Questions tagged [repair]

Questions relating to electrical/electronic repair. Questions on the repair of consumer electronics, appliances, or other devices must involve specific troubleshooting steps and demonstrate a good understanding of the underlying design of the device being repaired. 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.

Filter by
Sorted by
Tagged with
0
votes
1answer
33 views

HP 1740 monitor stay on 2-3 seconds, turn off and repeat

I have an HP 1740 monitor that, when I turn it on, just remains 2-3 seconds to display and turns off completely (even the pilot). It seems to me that the problem is not in the backlight. I opened the ...
0
votes
1answer
43 views

Repairing power circuit with reverse polarity damage

Recently I bought an old musical keyboard (a Casio HT-3000). It came with a PSU, and when it arrived I plugged it in without paying too much attention, and... nothing but a burning smell. I quickly ...
0
votes
1answer
78 views

Where to start repairing a faulty electronic board?

I am working on electronic card repair of textile machines. When a faulty electronic card arrives, I visually check it first. Is there a burned or cracked componenet next to it, if any, I am replacing ...
-1
votes
1answer
56 views

Fixing a TV remote with a low voltage button [closed]

I'm trying to fix my TV remote (Panasonic Viera) as one of the buttons has become unresponsive. I've cleaned it with alcohol and noticed the voltage across is just 0.3V rather than 2.7V across the ...
0
votes
1answer
54 views

What's the best way to fix this missing solder pad?

During a repair of a mixer, I had to desolder the XLR output jacks in order to remove the front panel. When I started to resolder them I noticed that an pad (or eyelet? not sure of the difference) is ...
0
votes
2answers
77 views

How can I find a replacement LED to repair RJ45 tester? (re: SMD size, measured with multi-meter)

I'm trying to fix an RJ45 (CAT5/6 lan cable) tester and I need to replace some LEDs and diodes (SMD and not through-hole). The tester has 8 LEDs (one for each wire) and only a few are blown so I ...
2
votes
2answers
106 views

How do I solder a ~20-pin USBc connector near heat-sensitive components?

I currently have an LG V20 and its charging port is deteriorating. Unfortunately, it is out of warranty and the best price that I can find to have it professionally repaired is US$60, which is about ...
2
votes
0answers
35 views

2KW - 48V - 240v / 50Hz UPS - Unknown Topology

I am refurbishing a 2kw ups that a friend gave to me. It had failed and had been left in a shipping container on a site and the PCB had suffered some low level corrosion. The PCB is a 2 layer board, ...
1
vote
0answers
38 views

IC Protector in AV Receiver (ICP-N15)

I'm fixing a Denon AVR-788 AV receiver that won't boot but would turn on with the light in front blinking red. Naturally, I looked to the Service Manual (link goes to schematic) and started following ...
0
votes
0answers
35 views

Capacitor replacement on ancient Fisher & Pykel fridge - which pins to connect?

I have three pins on this compressor: [a] white wire post - live phase - bottom left [b] capacitor resister - copper terminal - top left [c[ black wire post - ground to wall - bottom right It's so ...
0
votes
3answers
47 views

How to protect a battery terminal after removing corrosion?

I have repaired a corroded battery terminal by neutralizing it in vinegar and then cleaning it with a wire brush. The result is a terminal lead which now has bare steel visible where the protective ...
0
votes
0answers
53 views

Xbox 360 Circuit Board Repair

TL;DR: Replaced faulty analog sticks with known functioning sticks on a wireless controller, but still doesn't work. Tested for shorts on the board, found them. How do I proceed with the repair? I've ...
4
votes
2answers
184 views

Mitutoyo LCD repair [closed]

Never asked on stack Exchange before, and only have very basic knowledge in electronics (mechanical engineer by trade). Can anyone suggest if the LCD on this vernier caliper is repairable? One column ...
0
votes
0answers
41 views

USB C 2 wire, how it works & Connector repair

I wanted to repair an usb cable from a charger which can output 3A max. So on my charger cable, I got 3 wires. I got another USB C cable which can support 3A (USB-A to USB-C) and it only has 2 wires. ...
0
votes
0answers
62 views

How can I identify a diode without a circuit diagram?

I have a multimeter which I have been given. It belonged to a friend whom has passed away. However I have found that it isn't working properly. Upon inspection, I have found that 2 diodes have shorted,...
0
votes
0answers
40 views

Segment LCD only viewable at extreme angles

I have a kitchen scale with a segment LCD display. Starting one day, the LCD display is barely legible at all; sometimes the numbers are viewable from an extreme angle, sometimes not at all. Sometimes ...
1
vote
0answers
65 views

via in pad, thermal via, or something else?

