Quasar Troubles - Videokarma.org TV - Video

maxm · #1 08-28-2004, 03:35 PM

I picked this set up at a resale store today, it is the same set that Chad Hauris has in the gallery:
http://www.audiokarma.org/gallery/sh...cat=503&page=1

The problem with my set is that the picture looks like the Service Switch is on, with no vertical deflection, and two or three colored lines in the center of the screen, I assume this has to do with a service switch, the picture is exactly the same on my Zenith set, with the serivce switch on.

The problem is that I can't find the serive switch on this set. Does it have one?

I looked all over the chassis, and couldn't find anything...

The 5 tubes (hybrid set) are good, and this is about as far as my skills go with these newer sets.

Quasar/Motorola Color Set:
Service Model Number WP467GWA
Chassis E16TS-929-F01
Tech Manual CTV-6

Thanks for any help...

#2 09-09-2004, 01:44 AM

Your problem is most likely due to failed electrolytics in the vertical section,defective vertical outputs,or vertical osc is not working.Start by checking for bad caps in the vertical then testing the output transistors/tubes.Don't run the set with the brightness turned up when the set has no vertical deflection.

Chad Hauris · #3 09-09-2004, 06:27 AM

I think this set uses a tube for the vertical output...I also don't think it has a service switch.
If you have a scope, put it on the grid of the vertical output tube.
(Use isolation transformer on the TV set...it is a hot chassis).
Check for a waveform...if present, the problem is somewhere in the output stage, if not, the oscillator is not running.
Check the vertical height, vertical hold, and linearity controls...there may be a burned spot on a control.
If these do not check out it would be a good idea to get the Photofacts folder.

maxm · #4 09-09-2004, 09:38 PM

Thanks for the help, I finally got a chance to look at the set tonight. I removed the deflection module to take a look at it. Could it be a bad connection at the module? I know some of the sets that used modules had a lot of problems with contacts. I will check out some of the caps on the board, I believe there are only two electrolytics on the board, I believe those tow orange things are since they are makres as C7 and C77, and have a + sign one them as well as a velue of 50/50 and 8/50, the value is first, the voltage is last right?
There are two regular plastic caps, and a bunch of "eurpoean" style caps from Germany, but these are all low value, not electrolytics. Are these reliable, or known for failing?
Adjusting the vertical controls have almost no affect on the picutre, though I was able to get it to expand to about an inch by finding a certain spot on the vertical lin. ro height control.
Thanks for all the help, and here's what the picture looks like now...

maxm · #5 09-09-2004, 09:42 PM

Here's the deflection board...

#6 09-09-2004, 11:13 PM

Try changing those two electrolytics,you should be able to get those at radio shack.Those other caps you mentioned are usually good however, I have seen a few bad ones so it would be a good idea to check them.As mentioned in a previos post, check the pots in the vertical section.Also try cleaning the pots.

#7 09-09-2004, 11:19 PM

Also what is that large black component by the tube on the left??? It looks like a molded paper cap.If it is a paper cap it could be causing the trouble if it is leaky

Chad Hauris · #8 09-10-2004, 09:07 AM

Also it would probably be a good idea to check voltages in the vertical area...I can give you data from the photofacts folder such as voltages tomorrow from our repair shop...sorry, we don't have a scanner so I can just give you text info but it should be of some help.

maxm · #9 09-10-2004, 07:23 PM

OK, I'll replace those two electrolytics and there are two of those molded paper caps around the vertical output tube I'll replace, and see how the set works...

Wish me luck...

Chad Hauris · #10 09-11-2004, 12:53 PM

OK...I've got the photofact folder, it's number 1207.
The feedback side of the vertical oscillator is the triode of the 6BL8 tube.
Pin 1 is plate, 90.0 v.
Pin 9 is grid, -28.0 v.
Pin 8 is cathode, no voltage given.

The power output side of the oscillator is the 6CW5.
Pin 7 is plate, marked do not measure because of HV pulses.
Pin 9 is screen, 240 v.
Pin 2 is grid, +23.0 v.
Pin 3 is cathode, 47 v.

andy · #11 09-14-2004, 07:43 PM

Here's a scan of the vertical section from Sams 1207. Let me know if you need more of the schematic, or higher resolution.

maxm · #12 09-14-2004, 10:15 PM

Thanks for the schematic and voltages, I'm working on replacing some caps on the module, will probably test it out tomorrow, and take some voltage readings...

maxm · #13 09-17-2004, 07:19 PM

After I replaced two of the questionable caps on the board (The other two I didn't have any replacements for), and cleaned the contacts of the module with DeOxit, and after fiddling with the controls for a while I was rewarded with a nice color picture...

The tuner needs to be cleaned, but after that I will have a nice set.

Thanks to you for all the help, another old American TV was saved!