hybridfree/eevblog-posts huggingface dataset:
What can cause an AC adapter to output overvolt ? - Page 1
Forum section: electronics / repair

author: sdancer75
author_rank: Frequent Contributor
timestamp: August 10, 2019, 09:11:24 pm
content: I have an AC adapter from a handheld vacuum cleaner that outputs 28v instead of 18v. What problem can cause this inside the AC adapter and how this can affect the rechargable battery?

author: tunk
author_rank: Super Contributor
timestamp: August 10, 2019, 09:31:26 pm
content: It most likely is a linear power supply without voltage regulation.If that's the case, it is normal. If you load it with 150mA, then thevoltage should be closer to 18V. And if the cells are NiCd or NiMhthen it should be OK.

author: Gyro
author_rank: Super Contributor
timestamp: August 11, 2019, 09:58:59 am
content: Yes, that's a simple unregulated linear psu (transformer+bridge rectifier + smoothing capacitor). The output voltage will drop to 18V at rated load.

author: soldar
author_rank: Super Contributor
timestamp: August 11, 2019, 11:01:46 am
content: Quote from: tunk on August 10, 2019, 09:31:26 pmA linear power supply? No. It would be an unregulated power supply. A linear power supply is one that regulates the output with a transistor or other device in series. This one seems to be unregulated."a linear power supply without voltage regulation" is a contradiction in terms. Like "a burger without the meat".

author: sdancer75
author_rank: Frequent Contributor
timestamp: August 11, 2019, 01:27:41 pm
content: Yes, it seems that it is likely to work just fine under load.I tested this rapidly without load and arbitrarily concluded that it is faulty !!Regards,
What can I use to programme a dsPIC33F? - Page 1
Forum section: electronics / repair

author: perdrix
author_rank: Frequent Contributor
timestamp: May 22, 2020, 01:08:30 pm
content: A telescope mount controller I have to repair drives the motor H-Bridge using a programmed DSPIC33FJ12MC201 IC.So far so good - but one of them has gone badIf I can pry the firmware image out of the supplier - what can I use to programme these babies - neither my Galep-4, nor my Dataman 48XP recognise that the DSPIC33 existsThere's a fix pin socket (0.1" pitch I think) right next to the IC which is clearly intended for programming it with pin 1 to Vpp, 2 to Vcc, 3 to Gnd, 4 to PGD, and 5 to PGC I htinkn these are referred to as PIC ICSP MINI 5 PIN sockets.ThanksDavid

author: jpanhalt
author_rank: Super Contributor
timestamp: May 22, 2020, 01:25:38 pm
content: Most of the Microchip programmers can program and debug that chip:Of course later versions of the same devices can too, like PK4 and ICD4.

author: oPossum
author_rank: Super Contributor
timestamp: May 22, 2020, 01:26:51 pm
content: MPLAB Snaphttps://www.microchip.com/developmenttools/ProductDetails/PartNO/PG164100PICKit 4https://www.microchip.com/developmenttools/ProductDetails/PG164140ICD 4https://www.microchip.com/Developmenttools/ProductDetails/DV164045

author: perdrix
author_rank: Frequent Contributor
timestamp: May 22, 2020, 01:42:24 pm
content: Looks like the PicKit4 is what I need. That ICD4 is a touch too spendy!ThanksDavid

author: NivagSwerdna
author_rank: Super Contributor
timestamp: May 22, 2020, 02:06:06 pm
content: ^ SNAP

author: NivagSwerdna
author_rank: Super Contributor
timestamp: May 22, 2020, 02:15:36 pm
content: Compatibility chart from MPLABX
What component does" TR" used for on power board  - Page 1
Forum section: electronics / repair

author: abdolah
author_rank: Regular Contributor
timestamp: April 14, 2024, 05:28:05 pm
content: Hi guys, hope your day is going wellI was measuring some components on this power supply that was shutting off after a while and the doesn't power on anymore, the component is in the photo below, it looks like a bead firrite, but the text simple is not for that its "TR" , I don't know what is for but the component is measuring high impedanceIf any one know please share itThanks

author: helius
author_rank: Super Contributor
timestamp: April 14, 2024, 07:00:55 pm
content: According to standard nomenclature that is a thermistor.Thermistors (or temperature-dependent resistors) can either increase or decrease their resistance with temperature. These are called PTC and NTC respectively, for positive/negative temperature coefficient. The first type is also sometimes called a posistor.If you test the resistance of the component at room temperature, and then after either heating with heat gun or using cold spray, you should see whether it is PTC or NTC.

author: abdolah
author_rank: Regular Contributor
timestamp: April 15, 2024, 12:54:03 am
content: Thanks for the reply I really appreciate it
What component is this? 8LN4L - Page 1
Forum section: electronics / repair

author: Tony.T
author_rank: Regular Contributor
timestamp: October 12, 2024, 01:10:55 pm
content: What kind of component is this? BFG (8LN4L) Cant find it on internet to order new ones. See picture...marked red..This is a circuitboard from a husqvarna automover charging station.https://www.gardenhirespares.co.uk/media/catalog/product/cache/fcf29b3294734a1494665ec9667b3173/h/v/hv592_89_45_01_2d_0001.jpggot 4 of them. Everyone exactly the same...but 3 of them are shorted and the last one not. (after lightning strike)Thanks in advance....

author: gamalot
author_rank: Super Contributor
timestamp: October 12, 2024, 01:19:50 pm
content: SMCJ30CAhttps://www.littelfuse.com/media?resourcetype=datasheets&itemid=37388813-0d6d-4329-969b-1aa8b7614ac1&filename=littelfuse-tvs-diode-smcj-datasheet

author: Swake
author_rank: Frequent Contributor
timestamp: October 12, 2024, 06:53:55 pm
content: Well, it seems these did their job well!Replace them all 4 at ones, also the one that is not short because it has certainly suffered somewhat too.