So recently while watching a video I came across this: to me this looks like a pad with a bunch of vias in it. I haven't encountered multiple vias in the same pad before. I tried to search images of ...
1
vote
1answer
56 views

What type of solder to use with unregulated 25W soldering iron?

I have a general purpose unregulated 25W soldering iron (soldering pencil.) What type of solder is suitable for this (melting point degrees, composition?) Mainly for simple repair work (solder ...
1
vote
2answers
56 views

Diagnose failure in LED driver

I have a number of 4 ft (1200 mm) linear LED assemblies which were replacements for fluorescent tubes. (Ballasts were removed). Three-four of these (~10%) have started to fail after 1-2 years of ...
0
votes
1answer
79 views

Identify a fried capacitor

I am trying to clearly identify a fried ceramic capacitor in order to replace it. By chance, I could take a picture on another device of the same type: So far what I found after some search: I ...
1
vote
2answers
86 views

How to find the short circuit element on electronic board easily

I have two Uster Tester ( this machine used at textile) cards. one is corrupted and the other is the same one that works. Trying to repair the corrupted card by performing comparison test. When I try ...
0
votes
1answer
92 views

Effect of submerging a laptop in isopropyl alcohol without removing batteries

It's common knowledge that water damage on many electronic devices can be mitigated using isopropyl alcohol at a high concentration. Many guides have mentioned disconnecting the battery before using ...
0
votes
1answer
55 views

Replacing brushless motor (starting) capacitor with one of a higher capacitance

My kitchen hood vent is malfunctioning, the motor driving the fan is buzzing at different intensities depending on the speed I select. I took down the unit and if I give the fan blade a spin, it ...
1
vote
1answer
86 views

Recover a board from corrosion damages

A smart device board shown various issues and stopped to power on. I have opened it to determine the cause of the problem and I have seen it has multiple corrosion signs. The board wasn't exposed to ...
0
votes
1answer
51 views

Purpose of metal sheath in display cable?

I want to repair a display cable which I suspect has some broken wires. The cable seems to be wrapped in a metallized fibre cloth. (I don't know the correct name for it). What purpose, apart from ...
0
votes
0answers
40 views

Fixing damaged flex cable in LCD display

I have salvaged an LP154WX4 LCD display from an old laptop, and I've bought a controller board on Amazon. After hooking it up, I've noticed a few vertical lines on the screen: thinking it was an issue ...
2
votes
0answers
46 views

What substance to use for removal of leaked NiMH electrolyte from PCB

I have experienced some problems with alarm siren (intermittently alarm goes off) in my car (Audi A3). After removal of siren and opening its box there are visible marks of corrosion and residues from ...
1
vote
1answer
48 views

Trying to source a PCB component (a slow blow fuse I believe!)

I’ve stumbled upon this forum in a search for a replacement part for a PCB that makes up a digital ballast for a HPS light used in basil clone production. I’m handay with a soldering iron but I am ...
2
votes
1answer
111 views

How did static charge ruin my control board?

We have a Thermia geothermal heat pump that was working fine up until we had a particularly bad thunderstorm. Lightning took out the power for a while and burned up a DSL modem, a router, and a IP ...
2
votes
3answers
205 views

Replace/refresh 7 segment display of vintage 80's clock radio

Past two weeks working on this clock radio because I love the looks of it and it is also pretty rare (it must be restored in original condition or better). Fixed almost every non-working feature such ...
3
votes
2answers
211 views

Replacing smoothing capacitors in vintage guitar amplifier without datasheet

I'm in the process of servicing my Carlsbro stingray super combo amp and whilst disassembling I noticed that one of large caps (I assume smoothing) has started bulging and leaking. Ive tried ...
0
votes
1answer
158 views

Damaged solder pads on FX-Audio DAC-X6 Alternate solder locations?

