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Sun Feb 27 13:35:59 CST 2005


much better info and also have writings, and RCA also put out 
training manuals for particular chassis.

JVC doesn't do much on this just an schematic, troubleshooting charts 
and raft of adjustment instructions in slim floppy books.  Same thing 
with Samsung, marginally better but their TV isn't my taste since it 
tinkered too much with circuit that it is hard to troubleshoot.  
Samsung liked to use philips ICs which is lousy and using AKB for 
CRTs.  we don't like those!  This kills the useful lifetime of sets 
because tube is still useable when AKB kept it shut and cannot be 
bypassed bec of under digital control via that jungle IC programmed 
by microcontroller based on contents of eeprom IC.
I had blank samsung tv that like this and it was not too old to 
cause akb to blank tube and found out later on another similar 
samsung while adjusting corrupted eeprom data the pix blanked out 
then popped back on when value reached within range.  Now I know why!

RCA shamefully started using AKB in ATC113 series.  :-P  I think it 
has schematic that might have a way to turn off AKB.

 > Then all (!) you need to do is find the video detector stage and 
feed in 
> your composite signal at the output of that stage. Hopefully the sync 
> separater takes it's feed after that point (it's almost certain you can 
> find a point where this is the case) so you really can feed in a 
> composite signal and expect it to work.

This is dandy in really ancient sets with older discrete IF stages.  
Sets in last 10 years have moved on to one jungle IC with SAW filter. 
In other decent sets, tuners pipe the IF right to the Y/C circuit 
(either analog or digital comb) and feed Y/C to the jungle via 
switches if set have inputs (Y/C is same thing as s-video). 
Component video (three jacks) is fed directly to jungle itself.  Just 
this year few brands makers finally released sets (my thought) super 
jungle.  I call this "super jungle" it has microcontroller & jungle 
in one DIP package.  Actually made my day much easier to repair 
those, less complex. But i know this isn't great for others who like 
to hack but those always have composite inputs (those yellow RCA 
jacks) so this is less of a problem IHMO and especially JVC with 
pincushion makes great HUGE composite monitors with those vivid, 
sharp CRTs (many used RCA CRTs !!)  (25", 27" without those swelling 
problem.

I really loathe Philips with that all in one SIMM module.  It has 
jungle, microcontroller, audio processing & input switches in few 
tiny SMD ICs all unprobeable bec it's so damned tiny and stuffed 
into worst place without getting bitten or no room for probes.  And 
it's 100 bux part and is bit high failure rate.  The mainboard is 
only way u can probe around.  Their philips schematics is locked and 
unviewable and must pay big bucks to own key for each CD to view 
only on ONE PC, installing same cd on diff PC gives different key #.  
RCA and others isn't like this.

Cheers,

Wizard

> 
> -tony



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