hybridfree/eevblog-posts huggingface dataset:
Help find compatible switch - Page 1
Forum section: electronics / repair

author: S0N1C
author_rank: Newbie
timestamp: June 20, 2019, 07:56:33 pm
content: Hi all,switch for selecting tape type on my Walkman DD11 is broken, service manual gives part number 1-571-277-11 (Sony specific probably),maybe someone seen something similar?

author: Gyro
author_rank: Super Contributor
timestamp: June 21, 2019, 08:49:43 am
content: It's almost certainly a Sony custom part with a product specific contact arrangement.I can't see exactly what the failure is (it all looks pretty mangled / melted). Your best bet is probably try to carefully repair it with epoxy, strips of something rigid etc. and carve away the melted plastic.Either that or find a broken donor unit and very carefully transplant the switch.

author: S0N1C
author_rank: Newbie
timestamp: June 21, 2019, 01:03:45 pm
content: The nub which protrude from switch is broken off, I tried to transplant it from a good one but it broke off on the first try

author: pinkman
author_rank: Regular Contributor
timestamp: June 21, 2019, 02:05:25 pm
content: You could certainly use a soldering iron or other heat to remove the contacts from the sliding piece. Then take some thin PCB material, cut it to size, cut away copper so that the pattern matches the bottom piece. You would be advised to put epoxy in the grooves where copper is cut out and then sand it flat so the contacts glide smoothly. If possible, I would probably cut the bottom piece out of delrin or something like this and embed the little strip of PCB in it, but it is unclear if there is sufficient room for this. If you broke the contacts, you should be able to find comparable contacts inside an old slide type switch.This would be a couple hours of work, you would really have to love this walkman to do it. Like the way you love an old coffee cup that you continue to use after dropping, breaking to pieces and then glueing it back together. For the second time

author: S0N1C
author_rank: Newbie
timestamp: June 21, 2019, 02:43:50 pm
content: This switch is basically two standard on/on switches placed side by side, so for now I just soldered 2 switches and connected 2 stems together with thin copper plate on which I folded a little nub, this way they both move when force applied to a makeshift nub. But I doubt it will work in a long run, so I'm looking for a more clean and permanent solution.Thank you for ideas!

author: tooki
author_rank: Super Contributor
timestamp: June 21, 2019, 03:04:08 pm
content: I’m in the process of milling a slider for the micro slide switch in an early 90s Sony remote control. The stem snapped off, and it’s just not something where glue would work well. So I’m just reproducing it by carefully milling phenolic board. (I got sidetracked from this and need to go back to it...)
Help finding a driver board for  - Page 1
Forum section: electronics / repair

author: Mica_antenica
author_rank: Newbie
timestamp: July 20, 2025, 08:33:02 pm
content: Hi i have this display panel IVO R140NWF5 R6 from a broken lenovo thinkpad laptop and i would like to reuse it and make a monitor out of it now I cant find anywhere board for it it is a eDP display but ot has also a touch cells on it and it is all one connector the on cell touch uses usb.
Help finding a replacement for, or datasheet of, an obsolete Omron relay? - Page 1
Forum section: electronics / repair

author: cvanc
author_rank: Frequent Contributor
timestamp: May 09, 2019, 04:03:57 am
content: I think this style was called 'flat pack' back in the day? Not 100% sure about that.It's an Omron LZNQ4 with a 24VDC coil. I can't even find a datasheet, much less an available replacement. Photo attached.Any assistance is gratefully appreciated! Thanks.

author: CJay
author_rank: Super Contributor
timestamp: May 09, 2019, 05:27:58 am
content: Panasonic NF4E appears to be equivalent and is also obsolete but appears to be widely available (Farnell link included for datasheet)https://uk.farnell.com/panasonic-electric-works/nf4eb-24v/relay-signal-4pdt-30vdc-2a/dp/1200948

author: plurn
author_rank: Regular Contributor
timestamp: May 09, 2019, 06:17:25 am
content: that is an expensive relay:https://www.chip1stop.com/USA/en/product/detail?partId=MTDK-0006903&mpn=NF4EB-4M-24Vnot sure if that is the right variant of the NF4EBanother option:https://cephosrelays.com/c-nf4eb-relay/might be able to get used ones here?:http://plc.client.jp/list_Omron.htmlhttp://plc.client.jp/https://www.onlinecomponents.com/omron-electronics/lzn4q3uadc24-12053370.htmlhttps://www.onlinecomponents.com/m.e.c.-relays/lzn4usdc24-11956038.htmlhttps://www.onlinecomponents.com/m.e.c.-relays/lzn4q3uadc24-11956041.htmldiy substitute:https://www.lz5zm.com/replacement-of-rl1-lzn4-omron-relay-in-ts-830s/would need to change to 24V equivalent relayshttps://www.k4eaa.com/parts.htm"RL-1 REPLACEMENT RELAYTS-530 TS-830Finally! The long awaited K4EAA relay module that replaces the now obsolete NF4EB-12V and Omron parts. ..."for that you would have to plug in 24V equivalentshttp://www.derf.com/search/?part=NF4EB&Submit1=http://www.derf.com/search/?part=LZNQ4&Submit1=available but not much details - eg voltage?

author: CJay
author_rank: Super Contributor
timestamp: May 09, 2019, 09:13:22 am
content: The Panasonic one (try National as a search term) can be had for £10 from some places

author: daedalux
author_rank: Contributor
timestamp: May 09, 2019, 09:09:53 pm
content: It's usually not very difficult to replace an unobtainable relay with one with the same coil rating and number of circuits using rigid wire and placing it upside down. The protoboard wire will usually do the trick for small signal. By making this you can consider using a sealed, higher quality relay, or whatever.
Help finding company logo on this SMD.  - Page 1
Forum section: electronics / repair

author: iRepairElectronics
author_rank: Contributor
timestamp: October 01, 2021, 05:28:30 pm
content: Im trying to find What company logo this is. the part is in the power circuit area. the unit is not powering on.its a teradek 4k reciever in case you need to know.I measure 145k either way across them. i suspect these could be a fuse of some sort.the people that use these items are notorious for reversing polarity on power cables going in.https://postimg.cc/G9Ghwmjr]https://i.postimg.cc/T2HybyLy/IMG-5259.jpg

author: Twoflower
author_rank: Frequent Contributor
timestamp: October 01, 2021, 05:54:39 pm
content: That logo is Diodes Inc. Strangely it seems to miss the cathode marking. If I'm not mistaken this matches the marking:https://www.diodes.com/assets/Datasheets/ds19005.pdf-> SMAJ33(C)A (Page 3; look for VM)

author: Nusa
author_rank: Super Contributor
timestamp: October 01, 2021, 06:10:23 pm
content: There's no cathode band because it's the bidirectional version.