author: fzabkar
author_rank: Super Contributor
timestamp: October 12, 2024, 11:03:18 pm
content: http://markingcodes.com/search/c/bfkhttps://ipv4.google.com/search?q=filetype%3Adoc+OR+filetype%3Apdf+%22absolute+maximum%22+bfk
What do Class III/IV Dielectrics, Ceramic Capacitors Look Like? - Page 1
Forum section: electronics / repair

author: helius
author_rank: Super Contributor
timestamp: December 24, 2020, 08:31:45 pm
content: I read that these high-K, barium titanate or "barrier layer effect" capacitors are no longer standardized by the EIA and no longer made. But since they were once made, they could be lurking in old equipment. How do you recognize them?I was unsuccessful in finding any pictures online. Anyone? Bueller?
What does this TVS diode actually do? (DELTA EADP-45AF) - Page 1
Forum section: electronics / repair

author: taoybb
author_rank: Contributor
timestamp: August 20, 2020, 02:00:06 pm
content: Hello, as attached schematic. I'm trying to repair a Acer AL1716 power supply board with 12V rail output only 8V. After some investigate, I found TVS diode code P6KE9.1A (ZD153) is shorted (measured and got 2 ohm). From what I understand, normally TVS would use to clamping between positive and ground rail for surge protection but in this power supply it just clamping between 12V and 5V output. Is it got special purpose? What is behind this design or it's nothing special at all?Also, since I can't find replacement parts here, closet part is P6KE20A which quite large different voltage rating. What can I do with it, Leave it open? or P6KE20A would be fine?
What exactly are complementary matched pair transistors? - Page 1
Forum section: electronics / repair

author: rfengg
author_rank: Regular Contributor
timestamp: February 21, 2023, 02:03:22 am
content: Hi All,Came across the NJW0281G (NPN) and NJW0302G (PNP) transistors from ON Semiconductor in a repair job in which the common data sheet for the complementary pair claims to"NPN/PNP Gain Matching within 10% from 50 mA to 3 A"However what is confusing for me is that , the data sheet also says that hfe can vary everywhere 75 and 150 for any of the 2 devices.....if so, how is this a matched pair?What parameters exactly do you look for when selecting a matched complementary pair if one exists due to the variations in PNP and NPN devices?Do we really have to sit and measure hfe's for many transistor pairs if they have to be used in say, the finals of a audio amp and is there a significant advantage to this especially in terms of distortion for dc coupled amps?Page 4 of the data sheet gives a plot of"NJW0281G Current Gain BandwidthProduct" and "NJW0302G Current Gain BandwidthProduct"which look quite similar, but given the variations of hfe between 75 and 150, how is this guaranteed?

author: M4trix
author_rank: Frequent Contributor
timestamp: February 21, 2023, 02:27:28 am
content: Real matching is done by measuring the Vbe. If the hfe is in the close range, the better. There is an article somewhere on the internetz where Crown audio has explained the difference between matching by Vbe or hfe. If you're building an amp, I wouldn't bother much about matching the PNP with the NPN ones. You won't hear the difference anyway. More important is to match NPN groups and PNP groups.QuoteWell, one would say, matching is not even necessary then. Not true. That's why I always match my transistors.

author: Kleinstein
author_rank: Super Contributor
timestamp: February 21, 2023, 07:51:17 am
content: It depends on the amplifier circuit if NPN to PNP gain matching makes a significant difference. In most circuits it does not make a difference. Usually good designs don't rely on gain matching in the output stage. It is more with the input stage differential pair that VBE and gain (for a pair of same type) matching may be relevant to get a small offset.For the NPN to PNP matching is usually for the gain, if done at all. It is rare to need VBE matching for a NPN/PNP combination.For pair from the same type matching is more often wanted for VBE. For parts from the same batch this usually also leads to reasonable matching of other parameters like the gain and Early voltage.Matching is usually done by measuring the relevant parameter for a set (e.g. 10) of parts and than look in the data for the pairs that are close. It does not need than many parts, as the number of possible pairs goes up like N*(N-1)/2 with the number of parts. As an example it only needs some 25 persons to have a good chance that 2 have the same birthday.
What happens if non isolated power supply replaced with SMPS???? - Page 1
Forum section: electronics / repair

author: Dhanushka
author_rank: Regular Contributor
timestamp: May 26, 2020, 09:01:40 pm
content: Hi,My washing machine is Samsung diamond drum budget(without seven segment display) one. Due to particular reason, the non isolate power supply module(BP5055-12) on the control board was burned. That was generated -12 V. So, I have replace that with +12 V/1 A SMPS as fulling the -12 V reversing the polarity of SMPS. Then, it worked few weeks well. But now the board power on but stuck. I mean the buttons are not working after pressing power button. When I disconnects the connections of the motor wires from the triacs, buttons are working well. Then I select the wash mode and press the start button. Machine was filling the water. While filling, I reconnected the motor wires, all the functions of the machine was completed as before. No issues was found. Motor was spinning as well.The only way to start the machine is like this. Please someone know a solution for this please let me know.Thanks

author: TheMG
author_rank: Frequent Contributor
timestamp: May 26, 2020, 10:50:34 pm
content: Does the machine have touch-sensitive buttons by any chance (as opposed to traditional clicky mechanical buttons)?

author: Dhanushka
author_rank: Regular Contributor
timestamp: May 27, 2020, 04:33:03 am
content: Old type clicky ones.
What is 4 93A33 ST 9038 (SO8) and 83TI BGG (10pins) SMD please? - Page 1
Forum section: electronics / repair

author: RoGeorge
author_rank: Super Contributor
timestamp: March 04, 2024, 02:35:13 pm
content: The ST one is SO8/SOIC-8, the small one has 10pins. Found them in a ziplock bag. The 3rd one is banana for scale, a 0.1inch DIL. The SO8 one has pins 2-3 in short and from 1 to pins 2 or 3 seems to be a 0.6V diode.Anybody know what these two ICs are, please?

