Questions relating to electrical / electronic repair. Please ensure your questions are somewhat generic in nature so they are likely to help future visitors and not too localized to a specific piece of equipment.
-1
votes
0answers
57 views
VGA capacitor issue [closed]
I recently bought an aftermarket cooler for my GPU and long story short, it set my GPU alight.
There seems to be damage just behind the PWM connector where the small fire was, only 2 surface mount ...
0
votes
1answer
61 views
Repair a xbee wire antenna?
last year I bought a xbee pro s2b, the wire antenna one. After some use, the antenna started to loose, and last week it just broke. Is there a way to repair it? I soldered it again, and it holded some ...
1
vote
3answers
80 views
Identifying SMT element 331K
I am trying to repair a remote from a car lock. The symptoms are that a red led is lit longer than usual after button press and no respond from car lock. It works sometimes. The battery and ...
-1
votes
3answers
112 views
Wires resistant to frequent bending for use in headphones
I'm tired of continuously fixing wire on headphones.
Can you recommend good wire that resistant to the frequent bending and thus will be last ultimate replacement as headphone wire ?
-2
votes
1answer
87 views
replacing plug on headset with volume control
I have a pretty expensive set of philips headphones with a volume control on the lead that lost sound in one ear, I couldn't fix it and keep the original plug.
Having removed it, I'm at a loss as to ...
0
votes
0answers
105 views
2.1 sound system noise
I have a 2.1 small sound system that makes a high frequency noise when turned on, whether the input is grounded or not. I've opened it and measured the frequency of that noise with a scope and it is ...
-1
votes
1answer
46 views
Weller WRS3000 Airflow Problem
I inherited this repair station from my job, it was deemed no longer worth keeping since it isn't working. I have gone through the manual and reset the unit to factory conditions, and everything ...
0
votes
2answers
102 views
How to fix a broken Sharp CD-BA150 stereo with the help of a service manual? [closed]
I have a Sharp CD-BA150 stereo. Since the cd and tape decks are completely busted (doesnt play, rewind, etc.) and I have nothing to lose (I plan to throw it out anyways) I want to try to repair it ...
2
votes
5answers
119 views
Want a Second Look Do all of these Capacitors Need to be Changed? [closed]
I pulled apart my monitor to check the capacitors and I think almost all of them need to be replaced but there are a couple I am not sure about
13
votes
4answers
555 views
Wire broke off and stuck in a header
I'm working with an Arduino, and one of the stripped portions of the wire broke off at some point and managed to get pretty wedged into the 5V pin slot. Obviously, this wouldn't matter as much for a ...
0
votes
2answers
127 views
Date of introduction of TO-92 transistors
I'm trying to date a circuit from an organ. It contains transistors in a TO-92 (plastic) package.
Approximately when did these transistors first appear?
3
votes
1answer
137 views
RFID coil - ends broke, can I resolder?
The 125kHz RFID scanner / reader device I have, has a coil like this:
NB> Don't have a good camera handy at the moment, so had to share a cropped image from Alibaba, but the pic is very close to ...
0
votes
2answers
165 views
Repairing resistors [closed]
I'm attempting to repair a resistor that was physically damaged by a heavy object. The part is a Yageo CFR-25JB-52-10K and the datasheet may be found here. I've attempted to use Loctite Epoxy Instant ...
2
votes
1answer
142 views
How to find a replacement MOSFET
I have a small, dead power supply for a camera battery charger (cheap replacement, no brand name). I opened it up and discovered that one of the MOSFETs is burned out. The datasheet (in chinese) is at ...
4
votes
1answer
268 views
Resistor in series with primary side of transformer failing
I was given a Trio CS 1554 Analog oscilloscope. It hasn't been turned on for at least 2 years, but probably a whole lot more.
Today I plugged it in and it turned on. It was usable for approximately ...
0
votes
1answer
118 views
Replace Expensive Transformer with cheaper alternative? [closed]
I have a range hood that has an expensive (IMO) transformer that has went bad. Here is the link to the transformer that went bad: ...
4
votes
1answer
254 views
A good technique for removing 50-pin SMD CF/MD card slot with Hot air
I have a piece of equipment that has a CF/MD card on it. Somebody tried to force the card in and broke 2 pins off. I managed to replace the two pins temporarily, but it was kind of a hack job, but it ...
