Narrow picture when set first comes on

[Dan Starnes]

My Admiral set (model C2256 N) that I watch frequently did not produce a picture when I turned it on tonite. I had sound, but no pic whatsoever. After about 1 minute I did what my Dad used to do, I slapped it on the side. A faint pic was produced, then a narrow picture, from side to side came. The images were not distorted. As the set warmed the picture filled to the entire screen, and looked as good as ever. I pulled out my Sams and and in the tube failure check chart a narrow picture could be caused by 5 different tubes. They are
Horiz mult
Horiz output
Damper
HV Rect
LV Rect
Slapping it on the side makes me wonder also if I have a bad pin connection.
Might get a chance to look at it tomorrow. Doing some maintenence on my 1960 Pontiac this weekend and the ole back is sure sore. Laying across an engine bay and installing points in a distributor in the rear of the engine hurts a whole lot more at 50 years of age then I remember when I did it the last time at age 40. Lots of room in those old engine bays, but 6'4" of me still says it is too small. But man, when I drive her, I am king of the road
Dan

[Old1625]

I hear ya about car maintenance; I'm roughly the same age, and have recently dealt with a distributor at the back of the engine in my '68 Jeep Wagoneer.

Now, back to topic: If you turn the set on again and do not get a normal picture you need to shut 'er down immediately, and not operate it without some troubleshooting. If the culprit turns out to be due to insufficient horizontal drive the horizontal output tube could cook itself to death in short order.

Intermittant filament supply to one of the horizontal sweep tubes would be a possibility to explore first off....

[andy]

...

[Dan Starnes]

Thanks guys for the input. I will not use the set till I indeed do some troubleshooting. Also, I have been on ebay and have all but 1 of the tubes listed above bought. Time to do a good inside cleaning while I am at it.
Dan

[Dan Starnes]

Well that was easy. Got inside the back of the set and setout to just look at all the horizontal related tubes. First tube I touched was the Horizontal output tube. When I removed it and tried to remove the lead to the top of the tube the metal that the lead clips to fell off. Replaced that tube with a known good tube, gave set a good dusting inside and turned it on. Now works fine, also did a minor centering adjustment via the magnet on the yoke.
Again thankyou for your input, I am learning from this site, as well as the links you all lead me to.
Dan

[Dan Starnes]

Turned on the set tonite and narrow picture again. Shut set down and took back off to have look see while powered up. Low voltage Rect tube was bright bright bright and blazing hot in no time. Shut set off. Any ideas?
Dan

[bgadow]

It has been recapped, right? The filter caps would be my first guess. If it has new caps, my next thing to check would be some of the bigger resistors.

[avionic]

If its a narrow picture horizontally go for the Horz.Output and damper.If its a narrow picture vertically go for the Vert Osc./output.
60 poncho... Heres my 80 poncho
http://audiokarma.org/forums/showpos...75&postcount=1

[Dan Starnes]

Set was recapped 2 years ago. I am going to pull the chassis and look further as I did some tube swapping with no success.

Avionic- Great looking bird!!!
Dan

[avionic]

Hows the progress Dan ? BTW thanks..
Are the heater voltages OK?

[Dan Starnes]

I have discovered that the work done a couple years ago was not complete. I asked for a complete recap, but I see a couple that are obviously old or original. I am going to remove the chassis tomorrow and take it to Brashears TV repair in Hannibal MO on monday to get all the caps replaced as well a general state of health check.
Dan

[Dan Starnes]

Pulled the chassis today. I count 6 new caps in this. Quite a few bad caps left in it.