author: RoGeorge
author_rank: Super Contributor
timestamp: March 04, 2024, 03:20:12 pm
content: The 10 pins small one most probably is ahttps://www.ti.com/lit/ds/symlink/tps62056.pdfCan't find the 8 pins one, but all 4 centers pins 2, 3, 6, 7 are tied together internally, with 1 cathode diode to pin 1-2,3,6,7 and another cathode diode from pin 8 to 2,3,6,7.

author: RoGeorge
author_rank: Super Contributor
timestamp: March 04, 2024, 03:46:01 pm
content: By the shorted together pins in the middle, the ST SO-8 most probably ishttps://www.st.com/resource/en/datasheet/l4931.pdf

author: fzabkar
author_rank: Super Contributor
timestamp: March 04, 2024, 05:46:20 pm
content: https://www.ti.com/packaging/en/docs/partlookup.tsp?partmarking=bgghttp://markingcodes.com/search/c/bgghttps://www.aliexpress.com/item/32217263933.html(photo of L4931ABD50)https://ickala.com/linear-regulators/7159-l4931abd33.html(photo of L4931ABD33)https://cdn.ickala.com/8253-large_default/l4931abd33.webp
What is an "NMC 4-11" or "NMC 6-6"? They look like electrolytic capacitors... - Page 1
Forum section: electronics / repair

author: MaximRecoil
author_rank: Regular Contributor
timestamp: August 18, 2019, 09:14:01 pm
content: I plan to replace all of the electrolytic capacitors in an Onkyo T-4055 AM/FM stereo tuner, and I've written down all the capacitors I need, except there are three that look like capacitors, but they don't have voltage rating and capacitance values printed on them. Two of them say "NMC 4-11" and the third one says "NMC 6-6", which corresponds to what's printed on the PCB at the locations where they are mounted. Here's a picture of them:Here's the schematics:They are on the "NAMX-189" PCB, which I've highlighted. I've also highlighted where it says "NMC 4-11" and "NMC 6-6."

author: ataradov
author_rank: Super Contributor
timestamp: August 18, 2019, 09:46:19 pm
content: According to the schematic they are inductors. No need to replace them, they don't age.

author: MaximRecoil
author_rank: Regular Contributor
timestamp: August 18, 2019, 09:54:35 pm
content: Yeah, I noticed the coil symbols next to them, but I've never seen coils that look like aluminum electrolytic capacitors, have you? And if they're coils, what do the "4-11" and "6-6" designations stand for?

author: ataradov
author_rank: Super Contributor
timestamp: August 18, 2019, 10:00:31 pm
content: They look like just part numbers. There are other transformers marked NMC on the schematic. I would assume they come from the same source.Having inductors in metal cans is not uncommon, although I have never seen this specific design.

author: MaximRecoil
author_rank: Regular Contributor
timestamp: August 18, 2019, 10:07:57 pm
content: Okay, thanks.
What is F2V76 complete part number? - Page 1
Forum section: electronics / repair

author: Farah
author_rank: Contributor
timestamp: August 30, 2023, 11:38:53 am
content: I have a Diode on my board with the code "F2V76" on the component. It is a diode but I couldn't fid the full part number and datasheet.

author: fzabkar
author_rank: Super Contributor
timestamp: August 30, 2023, 04:32:12 pm
content: What is the package? Could it be a 2.7V Zener, eg BZX79-F2V7

author: Farah
author_rank: Contributor
timestamp: September 02, 2023, 05:19:08 am
content: Thanks a lot. Yes you are right. It's a Zener diode.
What is the clear compound that protects the pcb - Page 1
Forum section: electronics / repair

author: Aurgelme
author_rank: Contributor
timestamp: October 15, 2023, 10:14:37 am
content: After a repair, I want to protect the pcb in the same way as the manufacturer has done, but have not found out what this flexible substance is called.Appreciate if someone can help me with this

author: Whales
author_rank: Super Contributor
timestamp: October 15, 2023, 10:30:50 am
content: Potting.There are various different chemicals used for potting, including silicones, polyesters and epoxies. I don't know if you have to worry about compatibility.

author: artag
author_rank: Super Contributor
timestamp: October 15, 2023, 12:07:43 pm
content: Potting is the name I'd use for completely encapsulating a circuit in a block, often by filling a plastic pot with one of the compounds Whales mentions.The PCB is very nearly always coated in a thin layer of 'solder resist' which is what stops the solder flooding over every copper surface. You may be wanting to replace this if you've repaired a badly damaged pcb.However if the layer you're talking about is thick and (usually) clear, coating all the components and preventing corrosion or moisture but not hiding the parts, I think the substance you're looking for is 'conformal coating'. Can be rubbery so it may be very similar to potting compound but perhaps different in consistency.

author: Aurgelme
author_rank: Contributor
timestamp: October 15, 2023, 12:26:50 pm
content: Thank you bothI think I found what I was looking for and it was calledH599 Silicone pcb potting heat conduction
What is the easiest way to remove conformal coating from a PCB? - Page 1
Forum section: electronics / repair

author: 4cx10000
author_rank: Regular Contributor
timestamp: May 26, 2020, 07:17:25 pm
content: Hi!A pcb with conformal coating, from a Husqvarna robot lawn mover, is now on my workbench. I have cleaned - well ... tried the best I could - coated boards before, but with poor to medium results. Wonder how you guys solve this and what would be the easiest way to go?

author: chriva
author_rank: Regular Contributor
timestamp: May 26, 2020, 07:23:02 pm
content: It depends on which type of coating but if it's acrylic or epoxy, Acetone usually does a decent job.Method of removal is anything from a soaked toothbrush to just dunking the whole thing in a large container filled with acetone

author: 4cx10000
author_rank: Regular Contributor
timestamp: May 26, 2020, 07:37:33 pm
content: Thanks chriva!How would you describe the difference between acrylic and epoxy coated boards in softness? Guess that those with epoxy coating has harder surface compared to acrylic. My board is, I believe, coated with the latter because it can be peeled off quiet easily, but of course it leave residues and more cleaning is needed.

