hybridfree/eevblog-posts huggingface dataset:
[SOLVED] SMPS fuse keeps blowing - Page 1
Forum section: electronics / repair

author: fullbridge
author_rank: Newbie
timestamp: November 25, 2021, 11:16:10 am
content: The fuse on the Neutral side keeps blowing after 5 seconds. I measured all of the capacitors in parallel with the AC power coming in and they are open circuit. I tired heating up the NTC resistors with a lighter and they do change resistance with temperature. I measured the coils and they are not shorted.See attached photo and schematic.When I first looked at the board I found a transistor attached to a heat sink on the switching side that literally blew up: P11K507FF. I replaced it but the fuse still keeps blowing. It looks like whatever blew up that transistor also destroyed something else on the board.

author: wn1fju
author_rank: Frequent Contributor
timestamp: November 25, 2021, 12:59:35 pm
content: You said: "It looks like whatever blew up that transistor also destroyed something else on the board." It may be the other way around, namely something else wrong with the board blew up that transistor.Check the secondary side for shorts with an ohmmeter. Look for shorted electrolytic caps, shorted flyback diodes, shorted regulator ICs, etc.On the primary side, you might want to pull the switching transistor, then check resistances for things like shorted caps and shorted bridge rectifiers.The web pagehttps://www.repairfaq.org/sam/smpsfaq.htmhas lots of good information.And be careful if you don't know what you are doing. Switching supplies can kill you if you stick your hands into things with it powered up.

author: fullbridge
author_rank: Newbie
timestamp: November 25, 2021, 03:03:34 pm
content: Thanks for the useful suggestions and manual. I found a shorted diode in the PFC section, replaced it and now the fuse is not blowing.I just noticed that I took out some small 8 pin ICs past the opto-coupler to try in another SMPS of the same typeI will put those ICs back and see if I get something on the output. I measured the optos and there's voltage on them so I'm hoping to get something out once I put the chips back in.The semiconductor parts in this thing are hard to find on eBayso I'm swapping components between broken boards.

author: ambrosia heart
author_rank: Regular Contributor
timestamp: November 25, 2021, 03:12:02 pm
content: The fuse on the Neutral side keeps blowing after 5 seconds.I don‘t have time to read your long composition.Do your SMPS have a similar structure as pictures shown?If yes, check those components I sent to you via pm.If no, ATX structure, just throw it away.Don‘t waste time.I am now watching a cartoon called 鬼滅之刃；no time to read long composition.
SMPS over voltage? - Page 1
Forum section: electronics / repair

author: tronick
author_rank: Newbie
timestamp: April 17, 2024, 11:41:03 pm
content: Hello! I am repairing two 120VAC in, 24VDC @25A out power supplies with matching failures. The fans stopped running and a long slow over heat occurred until a capacitor failed in both. I replaced the bad capacitors and checked everything else within reach and they power up OK. They are producing smooth 24VDC. However, once a load is applied drawing any more than about 2.5A, an OVP or over voltage error occurs causing it to shut down and illuminate the OVP led. The output does creep up to around 26 VDC before shutdown. Incidentally, there is an audible hi-freq 'squeal' heard from the unit once a load is applied that continues after load is removed, before tripping the OVP. I have tested everything for obvious failures with a DVM and all other components seem 'OK' so far. I have also replaced the opto-coupler and 15V regulator, no change. What would cause the supply to be unable to be unstable under a load? Thanks for any help! Will try to post a schematic as well.

author: m k
author_rank: Super Contributor
timestamp: April 26, 2024, 03:35:16 pm
content: So feedback is leaving behind.Internal 15V must be enough and remain like that.U102A pin 3 is feedback voltage.U101 pin 7 is feedback current.
smps power supply  - Page 1
Forum section: electronics / repair

author: Turbochardged
author_rank: Contributor
timestamp: May 30, 2024, 07:16:28 pm
content: First thing, I'm self taught so I apologies ahead of time.I'm working on a 12v DC 20A SMPS Universal Regulated Switching Power Supply for cctv, all i've found bad so far is one of the main NPN switching transistors failed. It's a Fairchild J13009 (TO-247). When searching all i find is a FJ13009-2 (TO-220) i Can't find a data sheet on it. All i know is it's a "NPN high-voltage fast-switching power transistor" It's your typical 12v Chinesium supply. Whatever you dig up would be appreciated, either a data sheet or a comparable replacement. I'm sure i forgot to add something.

author: SeanB
author_rank: Super Contributor
timestamp: May 30, 2024, 07:25:23 pm
content: How abouthttps://www.farnell.com/datasheets/1852081.pdfYes TO220, but in a SMPS it will work, just remember to fix the thing that killed it first, likely the primary side start up capacitors, typically a 100 to 220uF 63V capacitor there on the primary side.

author: Turbochardged
author_rank: Contributor
timestamp: May 30, 2024, 08:47:27 pm
content: that one is a 12A and I'm not sure how well the TO-220 will fit in the TO-247 socket and heatsink.
SMPS Repair - Allen and Heath 6 Channel Mixer - Page 1
Forum section: electronics / repair

author: batou
author_rank: Contributor
timestamp: March 09, 2021, 10:15:18 pm
content: Hi, can anyone help me understand whats wrong with this SMPS? U2 is a TNY287. U3 and U4 are 7812 and 7912 regs respectively. U4 had a small hole / burn marks and has been replaced. D7 is an SB1100 schottky that was shorted - also replaced. Other diodes test ok in-circuit. Main filter caps test OK and are sittng at 330v. Output voltages are as follows:P1: 37.1vP8: 3.6vP12: -24vP9: -12vAny tips/pointers of what it could be, or what to test next are greatly appreciated!

