What am i doing wrong?

[jr_tech]

Originally Posted by jbivy

How do i check the B+ ?

Do you have a schematic?
I would use a multimeter attached to the power supply output with alligator clips (so you don't have to hold them in place) positioned so that you can see the meter while the tv is operating... watch for changes in the B+ voltage as the set goes into failure mode.
If the set uses a 5U4 or similar rectifier tube to generate the B+ voltages, try to watch it as well. What is the model# of the set... perhaps I can look it up and point out specific points to monitor.
jr

[old_coot88]

Often some judicious prodding and tapping with an insulated tool will localize an intermittent.

[wa2ise]

Bad resistor that overheats? After you get a digital volt ohm meter, measure all the resistors. Be aware that in some cases, you will also measure what else is parallel with the resistor, but that will make for a lower reading. A too high reading will mean a bad resistor.

[jbivy]

Originally Posted by jr_tech

Do you have a schematic?
What is the model# of the set... perhaps I can look it up and point out specific points to monitor.
jr

I havent found a sams for this yet, they dont seem to be around for packard bells. The back of this says model 24s and the inside on the chassis it says "chassis style tube layout 8851".

Ive a rather nice multimeter, just perhaps not the know how to use it.

Im a radio restorer and well, tv's are still pure magic to me at this point. Im just used to replacing everything and having them work.

[jr_tech]

Originally Posted by jbivy

I havent found a sams for this yet, they dont seem to be around for packard bells. The back of this says model 24s and the inside on the chassis it says "chassis style tube layout 8851".

Packard Bell is listed under a later name... Teledyne.
Here is the Sams photofact index for "T", but I don't see a 24s, only numbers like 24ST1, 24ST2... and numbers like that. Looks like these are sets from 1956,1957 which might be about right. Perhaps you are missing part of the number, somehow?

http://www.theschematicman.com/photofact-t.htm

jr

[marty59]

Even though you don't have a schematic a tube manual can sure come in handy. You would be able to know where to make measurments from and trace out some of the wiring/components and get more of an idea of what you are looking at.

[leadlike]

Could you tell us the model# of your meter? Then we'll tell you how to set it up for the checks you need to run.

You could even have a bad power cord-my test ocillator was dead, and after poking around it for hours, trying to find out why it died right after powerup-yup, the powercord was heating up, going high resistance, and killing the oscillator.

[old_coot88]

Originally Posted by leadlike

You could even have a bad power cord-my test ocillator was dead, and after poking around it for hours, trying to find out why it died right after powerup-yup, the powercord was heating up, going high resistance, and killing the oscillator.

I had a bizarre case in the shop one time, a series-string B&W TV that was turning itself on and off, not abruptly like with the switch, but fading in and out. The heater string was doing it. Finally traced it to the CRT heater which was "blinkering" by thermal expansion/contraction just like an auto turn signal blinker. Never seen a case of that before or since.

[compucat]

Originally Posted by old_coot88

I had a bizarre case in the shop one time, a series-string B&W TV that was turning itself on and off, not abruptly like with the switch, but fading in and out. The heater string was doing it. Finally traced it to the CRT heater which was "blinkering" by thermal expansion/contraction just like an auto turn signal blinker. Never seen a case of that before or since.

I had that happen in my Sparton AA5 radio. After a while of normal function, the set would go dead. If I left it alone, eventually it would come back on its own. One of the tubes developed an intermittent heater.

[AUdubon5425]

Originally Posted by jbivy

I havent found a sams for this yet, they dont seem to be around for packard bells. The back of this says model 24s and the inside on the chassis it says "chassis style tube layout 8851".

Sams 312-9 covers Packard Bell 24ST1 (chassis 88S1). I'll look to see if I have that one this evening.