author: BreakingOhmsLaw
author_rank: Frequent Contributor
timestamp: May 26, 2020, 08:03:16 pm
content: Beware, acetone kills plastics fast. Test before going full speedOn a related note: google for "plunger can". These are great.

author: m3vuv
author_rank: Super Contributor
timestamp: May 26, 2020, 09:09:24 pm
content: i would try some paint stripper.
What is the name of this RF connector type? - Page 1
Forum section: electronics / repair

author: 8008
author_rank: Contributor
timestamp: October 09, 2025, 12:13:11 pm
content: Hello,for a frequency counter, I need two internal replacement cables, with some special connectors at their ends.I have checked the Internet and could not even find out how these connectors are calledFrom another device, that I tore down years ago, I found some sockets of that exact type in my parts boxes. There is the text "EFJ131" written on them. But even with that text, leading to some ebay offerings, I could not find out the exact name of the connector. The connector looks like a very small cinch connector.For the frequency counter, the frequency in these cables are going up to 1GHz.Does anyone know how these things are named?Dennis

author: Uunoctium
author_rank: Frequent Contributor
timestamp: October 09, 2025, 12:22:11 pm
content: that should be SMChttps://www.amphenolrf.com/152145.html

author: 8008
author_rank: Contributor
timestamp: October 09, 2025, 12:57:27 pm
content: Thanks for checking!I am not sure, but it looks like the SMC connector has a thread to fit male+female connector together. "My" connector is without thread, just plugged.And if I understand the datasheet correctly, the diameter of SMC is too large (3.9mm).So close, but not the same?

author: 8008
author_rank: Contributor
timestamp: October 09, 2025, 01:00:51 pm
content: A better image now, where the actual cable with the connector can be seen. No thread there, only plugged connectors.

author: inse
author_rank: Super Contributor
timestamp: October 09, 2025, 01:22:27 pm
content: I‘d say this are SMB connectors

author: Kwakerman
author_rank: Regular Contributor
timestamp: October 09, 2025, 01:46:25 pm
content: SMB (as SMA and SMC are threaded connectors).

author: 8008
author_rank: Contributor
timestamp: October 09, 2025, 02:07:59 pm
content: According tohttps://fieldcomponents.com/smb-connectors.html, SMB has the same/very close sizes, compared to my measurements.So I think yes, these are SMB connectors.Thank you all for checking!Dennis

author: Hamelec
author_rank: Regular Contributor
timestamp: October 09, 2025, 05:07:54 pm
content: its a EIP54x counter? should be SMB..
What is the value of this resistor? - Page 1
Forum section: electronics / repair

author: saaluc
author_rank: Contributor
timestamp: March 30, 2025, 01:57:18 pm
content: Hi thereAs I see the resistor in the attached picture, its bands from right to left are: black, grey, silver, golden. But this would be a 0.08 ohm resistor which does not seem standard. If the third band is golden, it would be a 0.8 ohm resistor which does not seem standard either.What is your idea about the colour of the bands of this resistor especially the third band from right, and the value of the resistor?

author: tooki
author_rank: Super Contributor
timestamp: March 30, 2025, 03:22:52 pm
content: I’ve never heard of 0 (black) being a “legal” first band.So either the black band started life as some other color and darkened with age and heat, or it’s a very odd color code.If it were actually a blue band, then it’d be a very standard 0.68 ohms.

author: saaluc
author_rank: Contributor
timestamp: March 30, 2025, 05:50:05 pm
content: Quote from: tooki on March 30, 2025, 03:22:52 pmThe ohm-meter shows 6.5 ohms for this resistor. It may have been blue, grey, golden, golden: 6.8 ohms.
What is this AHRS chip? - Page 1
Forum section: electronics / repair

author: peter-h
author_rank: Super Contributor
timestamp: October 31, 2020, 07:30:12 am
content: http://peter-ftp.co.uk/screenshots/20201031049963107.jpgObviously Analog Devices but the P/N doesn't google to anything. It is thought to be 12+ years old.(the insert image code doesn't work, btw - wonder if the server for the image must now be HTTPS?)

author: m k
author_rank: Super Contributor
timestamp: October 31, 2020, 10:57:38 am
content: ADXRS613?

author: peter-h
author_rank: Super Contributor
timestamp: October 31, 2020, 12:30:24 pm
content: Yes; must be. Thanks
What is this component - Page 1
Forum section: electronics / repair

author: kamalshah
author_rank: Newbie
timestamp: July 24, 2021, 05:49:57 pm
content: I had bought a this Car cooling fan and it worked fine but later one of the fans stopped working. I took it apart and checked everything I could. and it all seamed to work fine.https://www.aliexpress.com/item/4001118023418.html?spm=a2g0s.9042311.0.0.6f6f4c4ddcUwDpbut the fan would still not work even though the other fan works fine plugged in to this fans wire. So I thought the component in the picture might be the problem. I googled the part number but found nothing. It has 4 prongs and looks like a transistor. it has the following written on it: "0CS 29830 0QAG"

author: Manul
author_rank: Super Contributor
timestamp: July 24, 2021, 05:56:12 pm
content: It is likely OCH29830. It is a hall sensor with some integrated motor driver.