author: KevinA
author_rank: Regular Contributor
timestamp: March 09, 2021, 10:33:42 pm
content: No idea what model you have, but this is the manual I did for my techs ten years ago for the ZED series, it may provide a few clues for you.

author: batou
author_rank: Contributor
timestamp: March 09, 2021, 10:37:56 pm
content: I think its actually doing whats its meant to do! The point I was taking as ground isn't ground relative to the regs. D'oh.Thanks for the PDF!
SMPS repair - primary side controller not starting up/driving gate - Page 1
Forum section: electronics / repair

author: MateV
author_rank: Newbie
timestamp: April 19, 2024, 11:42:28 am
content: Hello!I've been trying to repair a blown SMPS, and got stuck.The original fault seems to be Q9101(TK13A65U) going short, burning out R9101 in the process. C9104(OCP filtering) and R9108(gate resistor) were also bad, along with U9102(feedback optocoupler) having very low emitter-collector resistance.Measured and replaced everything that was bad in this area, along with U9101.Powering on the PSU results in the following on the Vcc pin of U9191:There never seems to be any gate drive output, except a few picoseconds ~2V pulse, which I assume is just some sort of noise(no voltage detectable on any output on the transformer either).Removing power from the PSU causes the following oscillation on Vcc until Vbus drops under ~20V:U9101 looks to be this with a custom part number:https://www.semicon.sanken-ele.co.jp/sk_content/ssc1s311a_ds_en.pdfFull schematics:https://elektrotanya.com/715g7831-p0e-000-0020_philips_psu.pdf/download.htmlAny help or suggestions on what to measure would be greatly appreciated!Thanks.

author: Gyro
author_rank: Super Contributor
timestamp: April 19, 2024, 12:02:35 pm
content: Welcome to the forum, MateV.It's a bit of a long shot, but maybe C9103 has dried out, particularly if it's near hot parts. These small switcher VCC reservoir caps are notorious for causing startup problems in SMPSs. It's worth a check anyway.

author: wraper
author_rank: Unknown
timestamp: April 19, 2024, 12:06:04 pm
content: Check ESR/replace C9103, C9128. As optocoupler was bad, I'd expect ZD9107 and probably ZD9101 and C9102 being bad too.

author: MateV
author_rank: Newbie
timestamp: April 19, 2024, 01:02:15 pm
content: Woo, it seems to work! (at least for primary side switching, PSU output is still not quite good)Don't have an ESR meter, so couldn't measure the caps, but their capacity is good. Replaced them anyway, along with all the zeners mentioned.I suspect it was ZD9107, the board is very very slightly discolored under it.Thanks to both of you for the help!
SMPS Seems to have excessive voltage drop and voltage fluctuations Riden RD6018 - Page 1
Forum section: electronics / repair

author: ThermallyFrigid
author_rank: Frequent Contributor
timestamp: June 25, 2021, 02:37:40 pm
content: I just received an NVVV SMPS S-600-60. 600watts and 60vI installed it into a Riden RD6018WThe unloaded voltage fluctuates from about 60.1 to 62.1 with nothing connected. I tested another power supply in this same Riden unit and there is no such fluctuation so it is the NVVV PSUAlso, when I put a 1amp load on the NVVV power supply there is a voltage drop of nearly 8% from 61v to sometimes as much as 53v. it fluctuates.Since none of my other power supplies do this and are basically rock solid at a steady unloaded voltage and have very little voltage drop a light loads, I assume this is a defective power supply.Is this a reasonable assumption?Thanks

author: T3sl4co1l
author_rank: Super Contributor
timestamp: June 25, 2021, 03:35:36 pm
content: Whazzat, the ~$40 PSU from Amazon? I see a few hits like that at least, random brands, price way too low.If it's actually capable of nameplate rating (or functional at all), it's probably not great. Who knows how noisy it is. I'd at the very least want to inspect it in detail, for HV clearance, component ratings, noise output, operating range, etc.How about a nice brand name MeanWell or the like?The RD6018 thing probably isn't all that quiet either... no idea, would have to test. None of these things have any meaningful test data; if they have any regulatory symbols, I expect they're decorative only...Tim

author: ThermallyFrigid
author_rank: Frequent Contributor
timestamp: June 26, 2021, 04:27:40 am
content: Anyone know if those numbers I posted sound right for a good SMPS ?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: June 26, 2021, 05:33:10 am
content: No.I can't be sure if you're doing something wrong, or your load is weird or something, but those don't sound correct and you are right to be suspicious. Hence the conclusion implied by my earlier reply.Tim
SMPS shuts off - Page 1
Forum section: electronics / repair

author: dannemange_
author_rank: Newbie
timestamp: July 11, 2020, 03:52:25 pm
content: I got this Sony DHR-1000 miniDV recorder that didn't power on. Opening it up I saw that R115 was split in two so I replaced that, and measured that Q101, Q102 and Q103 were bad so I replaced those too. Plugging it in gave the correct voltages, until I tried turning the machine on. No more output voltages. I replaced PH101 but that didn't help. I replaced all the capacitors and now when plugging it in, I get the correct voltages for about a second then it disappears. No chance of turning the machine on. What am I missing here? I've tried swapping the power supply with a good one just to make sure the rest of the machine works, and it does, so it's something on this board that's making my head hurt.

author: dannemange_
author_rank: Newbie
timestamp: July 11, 2020, 04:38:41 pm
content: R110 was a little high. Ok to replace with a higher W or will that disrupt the sensing in any way?

author: dannemange_
author_rank: Newbie
timestamp: July 11, 2020, 04:46:16 pm
content: Will do that, thanks for your help!