author: iRepairElectronics
author_rank: Contributor
timestamp: October 01, 2021, 06:12:10 pm
content: WOW Excellent catch. that looks like the bugger.

author: Twoflower
author_rank: Frequent Contributor
timestamp: October 01, 2021, 06:22:55 pm
content: Quote from: Nusa on October 01, 2021, 06:10:23 pmAh, thanks. That explains the missing mark. I was missing that as I just did a short check. But the Column indeed denotes the VM-Type as bidi. They should also give a hint at the marking drawing.

author: LateLesley
author_rank: Frequent Contributor
timestamp: October 01, 2021, 07:36:17 pm
content: Just for future reference, here's a link for you to bookmark, which might come in handy to identify stuff. It's not got everything, but it has a lot.http://www.ecadata.de/herst/myshowlogo.php?F_SPRACHE=2

author: DavidAlfa
author_rank: Super Contributor
timestamp: October 01, 2021, 07:54:04 pm
content: Very nice contribution!There're companies that seem to do it badly on purpose!Ex. Rectron:- Hey, let's make a diode logo, one of the most the most common semiconductors, so people search us in google like "diode logo company"
Removed - Page 1
Forum section: electronics / repair

author: Caliaxy
author_rank: Frequent Contributor
timestamp: November 04, 2019, 01:26:47 pm
content: 2SK841?

author: mariush
author_rank: Super Contributor
timestamp: November 04, 2019, 01:45:36 pm
content: The SK makes me think it's made by Sanken , a Japanese company.It could be Sanken TM841 (based on M841 printed on it) :sanken-tm841.pdf(64.14 kB - downloaded 142 times.)
Help finding new potentiometer  - Page 1
Forum section: electronics / repair

author: .....
author_rank: Contributor
timestamp: February 12, 2020, 08:05:00 pm
content: Hi everyonei am trying to source a new pot for a compressor as i accidentally broke it when i tried to remove the knob for cleaningi am having trouble finding a suitable replacementa rough specssize: mini potshaft shape: D shapeshaft length: about 25mmany help is much appreciatedJack

author: andy3055
author_rank: Super Contributor
timestamp: February 12, 2020, 09:35:41 pm
content: This might be suitable. Check on the UK RS site:https://americas.rsdelivers.com/product/te-connectivity/1623767-2/te-connectivity-1-gang-rotary-carbon/0168207

author: .....
author_rank: Contributor
timestamp: February 12, 2020, 10:07:18 pm
content: thanks for the replyunfortunately after checking the measurements of that with the broken pot it is slightly to bigthanksjack

author: andy3055
author_rank: Super Contributor
timestamp: February 13, 2020, 04:04:54 am
content: Try this:https://www.youdoitelectronics.com/philmore-1meg-ohm-mini-linear-taper-potentiometer-pc78

author: .....
author_rank: Contributor
timestamp: February 14, 2020, 08:15:19 pm
content: that one looks perfectthanks for the helpJack
Help finding odd capacitors? - Page 1
Forum section: electronics / repair

author: AndrewM
author_rank: Contributor
timestamp: May 09, 2019, 12:19:21 am
content: Hi,I'm looking for a motor capacitor for a ceiling fan.See:I haven't been able to find that big 2x4.5uF capacitor anywhere. I can find ones like this (https://www.aliexpress.com/item/32888027115.html?productId=32888027115&productSubject=CBB61-1UF-1-2UF-1-5UF-2UF-2-5UF-3UF-3-5UF-4UF-4-5UF-starting) or similar ones with 5 wires.I looked up that UL E number and foundhttps://iq.ulprospector.com/en/profile?e=20662- but I can't find any dual capacitors matching the capacitance and dimensions the manufacturer's website (http://en.shengye.com/products.aspx?TypeId=67&FId=t3:67:3), let alone on ebay, aliexpress, etc...Any suggestions on where else I should look? I might be able to use two of those CB61 4.5uF capacitors if I cut a hole in the plastic box that holds the fan motor circuit.Thanks!

author: TERRA Operative
author_rank: Super Contributor
timestamp: May 09, 2019, 01:50:14 am
content: You can just use two separate capacitors wired as in the schematic on the side of the old one.Two appropriately rated film caps, a bit of solder, a bit of heat shrink and it'll work fine.

author: tautech
author_rank: Super Contributor
timestamp: May 09, 2019, 01:51:56 am
content: Yep look here:https://www.aliexpress.com/wholesale?spm=2114.search0104.9.3.5cb41e12TNFsLx&initiative_id=QRW_20190508184954&SearchText=electric+fan+capacitor
Help finding potentiometer! - Page 1
Forum section: electronics / repair

author: mikec
author_rank: Contributor
timestamp: October 18, 2021, 10:57:53 pm
content: Hi,Got some repairs to do to a board where I am confident the potentiometers have been damaged over time. I am having a lot of trouble trying to findexact replacements. The form factor is pretty common, just some of the dimensions (thread height, base height and knob holder height combination) areproving to be tricky. Would appreciate any help, the pictures attached provide dimensions and an actual part number (which hasn't help me at all), its a 1Kohm<100%-full-turn potentiometer!