author: fzabkar
author_rank: Super Contributor
timestamp: July 24, 2021, 06:05:02 pm
content: I suspect that it is a Hall Effect sensor.OCS = Shanghai Orient-Chip Technology Co.,LTDhttp://www.orient-chip.com/Pages/ProductList.aspx?cl=en&ClassId=25&SecondId=69&Type=1&Parameter=&ReId=&ReNew=&key=http://www.orient-chip.com/Pages/ProductDetail.aspx?cl=en&id=1823(OCH29830)http://www.orient-chip.com/Upload/File/2020-02-18/202002181350493678.pdf(OCH29830)http://www.orient-chip.com/Upload/File/2020-02-18/202002181354395734.pdf(OCH29831)

author: kamalshah
author_rank: Newbie
timestamp: July 24, 2021, 06:50:08 pm
content: Thanks I could never have guessed it.when I turn it on the motor drives for a couple of revolutions and then stops working.I have a multimeter, Can I test it with that?plus how can I order one to repair it.Thanks again

author: kamalshah
author_rank: Newbie
timestamp: July 24, 2021, 07:25:49 pm
content: This is the circuit behind the coil,

author: kamalshah
author_rank: Newbie
timestamp: July 24, 2021, 07:26:39 pm
content: The fan coil
what is this component - Page 1
Forum section: electronics / repair

author: aakhans@gmail.com
author_rank: Newbie
timestamp: March 22, 2022, 12:21:54 am
content: My coffee grinder stop working, i openend it up and struggling to find what is this part in the picture, if some body can helppart attached to brown wire with metal casing. there is no numbers on it

author: bob91343
author_rank: Super Contributor
timestamp: March 22, 2022, 12:24:14 am
content: Probably an overtemperature switch.

author: aakhans@gmail.com
author_rank: Newbie
timestamp: March 22, 2022, 12:39:53 am
content: you mean thermal fuse ? does it have this shape - its in metal casing sort of ?

author: fzabkar
author_rank: Super Contributor
timestamp: March 22, 2022, 02:38:30 am
content: Some examples here:https://www.mantech.co.za/Datasheets/Products/H20,H21-SERIES_HENG-HAO.pdfhttps://thermostat-china.en.made-in-china.com/productimage/mNDEdtyxhUWs-2f1j00nkTgZtqlOzuI/China-Auto-Reset-Thermal-Switch-Thermal-Fuse-250V-2A-to-20A-Ksd9700.html

author: aakhans@gmail.com
author_rank: Newbie
timestamp: March 22, 2022, 05:22:14 am
content: thanks
What is this connector? - Page 1
Forum section: electronics / repair

author: james_s
author_rank: Super Contributor
timestamp: June 14, 2020, 03:46:55 am
content: This circular connector is used on a veterinary patient monitor, somebody managed to force it in the wrong way and twisted it, shearing off all the pins. A replacement cable is >$100 so I'm wondering if this is a standard connector I can get somewhere to replace it?

author: Audiorepair
author_rank: Frequent Contributor
timestamp: June 14, 2020, 09:38:16 am
content: Could be a "Lemo" connector?https://uk.farnell.com/lemo/fgg-1b-305-clad62z/plug-1b-free-5way/dp/4315212Or you could go through this list of 5-pin cable connectors from Farnell, each will have a datasheet available to click on.https://uk.farnell.com/c/connectors/circular-connectors-components/prl/results?circular-connector-shell-style=cable-mount-plug&no-of-contacts=5contacts

author: mikerj
author_rank: Super Contributor
timestamp: June 14, 2020, 10:04:03 am
content: Quote from: Audiorepair on June 14, 2020, 09:38:16 amLooks like one of theRedel Pseries connectors. Thedatasheetincludes all the dimension needed to identify the variant.

author: james_s
author_rank: Super Contributor
timestamp: June 14, 2020, 06:00:54 pm
content: I think we might have a winner here. I'm gonna have to study the datasheet and take some measurements to confirm and then figure out exactly what variant is needed.

author: Audiorepair
author_rank: Frequent Contributor
timestamp: June 14, 2020, 06:11:57 pm
content: Good result!In my experience, it sometimes turns out that the exact part you need isn't easily available, or has been customised for the manufacturer of this specific product.You may therefore also want to consider whether it is feasible to replace both plug and socket with something else off the shelf that will fit.

author: james_s
author_rank: Super Contributor
timestamp: June 14, 2020, 06:17:29 pm
content: I can't replace the socket, it's an expensive medical instrument that has to work with off the shelf cables and accessories. I'm hoping I can repair the damaged cable, otherwise the option will be just buy the expensive cables.

author: james_s
author_rank: Super Contributor
timestamp: June 29, 2020, 01:22:31 am
content: Just a followup, a Lemo PAG.M0.5GL.AC52G plug fits perfectly, I picked one up from Digikey and installed it on the cable, plugs right in and works fine. In the meantime they ordered a new way overpriced cable so this one will be a backup for the next time someone jams it in wrong.
What is this connector? - Page 1
Forum section: electronics / repair

author: james_s
author_rank: Super Contributor
timestamp: October 18, 2021, 06:02:06 am
content: One of the terminals broke in this connector, I temporarily stuffed a Molex KK pin in there and it works but it isn't quite right. There are a whole bunch of very similar .156" connectors out there, does anyone recognize this specific one?

author: tooki
author_rank: Super Contributor
timestamp: October 18, 2021, 12:44:20 pm
content: At first glance I’d say JST VH series.

author: DavideAndrea
author_rank: Contributor
timestamp: October 21, 2021, 02:17:01 pm
content: It can be any of these:* MANUF. - SERIES* JST - VH* Molex - 35313 + 35156* Molex - L1NK 396* TE - Economy Power 3.96* TE - Economy Power IIAccording to my Connector Identification Utilityhttp://connectorbook.com/identification.html?st=1&nm=by_names&bm=by_compon&c=interior_rect_conn&u=wire_to_board_conn&fl=00100000200000000000301000100000-55c-|3.96|5|||

author: DaJMasta
author_rank: Super Contributor
timestamp: October 21, 2021, 05:04:42 pm
content: Any letters stamped in the housing? Usually there's some sort of maker's mark and when you can narrow it down that way, they probably only have one or two products that match the look.

