Amplifone Hv woes

Deadly

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This has to be the crappiest board I've had to work on.
WARNING - REPAIR NIGTMARE DEAD AHEAD!
Someone soldered 10 resistors in backwards (2 of which were the incorrect values) , used an NTE379 instead of a BU406D, 7924 was blown in half, 7824 was blown, both 1N4001's were cooked as well as both 5w 50ohm resistors and lastly a ground wire was loose. This has the original red flyback so before I order a new one I thought I'd post here.

So now knowing what I have replaced/fixed I have hit a brick wall and need help. I have no picture, no LED lit on the HV and the BU406D gets screaming ass hot. VR1 registers +30 and +11.00 while VR2 is spot on for -30 and -24. Deflection board works perfectly with other HV board I have.

Any help/suggestions greatly appreciated.
 
How on earth can resistors be soldered backwards ???????

First: desolder the BU406D. It's perfectly safe to run the board without it and enables you to troubleshoot the first sections without problems.

See if the HV generation circuit produces a block-wave.

I do assume you've read the Amplifone FAQ ?
 
LOL!!! Sorry guys it was late when I posted. I meant DIODE you bastards!

@Level42 - I don't have a scope. Checking wave form NOT an option.

I would tend to be with Tester007 to replace the flyback but before I did I figured I'd try to revive it hoping the flyback was good. About all I can think of is to replace the 555 and if that doesn't work then flyback is next. Unless of course someone else comes in with a different idea ;)
 
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LOL!!! Sorry guys it was late when I posted. I meant DIODE you bastards!

@Level42 - I don't have a scope. Checking wave form NOT an option.

I would tend to be with Tester007 to replace the flyback but before I did I figured I'd try to revive it hoping the flyback was good. About all I can think of is to replace the 555 and if that doesn't work then flyback is next. Unless of course someone else comes in with a different idea ;)

You have about as much chance on having a good red as winning the lottery ;)

I'm with Tester....

Get a Cinelabs HVT...
 
The gold band on resistors runs north and south, and must be on the west side, unless mounting on the solder side then east is ok.
 
The gold band on resistors runs north and south, and must be on the west side, unless mounting on the solder side then east is ok.

:D :D :D

Seriously, we were taught at electronics education to solder them all in the same orientation so that the color band would be easier to read. Not a bad idea, but who reads those bands ? I measure all the time.... :D
 
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