Tubes...

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Jonathan KC8RYW
Posts: 1747
Joined: Fri Dec 28, 2001 4:00 pm

Tubes...

Post by Jonathan KC8RYW »

Does anyone remember these?

I have an Amperex 5894B/8737 dual-triode, and an RCA 8032 tube I pulled out of my VHF MoTrac.

How do I tell if these are "good" or not?

The lady at the drug store on the corner gave me a funny look when I asked where the tube tester was. :lol: Just kidding.

Thank you.
73 DE KC8RYW
Random Motorola Part Number:
SYN1894B - V3m Sprint-branded Battery Cover
Jim202
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Joined: Sun Sep 09, 2001 4:00 pm

Re: Tubes...

Post by Jim202 »

Now Johnathan, you have been around here long enough to know the answer to your own question.

It would be easier if you just put the tubes back in the radio and fire it up.

Jim
Jonathan KC8RYW
Posts: 1747
Joined: Fri Dec 28, 2001 4:00 pm

Re: Tubes...

Post by Jonathan KC8RYW »

Jim202 wrote:Now Johnathan, you have been around here long enough to know the answer to your own question.

It would be easier if you just put the tubes back in the radio and fire it up.

Jim
Ah, true.. but the radio was broken, as a large part of the exciter section was smashed [I guess someone beat me to it, just kidding.]
Otherwise, I would have fired it up, and stood by with the fire extingusher.
73 DE KC8RYW
Random Motorola Part Number:
SYN1894B - V3m Sprint-branded Battery Cover
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Robert HT220
Posts: 664
Joined: Wed Sep 04, 2002 12:59 pm
What radios do you own?: JT1K VHF, MT1K VHF/UHF/800C

Post by Robert HT220 »

I have a tube tester for octal and loctal tubes, normally used for testing the old FM/AM radio tubes and ones out of old TV's. It's pretty cool, works fine, and the test light built in still works. After 50 years! :D

Robert
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wa2zdy
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Joined: Mon Jul 01, 2002 9:13 am

Post by wa2zdy »

Corner drug store type tube testers only test for cathode emission. Now granted, if the cathode emission is down, the tube won't work so well. But they don't test the tubes under load. Testers that put a load on a tube were called mu testers (the u is really a Greek letter, but I don't want to bother seeing if I have it here . . . ). They worked "better," weeding out tubes that got past the drug store.

For transmitting tubes, there's just no reliable way to test without putting them in a transmitter. Sorry to say, that's the reality. It's sort of like a mechanic starting the car, hearing the engine idle, and pronouncing all to be well. Put that sucker in gear, let the clutch out and see how things change.

Tubes, I remember them well. A drawer full of tubes in the trunk . . . been there, done that, worked ok too. PRE-Motrac!
Chris,
Hamming 31 years
http://www.wa2zdy.com
Wesley Chapel, Pasco County, Florida
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richyradio
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Post by richyradio »

If the glass is broken, they are no good.... :)
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