author: james_s
author_rank: Super Contributor
timestamp: October 21, 2021, 06:48:27 pm
content: I'll take a look next time I'm there, it's at my brother's place. I looked up JST VH pins and they look about right going from memory so I added some to my digikey cart. I'll look up the others and see how they compare.

author: tooki
author_rank: Super Contributor
timestamp: October 21, 2021, 09:38:18 pm
content: Quote from: DavideAndrea on October 21, 2021, 02:17:01 pmVH: itisthis, or a clone thereof.Molex 35313 + 35156: Nope, doesn’t match. Different latch and keying.Molex L1NK 396: Nope, doesn’t match,completelydifferent latch design.TE Economy Power and Economy Power II: while very likely mating-compatible, not a match. The latch has little barriers next to it that the JST VH doesn’t have.As for the database,here’s the link made clickable.(The forum software screws up with many special characters, like the pipe, if you don’t manually create the link and link text.)That’s a neat site! I actually had recently had the thought (as a connector nerd) that making such a site might be useful. Cool to see you’ve undertaken that! I will give a bit of constructive feedback, though: the usability is terrible and it seems rather buggy. (For instance, there’s no obvious way to go back to the list of candidates, once you’ve selected one. The little back arrow next to the number in a circle goes back, but the component list then doesn’t contain all the same items. Browser back doesn’t work, either.)

author: james_s
author_rank: Super Contributor
timestamp: October 21, 2021, 11:44:34 pm
content: That is neat. There are a zillion different connectors out there, many of them very similar and most are not stamped with any sort of part number. I have been frustrated many times trying to find a match for a connector of one sort or another, many times I don't even know what to search for.
What is this device: Analog Devices HS 8 (or B?): 8 pin sot IC - Page 1
Forum section: electronics / repair

author: Sorama
author_rank: Frequent Contributor
timestamp: September 19, 2025, 05:22:37 pm
content: guys,does anyone has an idea what this 8 pin component could be?I can't find it on the net: markings says HS and below that an 8 (or a B), from AD.I can't measure the the pins as it is sandwiched between 2 pcb's.Tnx.

author: amyk
author_rank: Super Contributor
timestamp: September 20, 2025, 03:15:43 am
content: Pictures please...

author: Sorama
author_rank: Frequent Contributor
timestamp: September 20, 2025, 07:00:29 am
content: as said, it's a stacked pcb with only 1 cm space between them, not allowing me to do measurements to reverse engineer the device (a echo scanner for pregnant animals).Some pictures:the device is the 8 pin SOT in front of the connector with markings HS 8.

author: fzabkar
author_rank: Super Contributor
timestamp: September 20, 2025, 08:28:54 am
content: ADA4851-2YRMZ, Analog Devices, dual High Speed, Rail-to-Rail Output Op Amp, marking HSB, MSOP-8:https://www.analog.com/media/en/technical-documentation/data-sheets/ada4851-1_4851-2_4851-4.pdfhttps://gw.alicdn.com/imgextra/i1/411731257/O1CN01LB3FuD1L9kh1VoJwU_!!411731257.jpg(photo)

author: Sorama
author_rank: Frequent Contributor
timestamp: September 20, 2025, 08:41:04 am
content: Quote from: fzabkar on September 20, 2025, 08:28:54 amall right!tnx a lot.I stumbled upon the possibility of an opamp, but it had a completely other naming.
What is this diode ? (Please help me) - Page 1
Forum section: electronics / repair

author: thitou
author_rank: Contributor
timestamp: December 14, 2024, 07:42:42 pm
content: Hello everyone, I'm repairing an acer x330 led projector.The red led no longer lights up, due to a defective diode. If you look at the picture attached, it's the one with 3115 marked on it.Is there a technique to read the codes of the diodes?I tried to find a replacement, but by typing this reference on the internet I get this:https://eu.mouser.com/ProductDetail/Nexperia/PESD5Z3.3115?qs=LOCUfHb8d9vJaxAfWbkFOQ%3D%3DDoes this seem correct to you?The red led seems to work with 5 volts (max), if this can help.Thank you a lot

author: fzabkar
author_rank: Super Contributor
timestamp: December 14, 2024, 09:41:53 pm
content: It looks like the freewheeling diode in a stepdown DC-DC converter. Therefore, your proposed replacement is unsuitable. Instead, it would be a fast Schottky rectifier diode.Can you identify the stepdown DC-DC converter IC? The application diagram might provide confirmation.Otherwise, look here:http://markingcodes.com/search/c/31The "15" on the second line could be a date or batch code.Here is a possible candidate:https://nz.rs-online.com/web/p/schottky-diodes-rectifiers/2636897https://docs.rs-online.com/4293/0900766b8101fb39.pdf(datasheet for RB051L-40)

author: thitou
author_rank: Contributor
timestamp: December 14, 2024, 10:12:34 pm
content: Indeed, I suspected that the diode I had found was not the right one. But I didn't know how to read this code "31 15" with your indications it's a little clearer, thank you very much!Thanks for your research, I'll see tomorrow for the DC DC converter. I'll send you a message right away.Your link for the marking codes database very helpful!!

author: thitou
author_rank: Contributor
timestamp: December 15, 2024, 12:06:15 pm
content: Hello,Here is a picture of the ic. Unfortunately I couldn't find the datasheet.The reference is 1D (or 10) 3749 N5754Thanks!

author: fzabkar
author_rank: Super Contributor
timestamp: December 15, 2024, 05:36:54 pm
content: LT3743https://www.analog.com/media/en/technical-documentation/data-sheets/3743fe.pdfQuote

author: thitou
author_rank: Contributor
timestamp: December 16, 2024, 11:19:58 am
content: Thank you for the datasheet !
What is this IC? - Page 1
Forum section: electronics / repair

author: james_s
author_rank: Super Contributor
timestamp: August 22, 2021, 11:37:06 pm
content: My google-fu is failing me today. I'm trying to find a datasheet for this IC, I believe it's a mosfet half bridge, looks like it's made by International Rectifier and looks like P542G, I expected this to be easy but I've come up dry. Anyone got a link?

