- Peavey XR684 mixer amp - 1 Update
- Looking for a tube only radio or radio kit - 2 Updates
- Source for LED backlight strips? - 1 Update
| N_Cook <diverse@tcp.co.uk>: Jun 24 12:45PM +0100 I swapped the speaker leads over on the outlet pcb and the same 2 output transistors heated up , so verified not a crowbar problem. First guess (1 to 2 sec timing) its a problem with or associated with one of the 22uF 50V caps in the splitter section. At least with no minor supplies connected , its not an preceeding op-amp problem. |
| Micky <NONONObobbyburns1111@gmail.com>: Jun 23 05:01PM -0400 On Mon, 20 Jun 2016 07:16:28 -0700, Bennett <bjprice@cal.berkeley.edu> wrote: >V1, V2, etc.) >Since the plastic case never needs feeding there is some slight >likelihood of a translation problem. http://ebay.to/28J5Lw7 I noticed that, but that's good. It means I can go out of town without worrying who is feeding my case. |
| Micky <NONONObobbyburns1111@gmail.com>: Jun 23 05:07PM -0400 On Sun, 19 Jun 2016 17:44:59 -0700, Bennett Price >Schematics, assembly drawings, and the other parts list, technical >documents are complete. >Despite the description, it uses transistors, not tubes. It also says Power: 3V (5 batteries) That seems interesting. |
| "Kenny" <me@privacy.net>: Jun 23 06:16PM +0100 "Kenny" wrote in message news:bpednS2QIckHFqLKnZ2dnUU78dHNnZ2d@brightview.com... "Ian Field" wrote in message news:wAo%y.847680$8r2.99354@fx46.am4... "Kenny" <me@privacy.net> wrote in message news:NNKdncuibJTgI6fKnZ2dnUU78WHNnZ2d@brightview.com... > Looking for a reliable UK supplier for these. I don't have a part number > but have the panel type number, it's in a 50" LG TV. My experience with this was finding a TV in the flats bin room that was made by a well known Turkish company (Vestel). Apparently LED failure is one of a long list of stock faults..................................... Unfortunately I cracked the LCD panel putting it back together, but I learned a fair bit from the excercise. Each LED had a plastic lens extruded on, I had to melt these with a soldering iron to peel them off. The iron wouldn't shift the SMD LEDs. It took a modeler's pencil blowtorch to shift the dud LED chips, after that I used a small roll of emery paper to clean off some solder resist and attach some power LEDs I had to hand. You can re-touch the PCB around the replaced LEDs with correction fluid. If its a Vestel - you'll probably find a few more LEDs that tested OK have given up.............................. https://www.youtube.com/watch?v=Bf5T2wwtydY This is the video I watched, it's for a 47" LG, mines 50", I don't have the space to work like that and wouldn't feel confident dismantling the screen anyway. Local shop say they'll look at it and give me an estimate so that's probably what I'll do, thing is this TV is only 2 years old and the same fault may recur. I've decided to buy a 55" Sony with 5 year warranty and giving the LG to a family member if they want to pay for the repair. Update on this, was very careful dismantling the screen and using a variable power supply found a duff LED on 2 of the 12 strips. Easily found using the part no. on them, expensive at £25 each. I've reduced the backlight current to hopefully make them last longer, it seems LG set the default at maximum! It wasn't as difficult as I had expected and if doing it again I'd try replacing individual LED's, I have a few spares now. |
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