author: mikec
author_rank: Contributor
timestamp: October 18, 2021, 11:05:59 pm
content: I should have posted my search results so far:This is the closest i've come, thread height and knob-holder height are ok (would be good enough), base height unknown here.. knob-holder dimensions are good and it also has the keying.BUT besides that I don't speak french, I have no intention of spending 70euro on a 1Kohm potentiometer, I've bought potentiometers from the same family as this for 10euro which is more then enough for the job these have in the application.https://www.amazon.fr/Jgzwlkj-Potentiom%C3%A8tre-Rotatif-Vishay-potentiom%C3%A8tre/dp/B09JFXBR7KThe next one I have seen plenty of, but the dimensions just won't work for mehttps://en.aliradar.com/item/32832315125-2pcs-lot-alps-alps-rk09l-precision-potentiometer-single-b50k-axis-long-20mm-power-amplifier-potentiometer

author: fzabkar
author_rank: Super Contributor
timestamp: October 19, 2021, 12:18:32 am
content: It probably doesn't help, but the original pot appears to have been manufactured by Clarostat / Honeywell.https://www.goldmine-elec-products.com/images/G20608B.jpghttps://www.electronicsurplus.com/clarostat-cl-212554-potentiometer-20k-ohm-spdt-switchI had a look at the Wayback Machine, but I get the feeling that yours is a custom part.https://web.archive.org/web/2017*/clarostat.com

author: Audiorepair
author_rank: Frequent Contributor
timestamp: October 19, 2021, 07:03:06 am
content: Neve and SSL used Clarostat pots in their mixing desks, and as such these are also still sought after as lots of these are still in service.So searching in that world may throw up something.https://www.studioelectronics.biz/sunshop/index.php?l=product_detail&p=4272

author: perieanuo
author_rank: Frequent Contributor
timestamp: October 19, 2021, 07:10:33 am
content: hi,in those cases i struggle to find mainstream components and adapt them to that old device, potentiometers are usually simple to adapt with some new fancy button, maybe the hole adjusted and game on.maybe you want do some pro restoration
Help finding replacement 2pin DC rectangular notched plug - Page 1
Forum section: electronics / repair

author: mdronic
author_rank: Contributor
timestamp: April 16, 2021, 09:48:40 am
content: I don't seem to be able to find a replacement 2pin DC rectangular notched plug for a switch mode 12v 5a. This is for a 12v thermoelectric cooler/warmer running on 240v. Several people seem to be trying to find them as well without success. I can find plenty of leads with the plug but don't want to have to pay for whole lead to cut up for plug. They seem to also be called "car cooler plugs". Image of switch mode, lead with plug, and reference socket museums. Any help greatly appreciated.

author: coromonadalix
author_rank: Super Contributor
timestamp: April 16, 2021, 02:33:08 pm
content: you have thoses with rounded edges with a notch who can connect in the rectangular plugsomething like IEC 320 C8 orhttps://www.gamestop.com/electronics/accessories/cables-interconnects/products/2-pin-connector-ac-power-cord-6-ft/11099675.htmlI think it's called the C7 connector, for the two rounded sidesI know there is a model with one square side too, used a lot in the Sony stuff, i did had in the past an electrical item with your needed plug, searched tons of vintage ac connectors, nothing came up like yours

author: coromonadalix
author_rank: Super Contributor
timestamp: April 17, 2021, 01:41:14 am
content: or this one ??https://www.etsy.com/au/listing/622977541/vintage-power-cord-for-salton-hotrayUse a dremel to carve the needed notch ??

author: coromonadalix
author_rank: Super Contributor
timestamp: April 17, 2021, 01:49:50 am
content: Maybe this one on Ebayhttps://www.ebay.ca/itm/Vintage-Tandy-AC-Power-Cord-2-Prong-With-Notch-Non-Polarized/224179246975?hash=item34321fd77f:g:LCAAAOSwZmpfd9jASeems the right one ?? just mod it with an 12vdc car plug on the other end ??

author: AlexanderB
author_rank: Newbie
timestamp: April 19, 2021, 12:58:42 pm
content: https://aliexpress.com/item/33035313469.htmlRandom/first result on Ali.Vintage? Nah, just the power plug that literally all the mini TEC fridges use.
Help finding replacement Caps for Cambridge Amp - Page 1
Forum section: electronics / repair

author: secondlife
author_rank: Newbie
timestamp: November 18, 2021, 01:42:04 am
content: Hi all. I've been working to repair a Cambridge amplifier where the two power caps were blown, the caps are made by Cambridge and are rated at 71 volts, 1500uf. These puppy's are unfortunately proving really difficult to find, Cambridge spare parts advised they long ago changed to lower voltage caps and don't have stock. Likewise, checking the major suppliers online for third party options there is nothing much out there even at high voltages. I guess the option exists to look at non audio grade caps, or take a punt on AliExpress but I would prefer not to go down that route if possible. Does anyone have any ideas on other options to hunt down these parts?Photo attached for reference.

author: CaptDon
author_rank: Super Contributor
timestamp: November 18, 2021, 04:03:20 am
content: Forget the "Special audio grade" crap. At 15,000uf any computer grade capacitor will work. Basically you should easily find perhaps 20,000uf @ 75v or maybe even 100v which will work just dandy. Cambridge didn't make that cap in house and surely who ever did make it didn't adjust their manufacturing process to make the capacitor 'audio grade'. Years ago big electrolytics were manufactured as 'Computer Grade'. That mainly indicated they could withstand huge ripple currents that were common in low voltage high amperage linear computer power supplies. Applying 'Audio Grade' to the label allows Audiophools to wet their pants and pull bigger denominations of currency from their wallets.