author: oPossum
author_rank: Super Contributor
timestamp: August 22, 2021, 11:41:48 pm
content: https://www.infineon.com/dgdl/irf9389pbf.pdf?fileId=5546d462533600a40153561178901daf

author: james_s
author_rank: Super Contributor
timestamp: August 22, 2021, 11:47:26 pm
content: Thanks, I must be tired, for some reason I assumed that number was a date code and a quick search of it didn't net much either, dunno. Anyway that looks like the right part and matches what I've worked out from the circuit.
what is this ic - Page 1
Forum section: electronics / repair

author: esinior
author_rank: Contributor
timestamp: August 26, 2021, 06:30:53 pm
content: hi, i have a 220v motor driver and i think it is a dimmer from its bt138 triac (it goes to a 220-24 trans and then to the motor) and its ic surface is erased and expunged and i don't know its number, does anyone know what this could be?;

author: jpanhalt
author_rank: Super Contributor
timestamp: August 26, 2021, 06:59:31 pm
content: That looks like it may be a Chip on board (COB) :https://en.wikipedia.org/wiki/Chip_on_boardIdentification marks were not erased. They were never there.Your guess is as good as ours.Edit: Oops

author: fzabkar
author_rank: Super Contributor
timestamp: August 27, 2021, 01:11:15 am
content: Quote from: jpanhalt on August 26, 2021, 06:59:31 pmAre you mistaking the knob on the pot for an IC blob?

author: BrokenYugo
author_rank: Super Contributor
timestamp: August 27, 2021, 01:18:31 am
content: Pretty sure the question is about the DIP 16 package with the markings sanded off.

author: DrG
author_rank: Super Contributor
timestamp: August 27, 2021, 02:01:52 am
content: Quote from: BrokenYugo on August 27, 2021, 01:18:31 amAgreed. I don't know what it is. The only think I could suggest is that the OP draws out the circuit as everything else is identifiable. Given that you have a decent idea of what it does, someone could certainly speculate what IC would make sense there. Not terribly helpful, I know.

author: esinior
author_rank: Contributor
timestamp: August 27, 2021, 05:18:06 pm
content: no,it is cleared and sanded

author: esinior
author_rank: Contributor
timestamp: August 27, 2021, 05:22:22 pm
content: oooooi didn't notice it, i didn't say that , ic is that 16-pin DIP one

author: esinior
author_rank: Contributor
timestamp: August 27, 2021, 05:23:49 pm
content: yes, the question is about that

author: esinior
author_rank: Contributor
timestamp: August 27, 2021, 05:28:29 pm
content: Quote from: DrG on August 27, 2021, 02:01:52 amit is a dimmer i think, doesn't anyone have an dimmer design with an ic?

author: amyk
author_rank: Super Contributor
timestamp: August 27, 2021, 07:32:01 pm
content: U2010B ? Seems to match the circuit at first glance.

author: esinior
author_rank: Contributor
timestamp: April 23, 2022, 08:31:48 am
content: thanks, i'll check that

author: inse
author_rank: Super Contributor
timestamp: April 23, 2022, 02:48:49 pm
content: If it was a dimmer - wow!Not a single piece of filtering or protection around the TRIAC.
What is this part? - Page 1
Forum section: electronics / repair

author: wictor
author_rank: Regular Contributor
timestamp: February 15, 2023, 06:50:39 am
content: I'm repairing 200A TIG welder and there is a component that I haven't seen before. It's like a transformer and it has a black cap with two wires coming to it. Is it some kind of relay or what? I'll try to attach image...

author: ataradov
author_rank: Super Contributor
timestamp: February 15, 2023, 07:54:51 am
content: It is some specialized transformer for welders. If you search what is written on it, you will find some Thai site that sells them. Translating the listing name shows that it is a gate driving transformer.Some of the listings even include the whole module board withe capacitors and diodes.If it is dead, then it looks like there is no chance of finding a replacement.

author: mon2
author_rank: Frequent Contributor
timestamp: February 15, 2023, 09:40:15 am
content: https://shopee.co.th/Hang-sing-%E0%B8%AB%E0%B8%A1%E0%B9%89%E0%B8%AD%E0%B9%81%E0%B8%9B%E0%B8%A5%E0%B8%87-16-8-%E0%B8%AB%E0%B8%A1%E0%B9%89%E0%B8%AD%E0%B9%81%E0%B8%9B%E0%B8%A5%E0%B8%87%E0%B9%80%E0%B8%81%E0%B8%95%E0%B9%84%E0%B8%94%E0%B8%A3%E0%B9%8C-%E0%B8%AD%E0%B8%B0%E0%B9%84%E0%B8%AB%E0%B8%A5%E0%B9%88%E0%B8%95%E0%B8%B9%E0%B9%89%E0%B9%80%E0%B8%8A%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%A1-..-i.105451361.4378682352

author: coromonadalix
author_rank: Super Contributor
timestamp: February 15, 2023, 03:53:24 pm
content: it saysHang sing Transformer 16:8 Gatedrive Transformer Welding

author: wictor
author_rank: Regular Contributor
timestamp: February 15, 2023, 08:14:16 pm
content: Thanks to all!
what is this part? - Page 1
Forum section: electronics / repair

author: vixo
author_rank: Regular Contributor
timestamp: October 05, 2023, 02:38:33 pm
content: I think this part says BD4 5C14 but I can't find in any database a reference for this part code, does anyone know? Help much appreciated!

author: Zenith
author_rank: Frequent Contributor
timestamp: October 05, 2023, 03:15:22 pm
content: Which equipment is a part of? That may help shed some light on it. Can you get the manual for the equipment?Looking at the picture it appears to be designated D4, which suggests it's a package of diodes.

