Early 80's RCA Projection TV Model: PGR100WR

[kevin nexes]

The subject has a collasping raster. Used to be intermittant, but now
is stuck in that all of the video is in about 2/3 of screen height.
The bottom 1/3 of the raster can be seen but is 'folded over' and
compressed into about an inch on screen. All three colors have the
problem.

Makes for watching the credits roll at the end of a movie alot of fun
because the words literally reverse direction at the fold over.

The video in the vertical blanking interval can also be seen at the
top of the raster. I bringn this up in that I may also have a picture
size problem. This video is in the interesting form of black and white
pulses, presumably "in channel data" from the cable company.


The subject has served me well, and even though purchased in '83, the
unit still has great performance otherwise and remains an integral
part of my home theather. I'd be willing to invest all my time needed
to bring it back to spec, and prefer to take a shot at fixing it
myself but looking for someone here to shorten the diagnosis.

I'm a electronics engineer and have access to scopes, ESR's, test
pattern genertors and such and I *DO* have the microfiche version of
the service manual and have no aversion to diving right in.

Thanks for your advice in advance
Kevin

 

[john]

Ok ! ESR all the caps in the Deflection and scan circuits
whilst in there check for dry solder joints.

Good Luck

kip

PS There is a standup ceramic type IC close to IHVT check it also
and change that 1000mfd very close to IHVT.

 

[John Del]

Subject: Early 80's RCA Projection TV Model: PGR100WR

From: [email protected] (kevin nexes)
Date: 9/23/03 5:28 PM Eastern Daylight Time
Message-id: <[email protected]>

The subject has a collasping raster. Used to be intermittant, but now
is stuck in that all of the video is in about 2/3 of screen height.

These use a couple of ceramic hybrid ICs, long discontinued. The one with the
vertical on it can be resoldered, but it's extremely difficult to do it where
it will last a long time.You can locate the part number on your fiche, and see
if anyone has one from a scrapper.

John Del
Wolcott, CT

"Nothing is so opportune for tyrants as a people tired of its liberty."
Alan Keyes

(remove S for email reply)

 

[Bill Jr]

Actually the vertical hybrid module at location M701, generic number HM7052,
Hitachi part number 2370542 is still available and in stock at
www.tritronicsinc.com

At $89.36 it would be best to verify that your set actually uses this part
before ordering.

It would also be prudent to do as another post suggested and replace most
(if not all) the caps in and around the sweep/deflection circuits as well as
the power supply regulation area.

Good Luck,
Bill Jr