author: secondlife
author_rank: Newbie
timestamp: November 18, 2021, 04:22:22 am
content: Terrific reply, got a laugh out of me 😂Just confirming that it was 1500 not 15000. Not that it makes any difference based on your general advise

author: bdunham7
author_rank: Super Contributor
timestamp: November 18, 2021, 04:31:04 am
content: Is there a physical space issue that would make it difficult to put in a slightly larger (diameter or height) unit? What type of terminals? Typically you would just find a 15,000uF 100V unit and replace it with that, but I've seen those 71V versions used in some pretty tight spots. For example this would work well if it fits:https://www.mouser.com/ProductDetail/Cornell-Dubilier/383LX153M080N082?qs=sGAEpiMZZMtJbfcMcIM8CKB0F0QNHHNsMf6i9osmULo%3D
Help finding replacement OVP IC - Page 1
Forum section: electronics / repair

author: ImpulsiveJames
author_rank: Contributor
timestamp: June 22, 2024, 06:04:16 am
content: I was replacing a button on my wireless gaming controller (Gulikit) and accidentally murdered a poor SOT23 over voltage protection IC. It's a P14C13 and looks like it's made by Prisemi. I'm having trouble finding a data sheet, but more importantly, does mouser or digikey call these things something other than a Over Voltage Protection IC? If someone can help with a datasheet or replacement ideas, that would be awesome. I'm pretty sure it's just for a standard USBC charger with a 1S cell, but I've been wrong before

author: indeterminate
author_rank: Regular Contributor
timestamp: June 22, 2024, 06:33:48 am
content: Have a look under TVS Transient Voltage Suppressorshttps://www.digikey.com/en/products/filter/transient-voltage-suppressors-tvs/tvs-diodes/144

author: fzabkar
author_rank: Super Contributor
timestamp: June 22, 2024, 03:35:48 pm
content: https://www.prisemi.com/pdf/2ovpgybhqx/P14C13.pdfhttps://www.prisemi.com/en/product/pa2/

author: ImpulsiveJames
author_rank: Contributor
timestamp: June 22, 2024, 07:33:28 pm
content: Huge help everyone thanks!I couldn't find much from the TVS search, but I'll keep looking

author: fzabkar
author_rank: Super Contributor
timestamp: June 22, 2024, 07:55:16 pm
content: Quote from: ImpulsiveJames on June 22, 2024, 07:33:28 pmStop looking for TVS devices. Instead, look for an electronic fuse or a current-limited load switch.

author: fzabkar
author_rank: Super Contributor
timestamp: June 23, 2024, 03:08:33 pm
content: If you want to run your device without OVP, you can bridge the Vin and Vout pins.
Help finding schematic of Korean amplifier Seoum SA-4130 (Tanol/Straut KA-4130) - Page 1
Forum section: electronics / repair

author: samnmax
author_rank: Regular Contributor
timestamp: October 05, 2021, 06:51:26 am
content: Hi,I'm looking for the schematic of a Korean amplifier from the late 70's/early 80's. It was sold in Spain as Tanol KA-4130, but originally it's a Seoum SA-4130.Also sold as Straut KA-4130, Siemens RV-630.Some general info I found:http://www.hifi-archiv.info/Voelkner/1983-84/8384_0275.jpeghttp://tsf-schoser.e-monsite.com/pages/restaurations-mai-2013/amplificateur-stereo-sa-4130-seoum.htmlIt seems there's also a 4130B which is a slimmer version with a different circuit.This one is a discrete transistor amplifier with a pair of D586+D616 per channel.I managed to burn some components when the voltmeter probe slipped. I changed R129 and some shorted transistors, (I know, the ebay ones may be counterfeit).Now it seems it only amplifies the top part of the sine wave, and only when I turn on the source, afterwards the output wave diminishes a bit. Both channels behave similarly. I'm reverse engineering the schematic, but it's a bit complicated.Thank you!

author: pmh_9@hotmail.com
author_rank: Newbie
timestamp: November 04, 2021, 07:48:01 pm
content: Hello! i have this same amp. Produces distortion at low volume but not at high volume.With headphones it sounds great but as soon as you connect an 8 ohm load, it distorts in the channel where it is, including headphones.I changed the four main transistors and nothing ... they usually get 0.4V instead of 0.7V that they should be, so the problem will be with the power supply. I have also changed almost all the capacitors and it remains the same ...Any clues ??, does anyone have the service manual ??I'm going crazy without him ...Thanks!!
Repairing Emporia Vue Gen 2 energy monitor.Help finding what pmic chip this is.  - Page 1
Forum section: electronics / repair

author: Fflint
author_rank: Frequent Contributor
timestamp: June 23, 2024, 09:26:51 am
content: I'm trying to repair an energy monitor. An Emporia Vue gen 2 that was hooked up with neutral and phase 3 reversed. Two MOVs blew up and this Pmic in a soic8 case.Unfortunately the markings turn nothing in Google. Looking through the microscope it looks like the first letter is P but other photos of the product show same chip with other marking starting with 8.Here is the broken one:And here is another photo from the web:It seems pins 5 to 8 are connected together to the transformer and through a diode and resistor to another pin on the transformer (same winding?) Marking on my chip is:PGFDSA or BGFDSAThe one in another picture has marking:BGFCN8Can anyone help?That is all the clue I have :-(

author: Fflint
author_rank: Frequent Contributor
timestamp: June 23, 2024, 09:46:55 am
content: There is also this internal structure from a reverse engineered schematic:If anyone knows an equivalent ic that would be great. Even if the pinout is different I could bodge-wire it.

author: Fflint
author_rank: Frequent Contributor
timestamp: June 23, 2024, 01:12:10 pm
content: After hooking it up to 5V on the logic side it connects to WiFi, logs into its cloud account and makes all the right sounds and noises. But measurements through CTs all come as zeros.I checked all voltages are present, but I can't figure out how to test if the right measurement signal is present.Here is the schematic of where the CT is plugged in:It is connected to what looks like an analog multiplexer and into a Mcu with an ADC. However despite varying the current the CT is supposed to measure I get 1.8V on output. Nothing else. (viewed with an oscilloscope).The CT has very low resistance of 19ohm so trying to use it with the usual burden resistor of few hundred ohms doesn't work. I tried with 20 ohm, but I thing all i saw was 50hz buzz getting picked up.Is anyone here familiar with such measurement circuits?

author: fzabkar
author_rank: Super Contributor
timestamp: June 23, 2024, 05:16:22 pm
content: You might have better luck finding it if you were to search for "flyback converter" or "flyback regulator".Also, your U1 pinouts don't seem to be correct. Pin #1 looks like Vcc, and pin #4 looks like current sense, and pin #2 seems to be ground.