author: Daixiwen
author_rank: Frequent Contributor
timestamp: October 17, 2023, 06:53:13 am
content: Doesn't D4 apply to the diode in the bottom left hand corner? The reference designators on that silkscreen are a bit all over the place

author: Psi
author_rank: Super Contributor
timestamp: October 17, 2023, 07:26:45 am
content: Logo might be Torex Semiconductors

author: mengfei
author_rank: Regular Contributor
timestamp: October 17, 2023, 07:53:05 am
content: might helpgood ol Picasa 3 functions

author: Psi
author_rank: Super Contributor
timestamp: October 17, 2023, 07:55:56 am
content: Definitely looks like Torex Semiconductors, you can now see the curve of the linePretty sure the package style is called MSOP-10 by Torex

author: mengfei
author_rank: Regular Contributor
timestamp: October 17, 2023, 08:00:38 am
content: Quote from: Psi on October 17, 2023, 07:55:56 amwhich country is Torex originally from?Heard before but never came across some of our projects

author: Psi
author_rank: Super Contributor
timestamp: October 17, 2023, 08:12:16 am
content: If you go here and then click "Products using this package" you find some things that could be ithttps://product.torexsemi.com/en/packages/msop-10Ground is on pin9, which is correct. But i cant match up any of the part numbers to the part numbers on the chip.Its possible its an older obsolete/previous version of these IC'sCheck what pins that inductor to the right is across, and match them up to the datasheets.

author: janoc
author_rank: Super Contributor
timestamp: October 17, 2023, 12:19:11 pm
content: That pin 4 soldering looks a bit dodgy. If that IC is causing problems touch the soldering up.

author: wasedadoc
author_rank: Super Contributor
timestamp: October 17, 2023, 05:08:07 pm
content: Looks more like 3B4 to me.

author: fzabkar
author_rank: Super Contributor
timestamp: October 17, 2023, 06:52:30 pm
content: I'm not sure about this one ...https://product.torexsemi.com/system/files/series/xc9502.pdfIt's a different IC, but the marking codes for the XC9128/XC9129 might provide clues. For example, it appears that the feedback voltage is 0.45V.https://product.torexsemi.com/files/status/xc9128.pdfEdit: Could "3B4" be "8B4", in which case the IC could be XC9128B45CAR?http://markingcodes.com/search/c/8b48B4+5CXX --> XC9128B45CAR
What is this part number of this Photovoltaic Power Converter  - Page 1
Forum section: electronics / repair

author: teatime
author_rank: Contributor
timestamp: March 07, 2024, 09:12:16 am
content: Apply the red laser(about 840nm)via E2000 connector to this Photovoltaic Power Converter,normally will output 6V dc without loading.I cannot see any character on this component.The similar model is 6 V Photovoltaic Power Converter (PPC-6E) made by Lumentum Operations LLC.Would you please advise the right model of this component.Thank you very much!

author: Jwillis
author_rank: Super Contributor
timestamp: March 08, 2024, 07:55:35 am
content: Sorry but This was all I could find was this PDF. I don't really know much about fibre optics aside from concept.Hope it helps some.

author: teatime
author_rank: Contributor
timestamp: March 12, 2024, 02:07:05 am
content: I hope the expert will help me find the exact part numebr of this part.Thanks.
What is this resistor? - Page 1
Forum section: electronics / repair

author: wadmancpu
author_rank: Contributor
timestamp: November 13, 2019, 07:46:15 pm
content: Am I crazy or isn't this a 2,000 ohm resistor? Also isn't this ceramic? I can't seem to find these either. Thanks all.

author: schmitt trigger
author_rank: Super Contributor
timestamp: November 13, 2019, 08:11:49 pm
content: This looks very similar to fusible resistors found as in-rush limiters in high power supplies.Low power supplies can use a thermistor as an inrush limiter, but even at its lowered resistance can create high losses.Therefore a high power supply usually employs a fixed resistor that is fully shorted out by a relay after a set time.However...if for whatever reason the relay contact's do not close, the resistor will become cherry-hot and could actually cause a fire.Thus, these types of resistors have a thermal cutout which will permanently open if the resistor's maximum temperature is exceeded.Having said this, for a more accurate answer, would you kindly tell us the circuit you remove this resistor from?

author: Yansi
author_rank: Super Contributor
timestamp: November 13, 2019, 08:19:42 pm
content: wirewound R2 = 0.2ohm, K=10% tolerance.Salvaged from an audio amp, guessing.

author: Yansi
author_rank: Super Contributor
timestamp: November 13, 2019, 08:25:33 pm
content: Quote from: schmitt trigger on November 13, 2019, 08:11:49 pmResistors with thermal cutout look different.¨Thermal cutout would be explicitly stated on it. I think this one is a bog standard wirewound 0.2ohm one. Fusible resistors are also very different kind.This is how resistor with thermal cutout looks like:

author: wadmancpu
author_rank: Contributor
timestamp: November 13, 2019, 08:30:04 pm
content: This out of a tv power supply. Thank you for the specs on this. It was testing shorted and I thought 2k would be 2,000 ohms. I see now .2 ohms why it tests the way it does. Does anyone have a link that shows what these numbers and letters indicate?

author: Yansi
author_rank: Super Contributor
timestamp: November 13, 2019, 08:32:37 pm
content: R is the standard character for OHM, while K is standard identificator for 10% tolerance.These letters are also used extensively on other passives such as foil capacitors. J, K and M being the most often seen.//EDIT: More on the markings here:http://www.iequalscdvdt.com/Markings_and_Codes.html//EDIT2: On my photo of resistors with thermal cutout, you can see the letter J used to identify +-5% tolerance of those 10 ohms.

author: wadmancpu
author_rank: Contributor
timestamp: November 13, 2019, 10:59:04 pm
content: Excellent, thank you!

author: schmitt trigger
author_rank: Super Contributor
timestamp: November 14, 2019, 04:09:54 am
content: Thanks for the clarification.