I was thinking... we should have a thread with documented repairs. Lots of times when I'm working on something, I posts of other people online who have the same problem but rarely a good explanation of the fix. Badcaps is the place to go for caps problems... why not repair journals? If we do it right, they should show up on Google.
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Technics SU-G91 Overload
Problem: Technics SU-G91 Stereo Amplifier. Overload protection will kick in as soon as you start cranking the volume, or sometimes as soon as you turn on the amp. Severity of the issue varies.
Cause: Bad solder joints on the two Amp Packs mounted on the heatsinks inside and everything around the heatsinks, causing Amp Packs to malfunction or, in my case, the fan to not turn on.
Solution: Resolder all connections on the amp packs (black things on heatsinks) on the mainboard and the daughterboardNow find where the fan plugs in. Follow the traces and resolder the network of resistors and 3-pin devices immediately in front of the heatsink. Resolder everything on the other side of the heatsink next to the amp pack. There is a trace coming from the network connected to the fan connector that ends on the side of the heatsink with the amp pack. Make sure you resolder that.
Put back together, crank it loud, and enjoy. -
JVC C-2019 Loud Buzzing Sound
Problem: JVC C-2019 20 inch color TV. Nice TV. Works, but makes a LOUD buzzing sound whenever turned on, sounds like an electric motor.
Cause: C791, a 4.7uf 350v capacitor near the relay, has dried out causing the relay to make the loud buzzing noise. Do not operate the TV in this condition until you fix the problem.
Solution: Replace C791.Comment
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Neoware Thin Client model BA-EON5000T
Problem: Neoware NT Thinclient. power light flashes and unit clicks when powered up. Will not boot OS.
Cause: internal power supply without vent fans or vent holes in unit case.
Solution: replace bad capacitors in the power supply
1000uf 6.3v (x4)
470uf 10v (x2)
220uf 25v (x1)
and purchase plenty of replacement capsLast edited by pflowers; 02-07-2009, 04:22 PM.Comment
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Re: The Electronics Repair Thread
Problem: Sony STR-AV970 Intermittent display failure, intermittent pops and clicks, intermittent tuner failure, intermittent microcontroller related funkyness.
Solution: Rework about half the solder joints in the unit on multiple boards, reseat all the boards and make sure the grounding screws are tight.
My friend now has a good secondary stereo.... for $0 and 4 hours of labor.
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Howdy folks! I'm an artist in the video game industry, and my job entails making a lot of mechanical and sci fi assets. I thought it might be a good practice to start disassembling some electronics to be more familiar with how real electronics are manufactured and assembled, which is how i found my way to these forums.
When I started researching what tools I might need, I quickly encountered the warning "Some devices can maintain a potentially lethal charge in their capacitors, even up to years after last being powered on", which was enough of a scary thought for me to... -
Hello,
I've got a really strange issue with the speakers on my Philips 43PUS7506/12. It makes this awful loud buzzing now. It happened after it was attempted to be wall mounted - I think the back got squeezed and something broke.
I thought maybe the speakers got damaged, so I replaced them - no dice.- Using the internal speakers, it always happens.
- Using the headphone jack, it never happens.
- Using the digital/optical out with a soundbar - it happens after about 2h/movie runtime - it's never as drastic, it just pops in and out, but I didn't want it to damage the sound bar
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I have a question since I am new here and I don't know if this is the right forum to ask these questions or if I am wasting your time.
I am 67 and have a lot of Radios and Electronics I grew up with which puts a lot of them at 50 years or older.
A lot of the capacitors are obviously bad but this is my problem.
An example would be the Panasonic RC-7469 Clock Radio and the Panasonic RF-888 Radio.
I have others like a Canon L-162 Nixie Desktop Calculator 110AC, etc.
I have the Service Manuals to some of these and other electronics I have and grew up with and... -
Good evening team,
I've been trying to learn electronics since the beggining of the year. My main goal is to fix broken consoles/laptops. It has been a very fullfilling journey and fortunately I've found my way around and I've already fixed a few of them.
While there's a lot of info online (this forum as an example) I would like to gather a few suggestions about books on electronics. I've already attempted to read a few ones, but to be honest I haven't found anyone that suits what I'm looking for. As an example "The Art of Electronics" is amazing, but there's... -
Hello guys,
recently I watched Richard's video on YT (Learn Electronics Repair channel) with an explanation why lower input voltage than rated can also kill electronics components.
The vide can be shown here.
Now, I would like to learn more and I'm not sure that I understood exactly why this is happening.
It is clear to me that PWM chip will keep MOSFTES switched On longer (duty cycle is longer) and that they will dissipate more heat. I think this is not the main reason because MOSFET can probably work switched on for a long time. It is also possible that output...12-26-2022, 12:45 AM
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