author: SeanB
author_rank: Super Contributor
timestamp: July 11, 2020, 05:22:46 pm
content: R102. R103 and C102 are also suspicious, measure the resistors and replace if high in velue, and with the capacitor easiest to just replace with a new one, as it likely is low in value and high in ESR. Check the output capacitors as well, especially C202 and C203, as they can cause issues with the feedback.

author: dannemange_
author_rank: Newbie
timestamp: July 11, 2020, 06:13:58 pm
content: Must've mixed up the pdf files here. The above picture shows the US version and this is the EU one I'm trying to fix. Either way I'll go over the resistors and see what they're up to.

author: dannemange_
author_rank: Newbie
timestamp: July 28, 2020, 11:12:15 pm
content: After measuring all of the resistors and not finding anything weird, I decided to still replace them as I've tried everything else. Still no luck... turned out that the new C206 I put in which measuring fine, didn't do its job. Put in a new one and everything works as it should. Don't know if this will help anyone else, but I'm glad I got some guidance here. Thanks guys!

author: tautech
author_rank: Super Contributor
timestamp: July 30, 2020, 07:19:15 am
content: Hmmm, how could that happen.Did you have the cap installed backwards ?

author: dannemange_
author_rank: Newbie
timestamp: August 17, 2020, 08:02:48 pm
content: No sir. Installed it the same way and worked just fine.
SMPS theroy question - Page 1
Forum section: electronics / repair

author: gobo207
author_rank: Contributor
timestamp: April 24, 2020, 08:23:16 am
content: Hi all, electronic theory question ahead,Quick background - I'm repairing a SMPS in an Dick Smith LCD TV. It looks like the MOSFET had failed dramatically so I replaced all the affected components. It still wont switch so I now suspect the PWM controller got a taste of 240v where it shouldn't have.While diagnosing the IC I pulled up the datasheet and found the attached diagram and had a question. With reference to the application circuit in the datasheet, how is it that the VDD voltage is generated since there is no switching on the transformer?The IC is a OB5269, datasheet attached.Regards,GoBo

author: keymaster
author_rank: Regular Contributor
timestamp: April 24, 2020, 08:49:25 am
content: the chip draws a small power from the pin 8 HV to start the operation , then it continuous to operate with power from the transformer.edit: At page 8 of the pdf is the theory of operation .

author: gobo207
author_rank: Contributor
timestamp: April 24, 2020, 09:15:59 am
content: Thank you, that makes sense! Probably should've read all the datasheet....Would something like this be a suitable replacement? It's getting all the inputs it needs and still not switching.https://au.rs-online.com/web/p/pwm-current-mode-controllers/1784578/Datasheet:https://docs.rs-online.com/074d/0900766b8167ad34.pdfRegards,GoBo

author: PKTKS
author_rank: Super Contributor
timestamp: April 24, 2020, 11:10:30 am
content: If you succeed report the steps..I have a similar issue with a similar OBxxx chipset.Ordered a batch of 5 of them...replaced the chip - it works kinda strangefor 15 minutes and went dead by itselfStill thinking if I will shot the next 4 piecesor just brick those crappy chipsets.Paul

author: gobo207
author_rank: Contributor
timestamp: May 14, 2020, 01:52:44 am
content: I ended up replacing it with the ON Semiconductor NCP1239JD65R2G which looked like a good fit given the datasheet. Worked out of the box! Has it running all day yesterday to "burn it in" and no issues. Taped up all the breather ports to get it warmer.GoBo207
SMPS Transformer Replace - Page 1
Forum section: electronics / repair

author: 2X
author_rank: Frequent Contributor
timestamp: September 27, 2023, 06:35:34 pm
content: Hello,I have a PCB where the SMPS transformer is burned. I replaced with another that I have from another same PCB (is from an old same exactly machine) and the circuit works fine. I write the number "34115ADM-T1" on the internet but I didn't find nothing at all. Do you know if can I find another SMPS transformer to replaced it and what specs I have to look? At the attached pictures are the transformer windings and the resistance between them (at excel picture/table).

author: Audiorepair
author_rank: Frequent Contributor
timestamp: September 27, 2023, 06:46:35 pm
content: SMPS transformers are usually custom wound for that particular SMPS.They are not off the shelf parts.So you won't get a replacement.

author: u666sa
author_rank: Frequent Contributor
timestamp: September 27, 2023, 08:49:40 pm
content: Under microscope look at where the windings connect to legs. Copper wires to legs. Usually you will see separation there. That's usually is all that is burned. If you see such condition, fine solder tip and no flux, and Bob is your uncle.

author: 2X
author_rank: Frequent Contributor
timestamp: September 27, 2023, 09:56:08 pm
content: The transformer has blown out.
SMPS with shorted mosfet - Page 1
Forum section: electronics / repair

author: trondl
author_rank: Regular Contributor
timestamp: September 12, 2021, 08:23:47 pm
content: It must be said that I am comfortable with linear psu's, but SMPS repair is new to me.I recently found that my Ensoniq DP/2 audio fx unit was completely dead.It hadn't been used for a while.About 5 years ago I bought this replacement wall wart psu, as I bought it 2nd hand without a psu.The psu was sold specifically for the Ensoniq by a US synth repair site.It provides +/-12v and +5, so a fairly common setup.Probably not important, but it has been feeding on Norwegian 230VAC.First thought was to measure the psu output, and it was completely dead on all rails.I then continued to open the wart and quickly saw that heat had taken place on the pcb.The culprit must have been the K2645 n-ch mosfet, and my humble knowledge tells me that this is the pwm on the primary side.Diode mode and resistance on dmm told me quickly that this had shorted in all directions, also out of circuit (Finally, my first failed transistor!).Before even attempting to order a K2645 or equivalent, I fear something else may have failed here.What should I look for?I cannot see something resembling a fuse anywhere.Since this happened on the primary side, could ugly things have ended up on the output on the secondary?Must the SMPS be loaded to have any output?Thanks for any advice!