-2
votes
1answer
225 views
ATX power supply troubleshooting [parttern of failure] [closed]
I'm troubleshooting a ATX power supply and I found that fuse has gone.
Then I replace the fuse, Then fuse burnt very violently. Then I trace the tracks and
found that RL207 diodes , 3 out of those 4 ...
7
votes
3answers
283 views
Sensibility and health hazards of reflowing computer PCBs in a domestic oven
This is a bit of a fringe question, SE-wise, but I think EE is the best place to ask it.
Some acquaintances of mine had a problem with their laptop - the graphics card stopped working. They've ...
1
vote
3answers
454 views
How to safely discharge high voltage (> 42 V) capacitors?
I have a 1200 watt PC power supply (yeah that's for a gaming rig!). Unfortunately it's failing on me after about 3 years. As the guarantee is over and I don't want to have shipping costs, I want to ...
0
votes
0answers
165 views
Replacement for 5610 Transistor
I have a circuit (from a RC car) that uses a 5610 transistor, which can't find in store.
Is there any equivalent transistor?
Here are pictures of the board (click here for high resolution images):
...
3
votes
1answer
125 views
Advice needed for replacing old ER3055 transistor
I have a transistor in a guitar amp with the label ER3055 that needs to be replaced. I asked about another transistor that I needed to replace in a post a few days ago here and I tried using NTE to ...
1
vote
1answer
109 views
Is it possible that a new transistor is not good even if a current runs through it?
I just got an NTE121 replacement transistor for an old 2N2148 that was in a guitar amp. It was the only part I replaced and now I have no sound coming from the speaker. I checked every component on ...
5
votes
1answer
168 views
How to find a replacement for an antiquated transistor 2N2148
I need to replace a transistor in my guitar amplifier. The model number listed on the original schematic is 2N2148. It is in a TO3 package and the rest of the specs are listed here.
I am having ...
2
votes
2answers
260 views
In this project, where does the rectifier go?
I was a backer of an early Kickstarter project, and now the project leads have dissapeared. Before they left, they offered some advice to fix some of their faulty units. Here's a picture of the ...
-1
votes
3answers
277 views
Olevia model 237-T11 TV won't turn on [closed]
So my Olevia model 237-T11 tv stopped working the other day. Now mind you, I tried everything from unplugging, waiting 30 minutes, replugging it into the outlet, using different power outlets, etc. ...
-2
votes
1answer
181 views
Can I change the capacitor from 1uF 2000 volt to a 2uF 2200 volt? [closed]
I am facing a problem in a pipe welding machine circuit. In this circuit one transformer the in put of this transformer is 400V 3.4kVA and outputs 12V. After this 12V, two capacitors (1uF 2000V) in ...
0
votes
2answers
126 views
Finding Failed Component in broken florescent lantern circuit
Recently, I burned out the circuitry in a florescent lantern by accidentally reversing the polarity of the volts in. The circuit seems pretty simple, a transformer, 3 resistors, 3 mono capacitors, a ...
0
votes
3answers
1k views
Replacing (and perhaps upgrading) bad capacitors within a speaker system?
A few months ago the volume of the left speaker of my pair of low-cost audio monitors began slowly diminishing. Every day it seemed to lose a fraction of it's normal operating volume until the speaker ...
-2
votes
1answer
201 views
Indetifying burnt components [closed]
I have been far from electronics lately, but a related problem has appeared at work and I had to take a look.
So: somebody screwed up and burnt input components of two devices: an expensive ...
14
votes
3answers
498 views
Why the arc when bonding-on during high voltage repairs?
When working on high voltage power-lines via helicopter the technician will "bond-on" with a steel wand called a hot-stick. During this process an arc is conducted from the line to the wand. Now, ...
0
votes
2answers
1k views
Fixing/Replacing Conductor Ribbon Cable
I tried to fix a keyboard that was having some intermittent issues by cleaning the conductors on the ribbon cable. I used an emery-board to rub off the rust and patina on the pins at the end of the ...
3
votes
1answer
95 views
Safely testing a DC supply with an unknown output configuration
This picture shows the connector for the DC end of a power supply I extracted from a dead HP MFD (Multi Function Device):
As you can see it consists of 4 pins in a 2x2 configuration. The sockets ...
