PTK195 RCA

[ac611\remove\]

I was given this 46" RCA and found the main fuse was blown. Replaced the
fuse and the picture is the correct width but the bottom is bowed
upwards and the top bowed down. The convergence is also way off. I've
never worked on one of these before. Is there something common? Any
schmatics of these online? Thanks for any help.

Len

 

[[email protected]]

Len: Go to this discussion on Sci.electronics.repair re your problem.

http://groups.google.com/group/sci....+top+pincushion&rnum=1&hl=en#691677def7a68368

Also, I have the service data on this Chassis if you need something
from it.

Robert McPherson
Louisville, KY

 

[Jason D.]

Len: Go to this discussion on Sci.electronics.repair re your problem.

http://groups.google.com/group/sci....+top+pincushion&rnum=1&hl=en#691677def7a68368

Also, I have the service data on this Chassis if you need something
from it.

Robert McPherson
Louisville, KY

Don't worry about the chassis, don't adjust! The reason for fuse blown
was is the convergence power supply that is blown. It is small board
mounted on the black plastic panel. Held down by 1/4" hex bolts. Get
that convergence power supply fixed. There are two types of this by
the way. One use big black IC on Z shaped heatsink, other one is
small U shaped heatsink. Both have different appoaches to repairing
those two types.

Cheers, Wizard

 

[ac611\remove\]

Don't worry about the chassis, don't adjust! The reason for fuse blown
was is the convergence power supply that is blown. It is small board
mounted on the black plastic panel. Held down by 1/4" hex bolts. Get
that convergence power supply fixed. There are two types of this by
the way. One use big black IC on Z shaped heatsink, other one is
small U shaped heatsink. Both have different appoaches to repairing
those two types.

Cheers, Wizard

Hello again,

I finally got a chance to work on this thing! The convergence power
supply is not running (as Wizard said), it's the one with the
STK730-130. I don't have the full schematic but I do have a photocopy of
a diagram of the power supply from a training manual. Is it safe to try
to run this with no load to make sure there is no heavy current draw
from the convergence board, which I understand will shut down the suppy?
I haven't found anything bad with my meter and I suspect the STK is not
firing up.
Thanks for the help,
Len

 

[Jason D.]

Hello again,

I finally got a chance to work on this thing! The convergence power
supply is not running (as Wizard said), it's the one with the
STK730-130. I don't have the full schematic but I do have a photocopy of
a diagram of the power supply from a training manual. Is it safe to try
to run this with no load to make sure there is no heavy current draw
from the convergence board, which I understand will shut down the suppy?
I haven't found anything bad with my meter and I suspect the STK is not
firing up.
Thanks for the help,
Len

You're welcome, Len.

Ok, replace the STK730-130 IC. Any STK730-040 and up will sub in.

And check the diodes on output side just in case, check small
resistors on hot side.

Cheers, Wizard