author: mariush
author_rank: Super Contributor
timestamp: September 12, 2021, 09:06:35 pm
content: You'd want to look for 2sk2645 or compatible ... add the 2s in front . here's a potential datasheet:https://pdf1.alldatasheet.com/datasheet-pdf/view/60929/FUJI/2SK2645.htmlCheck every diode (the bridge rectifier, the diode after secondary transformer). Check every resistor... especially if there's a resistor directly connected to the mosfet, double check that dark green film capacitor.Ideally you'd check the ESR of secondary capacitors with an esr meter. There's a to-92 component by that capacitors that's probably the voltage reference, make sure it outputs something.
Smps/travel charger with yellow usb connector ? - Page 1
Forum section: electronics / repair

author: abdulbadii
author_rank: Frequent Contributor
timestamp: January 29, 2023, 11:28:30 am
content: Anyone happen to know what is it Smps or travel charger with yellow usb connector supposed to mean ?Imho, has no rectiying D at T ouput so the DMM cant read DCV unless interposed by a D

author: wasedadoc
author_rank: Super Contributor
timestamp: January 29, 2023, 11:36:36 am
content: Given the general dirt, corrosion and condition of the whole unit, the yellow in the USB socket just looks like aged white plastic to me. Possibly caused by sunlight and/or chemicals.

author: Haenk
author_rank: Super Contributor
timestamp: January 29, 2023, 03:44:54 pm
content: Let me google that for youhttps://tech-fairy.com/what-is-the-meaning-of-the-different-usb-port-colors-blue-teal-blue-yellow-red-black/short: no special meaning, just "always on" - which does make sense on a charger (but would be more meaningful on, say, a computer port)
SMT marking AQT B A/D - Page 1
Forum section: electronics / repair

author: Neoxy
author_rank: Newbie
timestamp: March 15, 2023, 01:30:40 pm
content: Hello everyone,After a lot of searching on the net and even ChatGPT I cannot find a component that has the marking AQT. After some reverse engineering I concluded that this is some type of voltage supervisor with a threshold voltage of cca. 1.22V. The package is DFN-8 and input voltage is greater than 24V. When voltage is below 23.5V the IC has its output open-drain active and disables (pulls to ground) a DC/DC buck converter.The correct orientation could not be found as the IC went up in flamesBut I suspect the pins to be: 1 - Vin (24V+), 2 - GND, 3 - GND, 4 - NC, 5 - GND, 6 - Vin(24V+), 7 - OUTPUT, 8 - REFERENCE (24V to voltage divider to 1.22V threshold). I suspect that pins 2,3, 6 could be some settings pins.I would really appreciate some help if someone came across this small component. This component is in the MAN Yacht motors Electronic Lever control. Checked all SMD codebooks, compared Farnell and Mouser IC supervisors to no avail.Thank you and best regards

author: ffranzini
author_rank: Contributor
timestamp: March 15, 2023, 03:56:59 pm
content: Take a look of this TC1301AQTAVMFCombined voltage regulator and voltage detectorRegardsFrancesco

author: Neoxy
author_rank: Newbie
timestamp: March 15, 2023, 06:31:22 pm
content: Thanks for the reply. This one was the first IC I checked. Sadly the pinout is not a match and I am certain it is not the part I am looking for as the absolute maximum Vin is 6V. In my case Vin is 24V.

author: fzabkar
author_rank: Super Contributor
timestamp: March 15, 2023, 06:54:04 pm
content: Maybe a photo of the PCB would help.

author: Neoxy
author_rank: Newbie
timestamp: March 16, 2023, 08:40:33 am
content: I took some photos but I doubt they will be of any help. The board is covered in thick lacquer and it is very hard to work with. I even went so far to decapsulate the faulty component and exposing the die to see if has any markings or at least manufacturer name on the die but was not lucky

author: Neoxy
author_rank: Newbie
timestamp: March 16, 2023, 10:02:52 am
content: Ok guys, I think I wonAfter giving the silicon die one more try I barely distinguished the MAXIM logo. (My stereoscope is sadly not hi end). This led me to the:https://www.stg-maximintegrated.com/en/design/packaging/topmark.htmlThere were multiple hits for AQT. But After going through the datasheets I conclude the part I was loking for is the MAX16010TAB-T. Does anyone wish to confirm my findings?https://www.stg-maximintegrated.com/en/products/power/supervisors-voltage-monitors-sequencers/MAX16010.htmlThank you for all the help. Best regards

author: fzabkar
author_rank: Super Contributor
timestamp: March 16, 2023, 03:49:50 pm
content: Looks good to me. Congratulations.

author: Swake
author_rank: Frequent Contributor
timestamp: March 19, 2023, 11:35:42 am
content: I'm impressed!
SMT trimmer capacitor tuning tool ? - Page 1
Forum section: electronics / repair

author: DimitriP
author_rank: Super Contributor
timestamp: September 15, 2019, 02:02:46 am
content: My current tool is a clipped component lead, slightly flattened using needle nose pliers, that kinda sorta "fits".I tried filing one of my plastic diddle sticks, but by the time you get to the microscopic size there is barely any plastic left to engage.Can anyone recommend a tuning tool for microscopic variable capacitors ?

author: shakalnokturn
author_rank: Super Contributor
timestamp: September 16, 2019, 06:18:49 pm
content: How small are your capacitors? Photo?Anything like the Johanson Thin-Trim series?

