Telco KT-1403-v Triple Image problem [Calling Ken !] [FIXED]

[Arm123]

I have a Telco KT-1403-v chassis that i recapped and fixed a vertical deflection problem via Kens repair guide.

Upon testing after i capped and replaced the TDA vd-ic i get a triple image.  Im not sure what went wrong here.

The only thing i can think of is bad capping job ?  I noticed that there are 2 different versions of these chassis that have different cap values.

How can i tell if this is an early or later model chassis ?

Note: This chassis only has 1 v-hold pot, not 2 like others i have seen.

[Ken Layton]

The 1403V is VGA resolution not standard res.

My guide lists the differences between early and later production runs.

[Arm123]

Hey there Ken,  i realize that its a VGA monitor.  I am using this on a Merit XL Platinum machine, which is VGA.

I am still getting the triple image.  Now that you mention it, it doese look something like displaying a medium res game board on a CGA monitor.  Im Hoping its something stupid...

[Arm123]

Hey ther Ken...

"VR201 Mode Select 10 k ohm (may be 5 k ohm on some chassis or may be not present at all)"

Perhaps this is the problem.

[Arm123]

played around with hat pot and nothing special...

not sure where to go from here...  still displaying triple image, side by side.  If the TDA vic was bad, i dont think it could cause this ?

i have another telco chassis here thats dead... i guess ill attempt to revive that.

[grantspain]

have you tried a different 31khz video source yet?

[Arm123]

Hey there Grant,

This is a known good megatouch setup... However, i guess i should try another source.  Ill plug in my netbook.

[Arm123]

Plugged in my net book and i looks to have the same issue... but worse. Definetly a syncing issue.

[Ken Layton]

Don't know what else to tell you. Correct caps installed in correct polarity?

[Arm123]

Honestly, i have a couple caps around the TDA vic that im not sure about, cuz i dont know if this is a later or early model chassis.  The foil says on way, but the parts side says another (ill check to see what cap it is).

I do know that this chassis is missing q103 or q301...  cant remember which... not at the office, ill confirm.

I know im a pain in the ass... but i love you guys, just thought id add that 

[Arm123]

Iv changed out the vi and socketed and changed the LM IC on the neck... same crap.

Im looking over the diagram and gonna confirm the questionable cap polarities.

What does the 'mode select' VR do ?  I turn it and it does nothing.  Possible that IC202 is screwed up ?

[Arm123]

confirmed all the caps are in with the right polarity...

Its q103 and c412 thats absent from this chassis... looks like they were never present

[Arm123]

q102 is also missing...  wt heck ?

[Arm123]

been looking at the components on this chassis to determin if its a late or early model....

All the components jive with kens guide as an eraly model chassis... However, r313 puzzles me.  It says that it should ether be 47h but i can see there is a 33h installed... I check another telco chassis i have and its 33h too... strange

[Arm123]

just to confirm...  c419 positive should be going to gnd ?

[Arm123]

I have 2 early model chassis that are having sort of the same issues... it seems to be sync issues.

I also have a later model chassis that works perfectly with the same setup, so i know it got to be somthing wrong with these early model chassis.

Gonna keep playing with them and post my progress.

[Arm123]

quick update on this...

The triple image chassis ended up being the Hrz syc pots.  Someone swapped the two values.  H1 had a 10k and H2 had a 50k installed.  I swapped / switched them and it worked.

Also, on these early model chassis, i noticed that c307 is marked incorrectly on the parts side of the board.  The sikscreen side is correct.

Also noticed that r313 is 33ohm not 47 like it should be.  I have 2 of these chassis that came this way.  Looks like its from the factory.

I now have 2 early model chassis and 1 late model working.  Just one problem with one the early model chassis.

The image appears to be moved too far to the right and cut off.  The end of the cut off image appears to come out on the other side / left side.

I have tried adjusting it out, but i cant get it right.  The H sync is VERY touchy and comes out of sync easily.  I have recapped this thing too.  Just looking for any ideas.

[Arm123]

image is a bit 'wobbly' too...  pin cushun control doest do much.  Already replaced C421 (1 uf @ 50 volts), C422 (1 uf @ 50 volts), C313 (100 uf @ 50 volts), and C314 (100 uf @ 50 volts)