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Old 09-19-2012, 02:49 PM
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AiboPet AiboPet is offline
"micro" and quirky
 
Join Date: May 2012
Location: I'm in San Diego, but lived in Hong Kong for a long time
Posts: 707
I don't REALLY have much to add to this....but I did Google "uratech TV" and got this ebay link so that maybe I could figure out just what one of these was.

http://www.ebay.com/itm/URATECH-DELU...-/260974380713

I actually happen to NOT have one of these or any of it's "sisters". This TV appears to be a rebranded reference design made by someone else. I recognize it as one I see called "Bentley" quite often. It might help you track down a schematic if nothing else.

My "general" tech bench experience with all the little chinese b/w sets I do have.....usually end up in finding cracks in the board (look for them around the area where the "round" flyback footprint is). If you suspect something looks like a crack in the trace....a simple "beep" check or however you like to check continuity with your meter on a point either side of the crack. Look for real suspicious electrolytic capacitors that are swelled on top....or sitting weird on the board like they may be swelled on bottom. Obviously look to see the back of the CRT and it's socket look okay. Usually if one of these is dropped, it won't usually break the cabinet except in extreme cases....but will usually break the PC board along an edge.....or right around the flyback (because it is relatively heavy during a fall and will stress the board as soon as the set hits the ground).

Otherwise....I'd really only look for cold solder joints, touch up ANYTHING that looks suspect. Touch up pretty much every "wire" soldered to the board like the yoke and CRT wires. I've seen ALOT of cases where the vertical will go away....and the yoke wires were cold solder points, etc.

As far as any real measuring.....I'd really only go as far as to trace 12V (likely) around from the power plug to the power supply regulator (usually a transistor looking item with a heat sink VERY close to the power plug). I'd check to see if anything at all was getting to the Horizontal Output Transistor (usually close to the flyback).

I HAVE gotten much deeper into these before just because I was bored....or STUBBORN, but usually I just don't get that far into these unless I can find schematics (REAL hard to find for these)

My money is on "it's broken and you WILL see it" if you are careful looking at the PC board. These just don't have bad parts like the "big boys" do...because they just aren't old enough to "wear out" until they are from the 70's or earlier. That being said though.....I HAVE been stumped by a few of these "simple" sets, and I usually then just write 'em off and KEEP the parts to fix others. This of course only really works if you are collecting ALOT of the "same set" (as I do with the little "Coby" sets).

Sorry for the long post.....but this generally describes what I see in like 90% of these SMALL sets.

Playing with these really little sets differ from the big roundies and consoles...BECAUSE they are portable, get dropped, see weather, a CAT can knock one off a table....and these also tend to be used in REALLY crappy situations like sitting in PILLOWS on a bed or whatever, get thrown in closets and stuff. They almost ALWAYS suffer more "physical" trouble than anything else.
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My current "holy grail" is trying to get enough parts together to get a Singer TV6U going. Been kicking my ass for nearly a year now :-P

Last edited by AiboPet; 09-19-2012 at 06:24 PM.
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