author: DimitriP
author_rank: Super Contributor
timestamp: September 16, 2019, 07:42:15 pm
content: Quote from: shakalnokturn on September 16, 2019, 06:18:49 pmI didn't take a picture of the variable capacitor but the variable resistors in the picture are similar in size - They make the 'scope probe look like a telephone pole by comparison :

author: DimitriP
author_rank: Super Contributor
timestamp: September 16, 2019, 08:14:55 pm
content: Here is the actual picture of it on the board and another found online that shows more detail

author: shakalnokturn
author_rank: Super Contributor
timestamp: September 16, 2019, 08:21:42 pm
content: https://www.rf-microwave.com/en/trimmer-adjustment-tools/163/You'll find similar stuff on Amazon, Aliexpress...I'd go for the models with stainless, ceramic or aluminia tips.

author: shakalnokturn
author_rank: Super Contributor
timestamp: September 16, 2019, 09:17:47 pm
content: Your trimmer looks like a Murata TZR1 or TZY2 series for which specific Murata tuning tools have been made, I doubt you'll ever find one though.

author: Mechatrommer
author_rank: Super Contributor
timestamp: September 16, 2019, 09:26:24 pm
content: looks like one among these...https://www.ebay.com.my/itm/10-pc-Triming-Trimmer-Tool-Set-Electronic-Preset-adjustment-alignment-911/362744408778?hash=item5475406aca:g:sRUAAOxy14VRRZK-last time i was search for trimming tool supply similar to the one used by and supplied with dso probe (cross on one end flat on the other end) but either no supplier, or the price is unreasonable from the USA. i have those pictured small smd trimmer resistor as well and TH variable capacitor with cross head...
SMU200A (B) Synthesis Reference PLL unlocked - Page 1
Forum section: electronics / repair

author: drhex
author_rank: Regular Contributor
timestamp: January 19, 2025, 03:55:30 pm
content: Hi all,I have a dual channel 3GHz SMU200A on my desk which shows "(B) Synthesis Reference PLL unlocked". Scoping A and B together they seem to be perfectly stable, I can move the phase in the reference dialog. Ref is on the loop between the SSYNs, removing the loop decouples A and B. Ref is also present on the back connector. Injecting an external reference doesn't make a difference. Service manual suggests changing A2240, I tried two other ones, same error. Internal adjustments pass fine.All of this makes me think that I either don’t understand what is going on or I have an issue with the reference lock state being communicated correctly to the software.R&S is its usual stony self, no help from them as no company. I posted in the groups.io R&S group as well.Thanks,Florian

author: drhex
author_rank: Regular Contributor
timestamp: January 19, 2025, 06:07:07 pm
content: So decided to completely uninstall the software with the uninstaller and the cleaning script. I then put on SP3 for good measure (yes, not officially supported but I don't have the original install media) and reinstalled the R&S software (latest, 3.20.286.21). That fixed it, at least for the moment.Now for installing the 6GHz option, does anybody have a set of cables perchance?

author: drhex
author_rank: Regular Contributor
timestamp: January 19, 2025, 11:20:02 pm
content: This didn‘t last long, level adjustment brought the error back. Any ideas welcome.

author: DaJMasta
author_rank: Super Contributor
timestamp: January 20, 2025, 01:02:25 am
content: Can you see any glitches in the back connector output when the error shows? It could help determine if it's a problem with the reference oscillator and its loop or if it's the way a synthesizer is locking to it. Since any external input is still going to be locked into the reference PLL, you can get similar behavior even when using the internal one if it's the loop that has the issue.
SN75518FN replacement - Page 1
Forum section: electronics / repair

author: RichardDiag
author_rank: Newbie
timestamp: August 14, 2023, 10:28:28 pm
content: Had someone ask me about an issue with a VFD (vacuum fluorescent display) on an HP/Agilent 33120 function generator. The issue being a dot in the ';' always being on. This suggested the driver chip, a SN75518FN was likely the issue. It also seems that several HP/Agilent equipment uses this part. Finding a replacement SN75518 was not looking good. After a few hours of searching, I did finally find two parts that appear to be possible replacement parts. I thought I would relay that info for someone else whom my be looking.It appears that Microchip HV518 and Analog Devices MAX6934 are compatible parts for the discontinued SN75518; both available from Digikey. This includes the PLCC package used in the HP/Agilent equipment.Hopes this helps someone else out there.
Snap action switch needed - Page 1
Forum section: electronics / repair

author: Grandchuck
author_rank: Super Contributor
timestamp: March 12, 2020, 05:19:21 pm
content: Limit switch, microswitch, ?The part number is 2LMT2-CAnybody? Thanks!

author: thm_w
author_rank: Super Contributor
timestamp: March 12, 2020, 10:48:16 pm
content: Its discontinued, likely you can find and equivalent by searching for size/current rating/style/etchttps://octopart.com/2lmt2-c-c%26k+components-6048089?r=sp

author: james_s
author_rank: Super Contributor
timestamp: March 13, 2020, 12:02:28 am
content: Post a picture of the switch and some basic measurements and someone might be able to suggest something. Most of the switch bodies are in fairly standard sizes but there are loads of different actuator styles.
Snap on qtech II air conditioning unit reset - Page 1
Forum section: electronics / repair

author: christopher iles
author_rank: Regular Contributor
timestamp: July 25, 2020, 03:38:56 am
content: Hello,Does anyone know the procedure for resetting this unit please?I have a blank display; I think it's a matter of taking a pin low and then powering up but have no literature.All I know is that it can be done. Any help would be greatly appreciated thank you.
Snap on Timing light - Page 1
Forum section: electronics / repair