author: fmashockie
author_rank: Frequent Contributor
timestamp: June 24, 2024, 02:04:57 pm
content: I agree with Fzabkar. The reverse engineered schematic you have clearly isn't drawn correctly. I would try tracing it out yourself because this is just going to throw you off.I would also try searching for SOIC-8 AC/DC converters on Mouser/Digikey once you have the schematic drawn out correctly. The more you can do, the better. It clearly has a built in MOSFET. Maybe pin 1 is an internal Bypass pin or Vcc.Good luck!
Help fixing Panasonic TNPA5808 low voltage issue - Page 1
Forum section: electronics / repair

author: madhushankarox
author_rank: Newbie
timestamp: February 28, 2024, 07:25:37 am
content: I'm trying to fix an old Panasonic LED TV, mainly for educational purposes.While I was checking voltages on the P-Board I got to know the voltage of the SRV-16V rail is 13.2V (with and without dummy load).Both 16V and 24V rails are bit lower than specifications. However the 5.3V standby line is good.I have tested diodes, transistors and some other parts and didn't find any issue. This seems beyond my knowledge.Please help me to solve this issue. ThanksPS: Schematics is attached.

author: m k
author_rank: Super Contributor
timestamp: March 09, 2024, 02:05:20 pm
content: 16V is adjusted, 24V is following.5V has its own regulator.You can start checking the reference diode IC7501 and its connections.
Help Fixing whining Noise from drivers in speaker - Page 1
Forum section: electronics / repair

author: selfrepaircare
author_rank: Newbie
timestamp: July 31, 2019, 03:23:35 am
content: I got a hold of these bluetooth speakers but when powered on, there's a constant high pitched noise. I tried digging online for a fix and what I did find was info on ground loops but I don't have the speaker plugged in (it has a battery) and I don't see anything out of the norm on the inside.Besides the whining these are decent speakers that I'd hate to throw out. I did some trial and error to narrow down what's causing the whining by unplugging the internal connectors of the battery, DC connector, and the speakers, while flipping it on when each was unplugged and I believe that its definitely being caused by the drivers.Does anyone know what the problem could be or a potential solution?Here are some pictures of the internals:

author: oPossum
author_rank: Super Contributor
timestamp: July 31, 2019, 03:34:38 am
content: Could be a cheap filterless class D amp chip. Hissing is somewhat normal for them.
Help Fluke 8845 can't read resistance value - Page 1
Forum section: electronics / repair

author: qnhn90
author_rank: Contributor
timestamp: January 13, 2021, 02:37:44 am
content: hi alli have 1 ea fluke 8845 can't read resistance value.Do you have a way to handle it thoroughly?I can only measure up to 170k ohm.and then other higher values ​​cannot be measured.

author: bdunham7
author_rank: Super Contributor
timestamp: January 13, 2021, 02:52:25 am
content: Are you saying that it reads **accurately** up to 170K, but then displays 'OVERLOAD' for anything higher than that? Or is it inaccurate?

author: qnhn90
author_rank: Contributor
timestamp: January 13, 2021, 09:54:05 am
content: If the value is higher, it is still only displayed at 170k ohm. no more.

author: Kleinstein
author_rank: Super Contributor
timestamp: January 13, 2021, 10:00:30 am
content: Is the 170 K upper limit fixed, independent of the range (e.g. 2 M or 20 M range) ?It could be something like the Ohms current source not able to provide a higher voltage or some additional resistance across the inputs (e.g. a bad MOV, bad Ohms source protection circuit, dirty board (leaking cap, fried bug).A test worth while may be checking if the voltage reading input is also high impedance as it should. One can do this by charging a small cap (like 1-10 n) to some 10 V and than check how fast the capacitors discharges when measuring the voltage.

author: bdunham7
author_rank: Super Contributor
timestamp: January 13, 2021, 02:48:17 pm
content: Quote from: qnhn90 on January 13, 2021, 09:54:05 amOK, I assume this is on the 1 megohm range. First, try manually putting it in the 10 megohm range and see what the reading is for a larger resistor. Then use another meter with at least a 10M input impedance and measure the voltage output of the 8845A in the 1M and 10M resistance ranges.Have you had the meter for a while and this all suddenly just happened or did you get it with this problem?

author: wn1fju
author_rank: Frequent Contributor
timestamp: January 13, 2021, 06:19:16 pm
content: I've had several "broken" meters (not this particular Fluke model) that behaved strangely. Finding nothing overtly wrong with the circuitry, I ran through the calibrationprocedure and things then worked fine. It seems that a lot of times, the calibration constants get corrupted and the meter will produce erroneous results until they areoverwritten with values that make sense.

author: mzacharias
author_rank: Frequent Contributor
timestamp: January 14, 2021, 12:21:29 am
content: I would use another multimeter to measure the input resistance of the Fluke on its DC volts mode.I'm betting a damaged part in the front end, coincidentally measuring - wait for it - 170K
Help for a Crystal/Oscillators identification please  - Page 1
Forum section: electronics / repair

author: IFIXIT
author_rank: Newbie
timestamp: February 23, 2021, 06:41:21 am
content: anyone can help me to find value for this Crystal/Oscillators please ?number on thecomponent:3000 410HBC419:k2 pin GNDmany thanks

author: Gominalo
author_rank: Contributor
timestamp: February 23, 2021, 09:51:57 am
content: Hi, I´m not 100% but seems to be a programmable clock generator from silicon labs.https://www.silabs.com/documents/public/data-sheets/si570.pdfI searched in digikey for HBC and filtered for 8-SMD.Hope i helped you.

author: fzabkar
author_rank: Super Contributor
timestamp: February 24, 2021, 03:05:11 am
content: I'm guessing it's a 30MHz oscillator. Either 419 or 410 appears to be a YWW date code (2004 or 2014, week 10 or 19). The date codes on the other ICs may provide a reference.Maybe the "4" in "410" is a multiplier, ie 3000 x 10^4 HzIt might help if you could measure its Vcc.

