Admiral Roundie Something explodes - Page 6 - Videokarma.org TV - Video

tvcollector · #76 02-05-2011, 01:42 PM

I guess i won't be shipping to them i guess..

UPDATE: I tested with hooking to the leads with the cap off, and same thing, The filament of the picture tube does not light up, nor does the Sencore make the noise like it's giving the tube juice.. So i guess Dead Tube..

Kevin Kuehn · #77 02-05-2011, 02:00 PM

That's weird that it was lighting up somewhat earlier. Have you tested another tube on the Sencore recently, to confirm that it's still working correctly? Have you taken a resistance reading across the filament pins?

Kevin

tvcollector · #78 02-05-2011, 04:52 PM

I tested another tube with the Sencore, and it worked with that one.. I have no other test equipment.. My guess is that the filament inside the tube was week and would have probably blown once the chassis was recapped and powered up the tube.. I looked inside the tube neck and i don't see anywhere that anything shorted out

DaveWM · #79 02-05-2011, 04:54 PM

and did you test the filament wires for continuity?

tvcollector · #80 02-05-2011, 04:58 PM

How would i do that?

tvcollector · #81 02-05-2011, 05:05 PM

I think i see what you are saying, the leads continue into the glass and looks like they are not broken anywhere

DaveWM · #82 02-05-2011, 05:07 PM

electrical continuity, a complete circuit, a multimeter set in the ohm will do fine, the heater should be a few ohms, if not then it is a open circuit, burned out, will not work.

tvcollector · #83 02-05-2011, 05:16 PM

I don't have a multimeter.. All i can do to check the continuity is look as far as i can in the tube to see any shorts, but i can only look so far, but if the Sencore is not lighting the filaments, and not giving juice to the tube i would assume there are problems.. It did fail both cutoff and emissions and the HK shorts, when the filaments where lit up. it's probably burnt out.. Im looking for another Tube while i still have the extra $ to spend, and so far im not having any luck..

Kevin Kuehn · #84 02-05-2011, 05:57 PM

These old round CRT's don't generally fall out of the sky. You'll need to be patient, and then be in the right place at the right time. They're out there, but not usually right now, and real cheap. CRT's were never stock piled by repair shops like the common little tubes in our TV's. JMO

Kevin

tvcollector · #85 02-05-2011, 07:05 PM

Problem is is that i have the extra $ now, i may not have it when one pops up, you know how things usually work, something pops up, bills etc wanting to take our money.. Plus if i don't get this project going and fixed, my interest will probably become lost, and it will just sit back in a corner somewhere..

jeyurkon · #86 02-06-2011, 12:10 AM

Quote:

Originally Posted by DaveWM

pretty sure it uses a switching power supply for the filament, that is what you are hearing, mine does it to, its pretty hi pitch, I would guess in the 10-12khz range.

If it's 12kHZ I might have trouble hearing it. I suppose it would also vary in loudness quite a bit depending on the specific components, also background noise. I'll pay closer attention the next time I use it.

leadlike · #87 02-06-2011, 01:31 AM

You can get a multimeter with continuity test for as little as $3 at Harbor Freight. Their ultra deluxe meter costs about twenty, and does just about everything you would ever need a meter to do to fix your television.

You can also build a continuity tester with something like a couple of C batteries, and a radio pilot lamp, like a #44-the bulb should light if the filament is intact. We only keep yammering on with this filament thing as it is very, very rare for a crt filament to blow-usually everything else in the picture tube goes bad before the filament fails.

tvcollector · #88 02-06-2011, 04:08 AM

Quote:

You can also build a continuity tester with something like a couple of C batteries, and a radio pilot lamp, like a #44-the bulb should light if the filament is intact. We only keep yammering on with this filament thing as it is very, very rare for a crt filament to blow-usually everything else in the picture tube goes bad before the filament fails.

Than why is the Sencore not powering the filament? I think when the Sencore does Tube tests it powers up the filament, it has done that on every set i've tested.. It's not the Sencore, because i went and tested another set i have to make sure..

compu_85 · #89 02-06-2011, 09:43 AM

That doesn't change the fact you need a meter when working on one of these sets. You'll find many uses for it beyond TVs.

miniman82 · #90 02-06-2011, 09:45 AM

Right, a decent meter should be the first tool you buy! Don't forget a set of probes too, mine have pointy tips and aligator clips that are interchangable.