author: mOSkit
author_rank: Contributor
timestamp: October 11, 2025, 09:07:32 am
content: Good Morning allI`m trying to repair the intermittent flash on my old snap on timing light.I found on the web the schematic related to this lamp.I would like to setup this on the bench therefore my question is: How can I trigger the the signal without the inductive pickup? I simply thinking to hook up an arduino to generate the pulse range.Page 3 is the diagram on the patent document.Thanks for any help.
Snapmaker Original Laser Module Faulty - Help Needed! - Page 1
Forum section: electronics / repair

author: gkmaia
author_rank: Frequent Contributor
timestamp: June 17, 2024, 10:43:22 am
content: :-[Hi everyone,I'm experiencing an issue with my Snapmaker laser module, and I'm hoping someone here can help me figure out what's going wrong.My laser module isn't switching to the on state when the PWM pulses are driving the laser. It seems to be stuck in Alignment Mode (Low Power Mode), and I'm unable to get it to operate at full power.Here are the details:- **Laser Module**: Snapmaker- **Issue**: The laser is not turning on to full power when PWM pulses are sent. It's only staying in Alignment Mode (low power state).- **Symptoms**:- The laser remains weak, as if it’s perpetually in focusing mode.- The issue persists across different software settings and configurations.What I've tried so far:1. Verified the PWM signal is being sent correctly from the controller.2. Replaced XL3005, R2, D2and L1I'm wondering if this could be a hardware issue, perhaps with the laser module itself or the PWM signal interpretation.I Have done a little hack to see if the laser diode is actually the issue. Seems to be as the system manages to drive the LED train.How would I choose the new TO-18 laser diode? Most of them are 5v and as I can see, the voltages across the diodes is Min 15v / Max24v / Pkpk 8.4v.https://youtu.be/AHqdyhkSEV8
Snes colours are wierd - Page 1
Forum section: electronics / repair

author: loisel
author_rank: Newbie
timestamp: September 01, 2024, 02:34:12 pm
content: so i just used my snes for thef irst time in years but now i have a problem all the colours are messed up and from what i have heard it has somthing to do with the capacitor?btw it a europian snes pal first gen i think

author: jzx
author_rank: Regular Contributor
timestamp: September 02, 2024, 06:44:44 pm
content: I supose you are using composite video.If you have an oscilloscope, check the signal. This green vertical bar seems the chroma burst, that normally does not appears in screen, and the picture seems shifted to the right, perhaps the horizontal sync is not correct.

author: Raj
author_rank: Frequent Contributor
timestamp: September 03, 2024, 11:12:32 am
content: Can't help much with electronics of it (I've never even seen an SNES on real life, let alone ever opened it.), but legally, you are legally allowed to emulate the games of which, you own cartridges of.

author: Ranayna
author_rank: Super Contributor
timestamp: September 04, 2024, 08:44:33 am
content: Quote from: Raj on September 03, 2024, 11:12:32 amThat may be true in India, i wouldn't know, but certainly is not true in Germany.The only true legal way would not to just own the cartrige and download the game somewhere.You would have to make your own copy of your own cartridge. That would be allowed as "Privatkopie" - "private copy". You are not allowed to distribute this though.And if there is an additional copy protection on the cartridge (Wasn't there a security chip on at least some of the nintendo games?) you are not allowed to make your Privatkopie anymore, as it is not allowed to circumvent any kind of copy protection.

author: jzx
author_rank: Regular Contributor
timestamp: September 04, 2024, 12:05:03 pm
content: The NES cartridges have a protection chip, the famicon ones no.Some cartridges have ram o nvram, paging circuits, logic to enhance the graphics, audio generators somtimes. Suposedly are emulated by the emulator.I dont known in snes, but in nes the protection chip only resets the cpu if it is no present, but does not encrypt the data. Of course, if the memory is paged, you must change the pages to copy all of them.Aside, some prefer to use the real console because of controllers, nostalgia, etc. And if posible with a CRT.

author: UncleMario
author_rank: Newbie
timestamp: September 04, 2024, 05:23:36 pm
content: Hey! First time poster here. I am dyslexic so please ignore any spelling errors. You can get all kinds of video issues with dirty contacts on both the cartridge and the plug in video connector.Get a q-tip, and some 99% Isopropyl alcohol. dip the tip of the q-tip into the alcohol and run along the gold contacts on the cartridge and the SNES. You should see some dirt or dust on the q-tip if it is really dirty. This helped me when I had video issues with my NES.Also, This could be a monitor configuration problem or an issue video chip/circuitry like user jzx posted. Plug it into an older CRT TV or another known working monitor.
SNES with black screen: capacitor replacement and component identification - Page 1
Forum section: electronics / repair

author: agent_power
author_rank: Regular Contributor
timestamp: August 23, 2022, 07:47:17 pm
content: Hi communityI'm in need of your expertise again. My trusty SNES that I owned since childhood has developed a fault where it doesn't output a video signal over the multi-av output anymore (but it does via RF out).I opened it up and noticed capacitor juice near some of the caps around the video output. Apparently after some googling C59 (on the SNSP-CPU-01 board which I have) is supposed to be a bipolar capacitor.I'm going to replace all the surface mount electrolytics, but there is another issue:On the other side, a component called DA18 has blown. I'm no EE, therefore my question: what's a DA designated component? I imagine this is what's causing the video output fault?See attachment for the blown component. Any help which part I need to replace this with is appreciated.Thanks!https://console5.com/techwiki/images/f/fc/PAL-SNES_Schematic.pdf

author: james_s
author_rank: Super Contributor
timestamp: August 23, 2022, 08:23:16 pm
content: I've never seen a DA reference designator before but they are probably either transistors or diodes. One of the nearby parts has "9D" stamped on it which crosses to a list of stuff, a likely candidate being PLVA659A, a zener diode in a SOT23 package.

