No-name PSU repair (ChangHong TV)
Good day folks. You know how we've got a thread about the worst/strangest power supplies ? Well this TV inspired me to propose we make one for the worst TVs as well 
I've just fixed a ChangHong TV (yeah, this exists ) which had power supply issues and while the PSU is definitely not as bad as some others I've seen in terms of design, it's still a strange specimen, so I decided to share my findings with you.
Now the repair itself is nothing to write home about: the PSU went "click-click-click" and it was just a busted cap (C5 in the picture) on the VCC supply for the switching IC, which is a little SMD IC on the bottom (didn't picture that sadly). Just out of curiosity, I looked up the model number of the PSU and much to my surprise not even Google's heard of this thing before...seriously, searching for AYL220405 didn't return a single result, not even an auction site where someone may be selling one of these - NOTHING So I'm....proud ?....for lack of a better word, that if someone runs a search on google for this thing now, they'll probably run into this post I must admit I'm disappointed I didn't get a chance to grab some pics of the bottom just in case someone will ever need a value of a SMD resistor that's gone boom....sorry, my bad 
So if something were to go horribly wrong on this PSU and you had some fried resistors and SMD capacitors that you had no way of knowing the values of, you're kinda screwed unless you're a real pro and know the circuit topology and know exactly what values the components should have based only on how they're connected. Fortunately it wasn't the case here - just a simple dry cap, although I DID fix one of these "Changs" before which was a lot worse: fried traces, blown SMD resistors and caps....it was a mess. After a lot of scrubbing, tinkering and rebuilding traces I was able to get that one to fire up also. Make sure you're using the series light bulb when doing this ! I had mine at full brightness a couple of times when messing around, so something would've blown for sure.
So there you have it, a completely useless piece of information that nobody asked for but I thought I'd share anyway Cheers.
I've just fixed a ChangHong TV (yeah, this exists ) which had power supply issues and while the PSU is definitely not as bad as some others I've seen in terms of design, it's still a strange specimen, so I decided to share my findings with you.Now the repair itself is nothing to write home about: the PSU went "click-click-click" and it was just a busted cap (C5 in the picture) on the VCC supply for the switching IC, which is a little SMD IC on the bottom (didn't picture that sadly). Just out of curiosity, I looked up the model number of the PSU and much to my surprise not even Google's heard of this thing before...seriously, searching for AYL220405 didn't return a single result, not even an auction site where someone may be selling one of these - NOTHING
So I'm....proud ?....for lack of a better word, that if someone runs a search on google for this thing now, they'll probably run into this post I must admit I'm disappointed I didn't get a chance to grab some pics of the bottom just in case someone will ever need a value of a SMD resistor that's gone boom....sorry, my bad So if something were to go horribly wrong on this PSU and you had some fried resistors and SMD capacitors that you had no way of knowing the values of, you're kinda screwed unless you're a real pro and know the circuit topology and know exactly what values the components should have based only on how they're connected. Fortunately it wasn't the case here - just a simple dry cap, although I DID fix one of these "Changs" before which was a lot worse: fried traces, blown SMD resistors and caps....it was a mess. After a lot of scrubbing, tinkering and rebuilding traces I was able to get that one to fire up also. Make sure you're using the series light bulb when doing this ! I had mine at full brightness a couple of times when messing around, so something would've blown for sure.
So there you have it, a completely useless piece of information that nobody asked for but I thought I'd share anyway
Cheers.
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