1
vote
1answer
172 views
How do I choose the right replacement fuse for my multimeter?
I have a BK Precision 2709B Multimeter. I managed to blow the uA fuse (500mA/500V fast blow ceramic) on it. Is it an ok to replace this fuse with a 500mA/1kV fast blow ceramic fuse? What impact would ...
11
votes
4answers
534 views
Choosing my first oscilloscope
I'd like to repair older computers, such as C64's, Atari's, Apple IIe's etc and their power supplies. I have a multimeter already but I'd like to get an oscilloscope. I've been offered an Owon ...
2
votes
2answers
196 views
Are there any dangers to consider when replacing a permanent AA NiMH battery?
The battery in my electric razor has failed to charge for several years. It does not turn on unless I leave it plugged in for 20 minutes and it turns off immediately if I unplug it. To save some ...
3
votes
3answers
346 views
How to diagnose and repair a radio?
A friend gave me a Marine VHF Radio Receiver which is working badly, and asked me if I can look into it and try to repair it (I'm not going to charge him).
The first time the radio is turned on, the ...
9
votes
3answers
419 views
Cleaning Circuits with Compressed Air
I've been arguing with a colleague whether it is a sensible solution to clean dusty PCBs with compressed air. While I think this is the best solution (nothing touches the PCB), he claimed that ...
1
vote
2answers
189 views
How to fix a broken sub connection and wire?
The wire connecting to my sub has snapped off, and it brought the metal connector piece with it.
I don't want to buy a new sub, but it looks like this is going to be hard to repair. Anyone have ...
2
votes
2answers
377 views
Weird failure: Loud Sweep Tone on SMPS, ideas?
my brother has an old mac computer that didnt work, so he asked me to fix it, its one of those macs from the early 90s, a Macintosh Classic II.
So i opened it up and i found electrolyte all over the ...
1
vote
2answers
495 views
Replacement Transistor for Ultrasound Cleaner
I'm trying to repair the generator board on a Sonix IV ultrasound cleaner. I need to find a replacement for a transistor (in a TO-3 package), but the manufacturer uses an in-house part id, so I'm ...
-6
votes
3answers
221 views
Powering Laptop internal monitor
So I have a problem with my old laptop. Internal monitor is not working. External is working.
So I tried to understand what's the problem.
I tried to check if inverter is broken. It get's a good 19V ...
3
votes
1answer
1k views
Fixing APC UPS buzzing noise
I have an APC UPS and one of the caps - an SIEMENS EPCOS 20uF 150V Capacitor - started making a buzzing noise.
This seems to be a AC, non-electrolytic capacitor and most local stores have it priced ...
0
votes
2answers
653 views
Transistor Replacement
I have dell laptop D600m. I have a charger for it but the charger does not work properly meaning that it can power the laptop but does not charge the battery of the laptop.
I opened the charger and ...
1
vote
2answers
588 views
Repair a ripped touchscreen cable
I have an Ampire AM800480STMQWT00 touchscreen display. In the course of testing the device, the cable for the touchscreen proper got ripped by accident.
Is it possible at all to repair the cable ...
1
vote
1answer
693 views
Repairing a digital multimeter?
don't know if this is the right place to ask such a question but i'll try.
I opened up my DMM to check fuses. Now I would like to close it but before I can do this I have to put in the right place the ...
4
votes
2answers
112 views
Testing an old Geiger tube?
I have an old Soviet personal radiation dosimeter that I broke as a kid by dropping it into water. I opened it up a while ago and the electronics in there were quite simple - mainly a ~10cm Geiger ...
2
votes
0answers
214 views
Fixing a blown oscilloscope? [closed]
I recently bought an old Philips PM3340 oscilloscope from eBay.
I used it for a few minutes to look at a clock signal, and it was working fine. Then I heard a noise from inside, and saw a cloud of ...
1
vote
1answer
260 views
Programming Xilinx XC9572
Can I read and save the program from a Xilinx XC9572 and burn it to another blank DC9572? I have a Needhams EMP30 which has this device on its list. I need the adapter for the PLCC 44 pin to DIP. But ...
4
votes
3answers
2k views
Detect damaged SMD capacitors
How can I easily find damaged SMD capacitors without removing them from the PCB? I want to repair my laptop's graphics card (ATI Mobility Radeon x300). I have done a visual inspection of the board and ...