author: Manul
author_rank: Super Contributor
timestamp: August 23, 2022, 08:29:42 pm
content: According to schematic it is a dual diode (common cathode) DAN202. You can actually buy them from distributors. "DA" might stand for "diode analog"? Not sure. It is hard to guess what other damage there might be. My guess that there will be more components damaged. Also some PCB vias look black, possible corrosion there. But you can start with diode replacement (buy more, not just 1).

author: fzabkar
author_rank: Super Contributor
timestamp: August 23, 2022, 08:55:16 pm
content: "DA" = Diode Array ?

author: agent_power
author_rank: Regular Contributor
timestamp: August 24, 2022, 07:22:31 pm
content: Hi allthanks for your replies! I cleaned up the board from the corrosion and replaced the capacitors with non surface-mount capacitors I had in my spares box.The broken dual diode measured ok, so I attempted to power the SNES on and it works again.I imagine the diode's life has been shorted though so I'd like to order some spares in case it breaks later.Is this the correct one? I noticed that there's different types. The one in the SNES have A6 printed on them, but I don't think it means anything.https://www.reichelt.com/it/en/switching-diode-sot-23-70-v-bav-70-dio-p219179.html?r=1
Soar MS-3015 oscilloscope service manual needed - Page 1
Forum section: electronics / repair

author: raymond008
author_rank: Contributor
timestamp: June 02, 2023, 12:50:33 am
content: Hi,I picked up a vintage oscilloscope really cheap - Soar MS-3015.No power, no trace. Something is wrong with the power supply area.I am looking for service manual and/or schematic about this scope.Anyone has any technical information about it?Thanks.
Socket identification required - Page 1
Forum section: electronics / repair

author: Jarek
author_rank: Regular Contributor
timestamp: December 14, 2023, 02:04:36 pm
content: What kind of socket is this?Where can I buy this ?

author: Swake
author_rank: Frequent Contributor
timestamp: December 15, 2023, 03:53:27 pm
content: Those pics only show the back of the connector. What does it connect to what?

author: Jarek
author_rank: Regular Contributor
timestamp: December 15, 2023, 09:24:04 pm
content: Socked is in the sdr Radio Flex.

author: coromonadalix
author_rank: Super Contributor
timestamp: December 15, 2023, 09:33:26 pm
content: have you sent a mail to the company about the part ?

author: Jarek
author_rank: Regular Contributor
timestamp: December 15, 2023, 10:00:07 pm
content: Not yet, but I suspect they will want me to send it to them for repair.In my case, shipping costs will be around $400 both ways.

author: Jwillis
author_rank: Super Contributor
timestamp: December 15, 2023, 10:24:31 pm
content: It's a FPC connector. As you can see it has 6 position then 10 blank and then 14 position. So a 30 position with 10 positions omitted. Probably proprietary. If the socket needs replacing then see what the pin pitch is. You might be able to replace with a 30 pin FPC and ground the 10 positions not used.

author: Swake
author_rank: Frequent Contributor
timestamp: December 16, 2023, 08:59:13 am
content: I only see 3 empty positions between the 6 and 14 wired. That makes it 23, which seems a weird number but is absolutely available. If you search for "fpc connector 23pin" you'll find plenty.When buying the connector, ensure you select the correct contact position, top or bottom.

author: Swake
author_rank: Frequent Contributor
timestamp: December 16, 2023, 09:01:40 am
content: This might fit. Has a 0.5mm pitch.https://www.aliexpress.com/item/1005001584582856.html

author: Jarek
author_rank: Regular Contributor
timestamp: December 17, 2023, 11:42:25 pm
content: Hello everyoneThank you very much for your suggestions.Unfortunately I need the original socket.
connector 40 pin FPC/FFC pitch 0.4 mm - Page 1
Forum section: electronics / repair

author: mcgaiver
author_rank: Newbie
timestamp: March 06, 2025, 11:29:49 am
content: Good morning all nerds. This is my first post on this forum. I'm from ItalyI hope you correct me if i speak you as a dogI'm stay to repair the SONY handycam FX7 and when i disassembly it, i broke the flat port that is unfindable. Someone help me to tell me where i can purchase it for a few money?I have tried to find on aliex... but there are only 39 and 41 pins. Not 40.The port is thisbut if it is possible i want to replace it with this port, because i think it is more hard respect the before connector.Thank you for your time

author: coromonadalix
author_rank: Super Contributor
timestamp: March 06, 2025, 02:04:37 pm
content: are you sure it's 0.3" we have 1mm 0.5mm ? never heard of 0.3mm do you have a caliper ?and you have the top pins or bottom pins ...or what they call forward and reverse

author: mcgaiver
author_rank: Newbie
timestamp: March 16, 2025, 07:28:12 pm
content: the port is about 16 or 17 mm

author: pcprogrammer
author_rank: Super Contributor
timestamp: March 17, 2025, 07:54:34 am
content: Quote from: mcgaiver on March 16, 2025, 07:28:12 pmHappy to correct your English. What you are looking for is called a connector.Like coromonadalix I also only know of 0.5mm and 1mm types of these connectors, but it seems there are also ones that have both top and bottom connection. The Tang Nano 20K seems to use such a connector.But yours does look smaller based on your measurement. Instead of 0.3 it is more like 0.4mm. (16/40) A google search does show that 0.4mm pitched cables seem to exist:https://www.amazon.com/Proto-Advantage-FPC040P070-Connector-Pitch-Adapter/dp/B097W5TQLDand even 0.3mm:http://www.proto-advantage.com/store/product_info.php?products_id=3400004I could not find the connectors though.Edit: A better look down the google results gave me this:https://ele.kyocera.com/en/product/connector/fpcffc_connectors/6287/The problem might be where to buy them for cheap.From the picture it seems that you broke the plastic insert to clamp the cable. You might still be able to use it though, depending on what is left of that plastic bit. Insert the cable and carefully put the plastic bit back in.