author: IFIXIT
author_rank: Newbie
timestamp: February 26, 2021, 07:22:19 am
content: Hiits a Coaster Pagers for a Restaurant and can't be replaced easily.i found some damage on that Crystal but i already clean it and put it back but still no communication between receiver and pager.receiver have Crystal too with this part number : 30/10NK

author: fzabkar
author_rank: Super Contributor
timestamp: February 26, 2021, 07:06:23 pm
content: It appears to be a 30MHz crystal, not an oscillator.https://www.silabs.com/documents/public/data-sheets/Si4330.pdfQuote
HELP HP3468A ERROR - Page 1
Forum section: electronics / repair

author: Kidon
author_rank: Regular Contributor
timestamp: January 22, 2022, 10:03:12 am
content: Hi everyone,Upon turning on my HP3468A I keep getting “A-D ERROR 8”. Does anyone know what that is and how to fix it?I can’t find anything about it.Thank you

author: Kidon
author_rank: Regular Contributor
timestamp: January 22, 2022, 10:26:39 am
content: I’m sorry,Ignore my previous post. After about 10 times showing me that error message, it just suddenly disappeared.Go figure…
Help |  HW-USBN-2B LATTICE - Page 1
Forum section: electronics / repair

author: Ronikg4
author_rank: Newbie
timestamp: October 11, 2021, 08:04:40 am
content: Hey everybody ,For some reason , my lattice programmer, d9 diode on board was burn ,does anyone know her part number?

author: fzabkar
author_rank: Super Contributor
timestamp: October 11, 2021, 06:04:16 pm
content: Those diodes look like protection diodes, perhaps a TVS diode and a Schottky rectifier in parallel. If so, and if the fuse is OK, then the board should work without the diodes.

author: Ronikg4
author_rank: Newbie
timestamp: October 11, 2021, 06:22:59 pm
content: Ohhh you maybe right, ill cheak the fuze
Help I.D. this vendor logo? - Page 1
Forum section: electronics / repair

author: cvanc
author_rank: Frequent Contributor
timestamp: July 10, 2019, 12:53:13 pm
content: Anybody recognize this vendor? If yes, any opinions on good/bad/somewhere in between? Thanks.

author: Psi
author_rank: Super Contributor
timestamp: July 10, 2019, 01:24:38 pm
content: Looks a bit like CIOEI had a look around but couldn't find anything.Maybe someone else will have more luck.

author: TurboTom
author_rank: Super Contributor
timestamp: July 10, 2019, 09:42:20 pm
content: The company is ECI (Electronic Concepts Inc).
help , I need a system image file to recover  TDS5054 - Page 1
Forum section: electronics / repair

author: 大天使
author_rank: Newbie
timestamp: April 28, 2021, 12:06:34 pm
content: I accidentally broke the system. Now I need a system image file to recover my machine.the system is windows METhe model is Tek tds5054. Thank youemail:55860061@qq.com

author: 大天使
author_rank: Newbie
timestamp: April 30, 2021, 05:14:26 am
content: The problem is solved, and the process is complicated. Use the CD to restore the system, everything looks very normal, thank you。

author: BrunoGelli
author_rank: Contributor
timestamp: May 30, 2022, 08:27:34 pm
content: Hi,Can you share the OS with me? I'm trying to revive one TDS5054, but the restoration CD is long gone.Thanks!Bruno
Help ID component.  - Page 1
Forum section: electronics / repair

author: SCAR17s
author_rank: Newbie
timestamp: May 08, 2022, 05:23:31 pm
content: Came across these on a rs232 interface, would like to find a part#! most of the chips are dated 96~99 if that helps.

author: SCAR17s
author_rank: Newbie
timestamp: May 08, 2022, 05:27:44 pm
content: also, check out these guys on the +12v input.

author: ataradov
author_rank: Super Contributor
timestamp: May 08, 2022, 05:43:03 pm
content: Parts on the power supply are commonly known as "3 terminal capacitor". They are like a an LC filter.RS232 may be similar, since they also appear to have 3 terminals and the use would match.Exact part numbers would be hard to tell.

author: SCAR17s
author_rank: Newbie
timestamp: May 08, 2022, 05:56:22 pm
content: You are brilliant!https://www.murata.com/en-global/products/emc/emifil/overview/lineup/chip

author: fzabkar
author_rank: Super Contributor
timestamp: May 08, 2022, 07:45:45 pm
content: http://www.ferroperm.com/?id=151&c=All-Filters
Help ID SMD chip from the 80's - DB 139? - Page 1
Forum section: electronics / repair

author: gmc
author_rank: Regular Contributor
timestamp: October 30, 2022, 03:24:28 pm
content: I've got a PSU from a IBM 5160 I'm trying to repair. There does not seem to be schematic so I'm reverse engineering it.The PSU has a daughter board on in which I think checks for overvoltage / excess current etc and then shuts down the PSU.There is a SMD chip (Yes, this surprised me - the PSU is from the early 80's) with the identifiers:DB 13933414 pinThe chip is manufactured by Thomson CSF

author: Andy Watson
author_rank: Super Contributor
timestamp: October 30, 2022, 04:01:34 pm
content: Could they be quad comparators? AKA LM139

author: DavidAlfa
author_rank: Super Contributor
timestamp: October 30, 2022, 04:09:11 pm
content: This is the most complete electronics logo list I'm aware of.It will look like crap if using mobile, enable "Computer View".https://how-to.fandom.com/wiki/How_to_identify_integrated_circuit_(chip)_manufacturers_by_their_logos/A-E

author: gmc
author_rank: Regular Contributor
timestamp: October 30, 2022, 04:16:53 pm
content: I think I've tracked it down. It's a TDB0139.The LM139 / 339 is supposed to be the equiivalent, which is a quad comparitor.
Help Identify a Part - Page 1
Forum section: electronics / repair

author: bettabowls
author_rank: Newbie
timestamp: July 13, 2023, 08:55:14 pm
content: Can someone help me identify what this is. I'm guessing it's a fuse. It's markings are SE7 049

author: madires
author_rank: Super Contributor
timestamp: July 13, 2023, 09:17:15 pm
content: Yep, it's a thermal fuse.

author: bettabowls
author_rank: Newbie
timestamp: July 13, 2023, 11:07:10 pm
content: Thank you!Is there anyway to check it's value? There's no markings on the unit. Also, the box it was in caught on fire and the fuse is covered in soot.

