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#1
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Tube question from a rookie
Im testing a tube 5AQ5. Datasheet shows 3 and 4 are the filament and multimeter checks them as having continunity. It also has continunity on 1 and 7 which it shows as grid 1 for both. Is that okay?
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#2
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Yes, that is correct
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#3
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Shoot, thought I found the problem. Now to start checking capacitors
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#4
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Quote:
You have to determine where the original fault really lies. |
#5
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I had someone else say B+ also (not sure what that is). There is a rectangular resistor near the rectifiers that I suspect is bad. Multimeter and resistance test don't give consistent results and there is corrosion on it's lead that seems to be coming from the resistor itself and no other components have any corrosion/oxidation at all. Waiting on a new one to confirm my theory.
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Audiokarma |
#6
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Quote:
The origin of the term dates from the first tube radios in the 1910's and 1920's...Until the late 20's there was no practical way to filter rectified AC to be clean enough to NOT swamp out RF/audio with AC powerline hum in radios, thus all radios ran on batteries...Back then the "A" battery ran the tube heaters/filaments, and "B" ran the plates...There was sometimes also "C" for the grid bias, but modern resistor dividers from the B supply eliminated the need for "C".
__________________
Tom C. Zenith: The quality stays in EVEN after the name falls off! What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4 |
#7
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You'd have to check the voltage on both sides of the resistor, meter set on AC range. |
#8
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That was indeed the, or at least one of the problems. No to figure out why half the screen doesn't work. Oh fun with vertical
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#9
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In your next post, include the chassis number and maybe someone has the schematic for it. You need one to have it when doing a restoration. |
#10
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Its a Z1819JZ chassis is a 15z31 and I have one for it. Only way I was able to find out what resistor I needed as the bad one was so worn there where no numbers on it.
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Audiokarma |
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