author: mcgaiver
author_rank: Newbie
timestamp: March 31, 2025, 08:14:44 am
content: The problem is that the beige plastic headquarters broke where the black tongue is housed.
Socketing a DAC? - Page 1
Forum section: electronics / repair

author: Photoman
author_rank: Regular Contributor
timestamp: October 19, 2020, 06:36:30 pm
content: Hi,I was wondering what the consensus is on socketing a DIP DAC?I am repairing a board with an oldie, AD7538 14 bit DAC. As a just in case, id like to socket it in case it fails again.I bought some pin turned gold flash coated sockets. Basically im wondering if that will change anything.On that theme, same for a AD713 op amp and a AD586 precision 5v reference.I wanted to change out the 5v reference for a higher stability one and see if it makes a difference between the 2.I just don't want to keep subjecting the board to desoldering and resoldering the chips if I can avoid it.Thanks for the help!

author: coromonadalix
author_rank: Super Contributor
timestamp: October 19, 2020, 07:16:39 pm
content: gold plated socket are good against oxydation, putting the chips on the socket is okay, but if you plan to remove them many times, you will create some wear

author: Photoman
author_rank: Regular Contributor
timestamp: October 19, 2020, 11:28:01 pm
content: Thanks! My goal (famous last words) is only once or twice.Im more concerned with affecting the op amp or the dac with maybe a whiff of extra capacitance or resistance.

author: oPossum
author_rank: Super Contributor
timestamp: October 19, 2020, 11:56:04 pm
content: Use machined pin sockets if you want the highest reliability. More secure mechanically and much less likely to have problems with contact resistance over time. Make sure pins are well aligned before pushing the chip into the socket.

author: Haenk
author_rank: Super Contributor
timestamp: October 20, 2020, 08:48:33 am
content: I'm currently ripping apart some high end audio measurement system (25 years old and limited to 500Hz-20kHz by software, so unfortunately not useful) - the ADC is socketed, the two DACs (AD1862) are soldered.Since the manufacturer used only the very best parts available (Jensen audio transformers etc. pp.) and presumably knew what they were doing, it might have been a better choice (noise-wise) to solder them directly.As the resolution of this 20bit DAC is much higher than your 14bit DAC, noise might in fact not be a problem, so I'd just use a socket. (I know I will use a socket for mine, once I get them desoldered - a true pain with a multilayer PCB and some groundig planes...)

author: wraper
author_rank: Unknown
timestamp: October 20, 2020, 08:55:00 am
content: Quote from: coromonadalix on October 19, 2020, 07:16:39 pmUnless IC pins are gold plated as well, advantage is dubious. And if IC is tin plated, most likely is worse than tin plated due to connection of dissimilar materials.

author: Photoman
author_rank: Regular Contributor
timestamp: October 20, 2020, 08:03:20 pm
content: Thanks everyone for the help. I will start my repairs with the machined pin sockets that just arrived from DigiKey.Now to figure out the cause of the failure....
SOIC 8 pin Package Quick Release SMD Socket - Page 1
Forum section: electronics / repair

author: 2X
author_rank: Frequent Contributor
timestamp: May 10, 2024, 11:09:28 pm
content: Hello,do you know where can I find this socket or his name to search it?https://www.google.com/search?sca_esv=b2746cf197726f04&udm=2&sxsrf=ADLYWIJHv2tFiz5X8zJoYKUsXm6axMKydQ:1715381775047&q=SOIC+quick+release+socket&spell=1&sa=X&ved=2ahUKEwiEguyKl4SGAxUuAdsEHQj8AX8QBSgAegQIBxAB&biw=1920&bih=911&dpr=1

author: abeyer
author_rank: Frequent Contributor
timestamp: May 10, 2024, 11:18:56 pm
content: "8 pin BIOS socket"

author: jpanhalt
author_rank: Super Contributor
timestamp: May 10, 2024, 11:22:30 pm
content: 3M Textool (https://www.3m.com/3M/en_US/p/d/b00035242/) are made in various sizes. You will find cheaper copies, some of which use that name, on eBay. They are not exactly what you show, but they are ZIF, and I have used them for programming.

author: 2X
author_rank: Frequent Contributor
timestamp: May 12, 2024, 07:17:29 pm
content: Thank you very much both of you.
SOIC 8pin - Page 1
Forum section: electronics / repair

author: ksb
author_rank: Contributor
timestamp: July 19, 2021, 12:55:20 pm
content: Can someone help me to identity the exact part for the ic in the picture?

author: mbno
author_rank: Newbie
timestamp: July 19, 2021, 01:14:40 pm
content: That looks like a Texas Instruments SoundsPlus Audio Op Amp OPA1642AID. Looking at the datasheet it has the marking "O1642A" and comes in a SOIC package.https://www.ti.com/lit/ds/sbos484a/sbos484a.pdf

author: TheMG
author_rank: Frequent Contributor
timestamp: July 19, 2021, 01:14:46 pm
content: Texas Instruments OPA1642 opamp

author: ksb
author_rank: Contributor
timestamp: July 19, 2021, 01:56:58 pm
content: Thank you for giving me this information.

author: fzabkar
author_rank: Super Contributor
timestamp: July 21, 2021, 07:02:47 pm
content: https://www.ti.com/packaging/docs/partlookup.tsphttp://www.smdmark.com/en-US/search/code?id=o1642ahttps://ipv4.google.com/search?q=filetype:doc+OR+filetype:pdf+"absolute+maximum"+01642a+OR+o1642a