author: fzabkar
author_rank: Super Contributor
timestamp: July 14, 2023, 12:09:59 am
content: "049" could be a YWW (Year/Week) date code. Comparing it against the markings on other components should help to confirm this.

author: madires
author_rank: Super Contributor
timestamp: July 14, 2023, 11:36:49 am
content: Based on the size I'd guess its max current is roughly 1-3 A. And ESKA's E series (similar package) has also a one digit identifier for the temperature (E 7: 150 °C).

author: bettabowls
author_rank: Newbie
timestamp: July 14, 2023, 02:08:42 pm
content: It provides circuit protection for a 277 V AC light. Is 1 - 3 amps too low?

author: madires
author_rank: Super Contributor
timestamp: July 14, 2023, 04:05:24 pm
content: How much current does the light need?

author: bettabowls
author_rank: Newbie
timestamp: July 14, 2023, 05:10:38 pm
content: Looks like the ballast the drives the LEDs needs 630 mA. So I guess 1 - 3 amps would work!

author: madires
author_rank: Super Contributor
timestamp: July 14, 2023, 05:55:47 pm
content: If the blue disc-shaped components are MOVs then the thermal fuse should be their thermal protection. So 2-3A and 125 or 150°C might be fine. Also replace the MOVs in case they look too smoked.

author: bettabowls
author_rank: Newbie
timestamp: July 14, 2023, 06:07:23 pm
content: Yes! Ordering new MOVs too, thank you! Pretty much everything but the PCB will be replaced.
Help identify an AEG diode - Page 1
Forum section: electronics / repair

author: mairo
author_rank: Unknown
timestamp: December 09, 2021, 12:25:29 am
content: Hi all, can some one help me identify an AEG diode specs so I can get an alternative. The marking on the diode are: AEG D24N 400 U 23S7 GThank you

author: fzabkar
author_rank: Super Contributor
timestamp: December 09, 2021, 12:46:49 am
content: My searches for similar diodes would suggest that it is a 24A, 400V diode.For example, a T24N 800 is a 24A 800V diode.https://datasheet.datasheetarchive.com/originals/scans/Scans-007/Scans-00148833.pdf

author: mag_therm
author_rank: Frequent Contributor
timestamp: December 09, 2021, 01:48:00 am
content: If M6 threaded stud, probably similar to Semikron SKN20/04N : Anode to StudR : Cathode to Stud
Help Identify another Fan Control IC - Page 1
Forum section: electronics / repair

author: Harimake
author_rank: Contributor
timestamp: January 06, 2022, 04:30:54 pm
content: I just ran into another fan control circuit I don't recognize.It's a 5V DC fan, but it gets +12v DC power from the positive leg of the power supply.Looks like the ground is going through an IC of some sort. I have two units with different markings for the IC: JC1A or I(or J or L)1ASOT-23 package.Pin 1 of the IC goes into a GPIO pin on the PSOC4 over a 2.2k 1% resistor.Pin 2 goes to a PSOC4 VSS.Pin 3 connects to the fan motor and a 100uF 25V radial capacitor.The fan only turns on when I apply heat to the SOT-23 IC (or in that general area). And when it does, I only see about 3V on the fan power pins, which is normal.My initial thought was that it's just a simple fet and they control voltage to the fan with a PWM from the PSOC4.But it doesn't seem to be the case as the fan only turns on when the heat is applied to the IC. Which makes me think that it might be a thermistor circuit of some kind.Please point me in the right direction. Thank you!

author: fzabkar
author_rank: Super Contributor
timestamp: January 06, 2022, 06:22:12 pm
content: I would think that a P-channel MOSFET or PNP transistor would be a likely fit, although capacitor C1 seems to contradict this.

author: Harimake
author_rank: Contributor
timestamp: January 06, 2022, 07:21:39 pm
content: C1 throws me off also. When I measure voltages on a working unit, I get about 3V across the fan pins and about 9 volts across C1. When the fan is off, I get 12v across C1 and 0v across the fan.What about an NPN darlington transistor being the mystery sot-23? then the 2.2k resistor directly to the base makes more sense.

author: abdulbadii
author_rank: Frequent Contributor
timestamp: January 06, 2022, 11:55:59 pm
content: Sure there's no R or thermistor etc. around low side, as it'd apply 12V on 5V M ?

author: fzabkar
author_rank: Super Contributor
timestamp: January 07, 2022, 12:46:19 am
content: If the transistor is being PWM-ed, then it would need to discharge the relatively massive capacitor every time it was switched on.That said, I can't see the component as being a linear regulator, as it would need to dissipate 3 times as much power as the fan (9V versus 3V).
Help identify C1B - Page 1
Forum section: electronics / repair

author: jspencerg
author_rank: Regular Contributor
timestamp: May 23, 2022, 12:08:14 am
content: I'm trying to recreate a RF noise generator circuit from the 90's which sorta works now. A four terminal smd component is marked C1B. I've searched through databases suggested in the EEVblog beginner section and have scrolled through pages of google results with no luck. The data sheet would be appreciated.

author: fzabkar
author_rank: Super Contributor
timestamp: May 23, 2022, 12:35:06 am
content: https://www.futurlec.com/Datasheet/Others/UPC1676.pdfhttp://www.smdmark.com/en-US/search/code?id=c1b

author: jspencerg
author_rank: Regular Contributor
timestamp: May 23, 2022, 02:51:08 am
content: Excellent. Thanks very much.
Help, identify chip D05A SOT23-6 - Page 1
Forum section: electronics / repair

author: daisizhou
author_rank: Super Contributor
timestamp: September 17, 2024, 07:44:57 am
content: Hallo everyoneThis is a NEC LCD monitor.After it lights up, it always rolls up and down, it looks like the voltage is unstable.So I tried to replace the capacitor, but I didn't know the specific specifications of the SMD capacitor, so I disassembled the SMD capacitor.The dimensions of the capacitor are 1.6mm x 1.6mm x 3.2mm。I don't know the withstand voltage and capacity of the chip capacitor,A friend suggested that I look for the surrounding circuit components. I took a picture and found a chip with a SOT23-6 package and the code is D05A.It looks like a DCDC voltage conversion circuit.If you know the exact model, please tell me, thanks.

