dicky96
New User
Mar 28, 2017, 12:34 PM
Post #1 of 1
(1002 views)
Shortcut
|
|
New Member with a Question re: LG 32LN520B won't power up
|
Can't Post
|
|
Hi Guys
So I'm new here which probably means a little background info first would be a good place to start
I'm from the UK and I've been an electronics hobbyist on-and-off all my life since age about 14
I'm certainly no beginner with electronics.
I got my City & Guilds way back in the 80s in 'Video TV & Electronic Servicing' when some TVs still had valves in them!
Never fixed TVs for a living as I went straight to work for International Computers in their repair workshops for seven years. In the 90s I also worked in Industrial Electronics repair for a couple years. Also got qualifications in Microprocessor Circuit Design & Programming and worked as a programmer for a few years.
Much more recently I have been repairing Disco Equipment (Amps, Mixers, Lights Lasers etc) as a side line
So basically that is about me - just so you know if you advise me I will probably understand what you are telling me and be able to apply that advice
Now I have moved to Gran Canaria and, wanting something else to occupy my time other than lying on the beach, I found folks round here have lots of electronic stuff and no one to fix it so I am trying to lend the other expats a hand and make a few euros while I am at it. I'm not doing this as a job, just a side line.
I brought some of my kit with me so have various meters, digital scope, bench PSU, through hole and SMD rework station and toolkit here. At least the basics of what I need to do some jobs. Left the heavy stuff (Mains isolation transformer, Variac and my trusty Techtronix analog scope) back in the UK for now.
OK so enough background.... right now I have this LG 32LN520B TV here and I have no experience of flat panel TV repairs!
PCB is marked LD36M
When I plug in the 24V PSU, the little red LED by the power button lights up, dims, lights again, dims once more then goes out.
That's it. The TV will not power up and does not respond to the on/off power button.
Quick poke around the PCB (with my meter not my fingers fortunately!!) found 24V supply on the input cap, and 120V across a couple other electrolytics the other side of what like a big square filter or inductor and a power FET. The 120V slowly discharges when I pull the 24V power supply.
So there is power in there, it just ain't starting up.
Any advice from you guys on how to diagnose this further?
Cheers, Rich
|
FORUM
SEARCH
WHO'S 
LOG 
RULES