I've tried to remove a faulty 6.5mm headphone jack from a FX-Audio DAC-X6 and ended up removing the solder pads from the board. I'm trying to save this instead of trashing it and buying a new one for $...
2
votes
1answer
151 views

How to calculate impedance for reverb tank in a guitar amp

Background: I'm in the process of restoring a HIWATT HI-GAIN 50 COMBO Valve guitar amp and one of the issues it has is that the reverb dial has no effect on the sound. Attempted troubleshooting: ...
3
votes
0answers
77 views

How to reconnect to potential of ripped off solder pad without visible circuit traces

I am trying to get a data backup from a broken LG/Google Nexus 5 smartphone. It was repeating in a boot loop, because the on-switch was stuck at always on. I dismantled the mainboard. Here is a ...
2
votes
0answers
65 views

Correct procedure to identify a component and obtain the datasheet

I'm not sure what should be the correct procedure to obtain a component's datasheet starting from the component's package code. I searched in the other questions, but I found mostly people asking ...
0
votes
1answer
212 views

How to repair solar panels without being able to source an exact replacement diode

How can I repair a solar panel (replace the blocking diodes) without access to the exact same components? I have a 100 watt 20volt semi-flexible solar panel marked PV-XC502 on the junction box, ...
0
votes
2answers
66 views

Changing push-pull transistors in brushless motor driver

I am fixing a brushless motor driver that has 6 MOSFET transistors, 2 transistors for each coil. I have found that SW5 is burned so I changed it and everything now works well. However, I have heard ...
2
votes
4answers
2k views

How to best clean this sealed mechanical rotary encoder / volume knob?

How can I best clean, replace or lubricate this fairly well sealed digital rotary mechanical encoder? The equipment operates, but the encoder is super finicky, often encoding in the wrong direction ...
0
votes
1answer
89 views

Replacing Projector Fan - Wiring Color

An old Sony VPL-CX11 stopped working because one of the fans (the lamp's one) was so rusty that couldn't rotate. In the front of the projector there are two fans, one for the lamp and the other for ...
0
votes
2answers
107 views

VI component tester not working properly when capacitor is placed parallel with diode

I am trying to repair mainboards with VI component tester. (Such as this device and that device.) I check the characteristic VI curves of the components on the card and identify the defective parts ...
0
votes
1answer
52 views

Mosfet testing for short from youtube repair video

In the 23:40 of the youtube video https://youtu.be/YQ7SXJqIpzs , the presenter does a p-channel mosfet test for short, using his bench power supply on the circuit. From what i understood, he ...
1
vote
1answer
394 views

RIFA PME271M547 replacement

I just broke my sewing machine (it's an old Viktoria machine about 30-40 years old) and now I am looking for a replacement safety capacitor. The one installed is a RIFA PME 271 M 547 paper capacitor. ...
1
vote
2answers
227 views

Clean/repair/replace the carbon pill of a rubber keypad

I have several devices (calculators, remote controllers, …) with rubber keypads where some keys are dysfunctioning. As I understand it, this is because of the carbon pill since things work fine if I ...
3
votes
0answers
104 views

Bluetooth speaker works only when aux is plugged in [closed]

Plot Recently got this Bluetooth/FM speaker with a built-in microphone from my friend to try repairing it. He said that it's battery was swollen up so he dumped the battery and never used the speaker ...
1
vote
0answers
75 views

DC permanent magnetic motor control issues

We have a 180 V dc permanent magnet motor. When engaging the control board while the motor is hooked up. The output to motor drops out and reads no voltage. If I take the motor leads off the ...
1
vote
3answers
130 views

solder-bridge at ribbon-connector?

I am currently trying to repair a pen-tablet-monitor, which has what i call a 'blind/dead row'. Meaning that i can draw everywhere, but there is this one row, where any input is either picked up by a ...
-1
votes
1answer
131 views

Subwoofer amplifier IC repair? [closed]

I bought a subwoofer as is. The sub worked, but the speaker terminals didn't. I took a look inside and the amplifier IC(TDA 7265) looks like it shattered somehow. Any ideas what could have ...
12
votes
1answer
307 views

Troubleshooting a faulty filter circuit in a PAL CRT display

I have an old CRT monitor (Phillips CM8833) which I am attempting to repair. When displaying a composite PAL signal, it only shows a black and white image, but it is still able to display RGB signals ...
2
votes
3answers
439 views

Soaking phone motherboard in isopropyl to fix potential corrosion

Is it advisable/safe to soak my phone motherboard in an isopropyl alcohol bath? I dismantled it after water damage occurred and it now powers on fine but my cell signal isn't consistent. I was ...
0
votes
0answers
135 views

Insights required to repair my Agilent YIG oscillator

I know, it's probably no chance. But let me try. The model is HP-Agilent 0955-0520, Y088-4258, that can be bought for 600-900$. Here is a picture. When I bought the oscillator, I performed multiple ...

1 2 3 4 5 6