Pomona 3753 aluminum project box so I may not want it near the end of the probe's cable either. Also, I'd like to have the circuit and the cable shielded from the BNC attached to the spectrum analyzer all the way to the tip of the probe so I'd plan to use RG316.As for most of the stuff I do, it's for fun and practice, and in the end, I'm hoping to use this spectrum analyzer and a Heathkit VTVM for radio alignmentsWhat parts I have for the circuit so far are 62pf/500v capacitors and 1N914 100v/200mA diodes. I'll have to make the circuit the point-to-point way.

author: Smoky
author_rank: Frequent Contributor
timestamp: September 23, 2021, 11:29:27 pm
content: I wanted to tackle the probe side of the circuit to see if I could get shielding up to the point of attachment to the radio's circuit. I searched around and I found these Kelvin clips:They turned out to be really cool. The tip's blade can be un-screwed and soldered. The blade is thick and the tip has serrations that look like they'd grip really good to the component under test. The clips cost $2.50 each.I started by stripping-back the RG316 to expose the center conductor and shielding braid. I'm using an E-Z Micro Hook for the ground lead. I bought a 12" one (204XM-12BLK, ~$5) and cut it in half. Btw, that dinky thing is rated for 1kV!I slipped the cables through the handle of the Kelvin clip and soldered the ground lead and the center conductor in place:It really turned out nice. The Kelvin clip is small but its mouth can open to 1" tooHere's where the project stands at the moment ready for some figuring and measuring:

author: coppercone2
author_rank: Super Contributor
timestamp: September 24, 2021, 03:15:36 pm
content: I think you can shore it up with a GDT but I think you would need some ballasting because of trigger time. I read something interesting just now where someone claims that a coaxial cable separating it from the diodes of some length might be enough to do it, where you might want local protection on the antenna followed by this circuit at the input of the SA if its remote enough
Carrier/Bryant Fan Motor ECM 2.5 - Page 1
Forum section: electronics / repair

author: L_Euler
author_rank: Regular Contributor
timestamp: September 15, 2019, 12:45:34 pm
content: I have a failed ECM on my HVAC air handler. The control board that communicates with the thermostat and also signals the blower drive is PIC18F based. On my unit (ECM 2.5) there are four signal wires and two 240VAC power wires going to the ECM. I really want to set up a test fixture for this thing, but I can't find any background on the signaling between the control board and the ECM. Also there appears to be some industry standards for ECMs, but apparently it is some state secret. I can find devices that will test ECMs, but they are version dependent, 2.3, 2.5, 3.0, etc. and I can't find clarity on which one is which. So my question: Do any of you have understanding of ECM standards, if they exist, and what the signaling is?

author: duak
author_rank: Super Contributor
timestamp: September 16, 2019, 01:13:26 am
content: I have a Carrier furnace and heat pump system with the Infinity (Evolution for Bryant) control. It works well and has some spiffy features but is apparently expensive to repair. It's said of Carrier that you can always get better, but you can't pay more.Anyhoo, I understand the Infinity control interface (ABCD or Communicating) is two lines for 24 VAC and two lines for bidirectional serial data with RS-485 levels. It's a closed system and I've occasionally found dribs & drabs of info as experimenters have tried to reverse engineer it. eg: using "carrier infinity protocol" as a search term I find things like this:https://forums.homeseer.com/forum/thermostat-hvac-plug-ins/thermostat-hvac-discussion/47625-anyone-talking-to-the-carrier-infinity-systemhttps://us.v-cdn.net/6031006/uploads/vbulletin_attachments/1/5/2/3/557.pdf

author: L_Euler
author_rank: Regular Contributor
timestamp: September 16, 2019, 11:21:20 am
content: Quote from: duak on September 16, 2019, 01:13:26 amThanks for the links. Interesting stuff. Communication from thermostat to local controller in air handler is solid, and controller to blower ECM is good, I assume. I'm trying to understand the communication between the local controller and the ECM so that I can build a test fixture. I have two of these units and I put a scope on the control line to the ECM of the known functioning unit. The local controller communicates to the ECM with a serial link and looks to be transmitting two or three 8-bit words. I need to understand the content of that serial transmission.

author: kevinateev
author_rank: Regular Contributor
timestamp: March 15, 2020, 03:33:03 am
content: @L_Euler I just completed a diagnostic tool exactly for this. It is on GitHub at :https://github.com/kpishere/Net485/tree/master/diag/net485ListenIt listens only. There are a number of hardware options available to you to get RS485 to USB. Check out the wiki in that repository for an example of my rig, easily available parts from China.
Cary SLP 03 Preamplifier hiss.. help with service manual/schematic? - Page 1
Forum section: electronics / repair

author: CHexclaim
author_rank: Regular Contributor
timestamp: December 29, 2022, 03:56:12 pm
content: Hello community and happy new 2023 for you and yours.A Cary model SLP 03 Preamplifier came in for service. It has a horrible hiss in both channels. It is very well constructed and have been looking around for visible probable causes, bad components, etc., but nothing looks bad. Tubes are not the issue either.Before starting a deeper disassembly with no information I was wondering if someone can point me to some technical information on this unit, schematich, service manual, or, information on what to look for first.Very appreciated.Regards, Carlos.

author: Smoky
author_rank: Frequent Contributor
timestamp: December 29, 2022, 04:39:58 pm
content: Hello Carlos, I live just a few blocks from Cary Audio here in Raleigh, North Carolina.If you contact them through e-mail at techsupport@caryaudio.com you will get a reply.There are a lot of parts and especially resistors in that preamplifier so maybe they can help narrow it down.Good luck

author: CHexclaim
author_rank: Regular Contributor
timestamp: December 29, 2022, 05:22:39 pm
content: Hi, thank you for your reply.Requirements for service stated on the user manual are, at least, discouraging.Unfortunately I'm located in South America so it is difficult to send the unit in for repair. I'll try to contact them but I will not have high expectations.. Lets se..Thanks.