author: fzabkar
author_rank: Super Contributor
timestamp: September 17, 2024, 07:57:43 am
content: Qxxx are transistors.

author: daisizhou
author_rank: Super Contributor
timestamp: September 17, 2024, 08:17:04 am
content: Quote from: fzabkar on September 17, 2024, 07:57:43 amIs it a P-channel MOS tube?

author: fzabkar
author_rank: Super Contributor
timestamp: September 17, 2024, 08:40:38 am
content: Examine the datasheet for the PWM controller IC.

author: daisizhou
author_rank: Super Contributor
timestamp: September 17, 2024, 12:19:02 pm
content: Quote from: fzabkar on September 17, 2024, 08:40:38 amIt seems that the PWM chip should be this oneI found the manual for this monitor, but there is no schematic diagram available

author: fzabkar
author_rank: Super Contributor
timestamp: September 17, 2024, 07:27:00 pm
content: I can't find any information on either IC. I believe D05A is indeed a MOSFET, with the same pinout that you have identified, but I don't know whether it is P-channel.

author: daisizhou
author_rank: Super Contributor
timestamp: September 17, 2024, 07:42:26 pm
content: Quote from: fzabkar on September 17, 2024, 07:27:00 pmA105 1306 TSSOP8 This chip can't find any information

author: gamalot
author_rank: Super Contributor
timestamp: October 03, 2024, 03:54:40 pm
content: Quote from: fzabkar on September 17, 2024, 07:27:00 pmD05A could be AO6400.https://www.aosmd.com/sites/default/files/res/markings/AO6400.pdf
Help identify component - Page 1
Forum section: electronics / repair

author: error21
author_rank: Newbie
timestamp: June 13, 2019, 08:21:38 am
content: Hello,could you please help me identify this 62l 341 compoent?

author: fzabkar
author_rank: Super Contributor
timestamp: June 13, 2019, 08:50:49 am
content: TS4962M, STMicroelectronics, 3 W filter-free class D audio power amplifier, 2.4V - 5.5Vin, marking 62L:https://www.st.com/resource/en/datasheet/ts4962m.pdf

author: error21
author_rank: Newbie
timestamp: June 13, 2019, 08:54:19 am
content: Thank you very much
Help identify component - Page 1
Forum section: electronics / repair

author: 4cx10000
author_rank: Regular Contributor
timestamp: May 27, 2020, 09:00:51 pm
content: Hi!The 3 pin device 817A is one of two located on a small pcb in a plastic housing with a thumb wheel. Very close to these two 817A is a tiny magnet which is rotated by the thumb wheel. Guess, but I am not sure, that it is controlling a proportional valve in an excavator. Anyone out there seen it or know what it is?

author: helius
author_rank: Super Contributor
timestamp: May 27, 2020, 09:05:16 pm
content: www.y-ic.hu/datasheet/a8/HAL817-UT-K.pdf

author: 4cx10000
author_rank: Regular Contributor
timestamp: May 27, 2020, 09:11:33 pm
content: Thanks a lot helius!!Wow you found it! I searched the internet for quiet some time, but to no avail and you found it in a couple of seconds!!Now I will try to search for a distributor that stock them. Thanks again!

author: fzabkar
author_rank: Super Contributor
timestamp: May 27, 2020, 09:36:06 pm
content: The magnet was the clue that the device was a Hall Effect sensor.https://www.google.com/search?q=817a+filetype:pdf+"hall effect"
Help Identify Fan Control IC - Page 1
Forum section: electronics / repair

author: Harimake
author_rank: Contributor
timestamp: October 29, 2021, 02:32:56 pm
content: I'm trying to identify the IC in the Fan control circuit I'm repairing.Markings: CF** (CFC3 in my case)Package: SOT23-5Here's the schematics I was able to RE:

author: Harimake
author_rank: Contributor
timestamp: October 29, 2021, 04:23:14 pm
content: I feel so dumb... earlier I dismissed my initial hunch that this is a voltage regulator of some sort. Now, after doing some more digging, this does look like a 3.3v buck controller using the fet to oscillate. This explains the difference in in/out voltage.Now I have a couple of candidates for a replacement now, but still... which one is the original with CF markings?

author: fzabkar
author_rank: Super Contributor
timestamp: October 29, 2021, 05:51:18 pm
content: To me it looks like an op amp. Q1 is the pass transistor.This part (MCP6001U) has the right marking but wrong pinout (pins 2 and 3 swapped):https://ww1.microchip.com/downloads/en/DeviceDoc/MCP6001-1R-1U-2-4-1-MHz-Low-Power-Op-Amp-DS20001733L.pdf

author: Harimake
author_rank: Contributor
timestamp: October 29, 2021, 06:21:46 pm
content: Quote from: fzabkar on October 29, 2021, 05:51:18 pmI think you are onto something... I forgot about the opamp.The pin numbering in my diagram is not correct, the pins are there to show the physical location on the sot-25 package as I was reversing them. MCP6001U has Vss as the middle pin (#2), which is the GND pin (#3) on my diagram. I think it's a match and makes more sense than a buck controller.

author: fzabkar
author_rank: Super Contributor
timestamp: October 29, 2021, 07:06:15 pm
content: Since your pin numbering is incorrect, I would just like to point out that this chip comes in several different pinouts.

author: Harimake
author_rank: Contributor
timestamp: October 29, 2021, 08:43:41 pm
content: I double checked and the MCP6001U seems to be a perfect match. Thanks again for the suggestion.
Help identify Int'l Rectifier part - Page 1
Forum section: electronics / repair

author: Testtech
author_rank: Regular Contributor
timestamp: July 30, 2019, 11:23:24 pm
content: Need some help identifying an IR part marked:IR P213T6Q6T_F7309 date code I thinkThanks!

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 31, 2019, 12:01:29 am
content: Actually P213T is the date codehttps://www.infineon.com/dgdl/irf7309pbf.pdf?fileId=5546d462533600a4015355f224631b14Tim

author: Testtech
author_rank: Regular Contributor
timestamp: July 31, 2019, 03:15:46 pm
content: DOH! Thanks!