Pal 321 base tube amplifier help.

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Tinkerjim
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Pal 321 base tube amplifier help.

#409348

Post by Tinkerjim »

Hello i have a pal 321 tube amplifier base.
It has 1 6lf6 driving 3 6lf6.
It lights up
All tubes light up good
Fan runs good as well.


But it does not transmit.
Radio won't even transmit through it.
So far i have changed both big filter capacitors as well as the recifier diodes.
Some one said it could be relays.
Had problems finding right ones.
So i ordered a relay kit offline. I build the kit as instructions said.
But I'm having trouble getting it wired to the amplifier.
Any help would be appreciated.
Thanks Tinkerjim.


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443 Arizona
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#409352

Post by 443 Arizona »

first, pull the tubes and store them safely while messing with the amp.
it does appear that it may be a relay problem, but i dont think your relay kit is the answer.
your input should be present , so focus on the output,,,
tubes can light up but still be bad,,,, also, give it 10 or 20 minutes of on time to fry in any loose electrons, your just going to have to trouble shoot it all really,
some special equipment would be extremely helpful,, at that point, take it to a radio shop.







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MDYoungblood
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#409367

Post by MDYoungblood »

You would be surprised at how many of those older tube amps have been hooked up backwards and fired the relay circuit. If the relay is closed when “off” the radio should transmit through the relay to the antenna jack. If the relay is clicking when it senses wattage try switching tubes around, if one is bad it would most likely be the driver tube.
Wish I could be more help.

3’s

Greg






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Tinkerjim
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#409369

Post by Tinkerjim »

Thanks for the response.
The relay was not clicking.
No power getting through.
Not even the radio transmit. Nothing.
The original relay board had 2 relays
2 pins on bottom. 6 pins on top.
I'm trying to install a relay kit i bought online. This relay board has only 1 large relay.. Any ideas on what I'm doing wrong would be appreciated.. Thanks Jimmy..







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warlock35po
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#409387

Post by warlock35po »

Hello. I have seen many 20LF6 sweep tubes light up really good and still test next to nothing on a Mutual Conductance tester.Hope that is not the problem .At a guess I would say a new old stock 20LF6 could easily be better than a 100 bucks each,plus insured shipping, good luck.Regards, warlock35po







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