Not that Ive ever noticed. I have some used ones with late 60's date codes
that are fine. I also picked up a distributed amp with 13 NOS 1983 date
codes recently. They were all fine after a 5 minute warm up when I then used
the original National test jig to match them. Got nice prices on Ebay.
The Eimac 8122W often has a much higher bias requirement than the RCA and is
out of range of the bias pot. Its a simple matter to move the range from the
stock -25 to -45V up to -35 to -55V. The Eimac has a bias range about half
that of the RCA so they still require matching.
----- Original Message -----
From: "Pat Barthelow" <firstname.lastname@example.org>
Sent: Tuesday, August 14, 2007 12:42 PM
Subject: Re: [Amps] Project for 8122 tubes
> Are 8122 Tubes that have been in storage for possibly Decades without use,
> likely to have internal gas problems?
> Sincerely, Pat Barthelow email@example.com
> Jamesburg Earth Station Moon Bounce Team
>>From: "sulai je" <firstname.lastname@example.org>
>>Subject: [Amps] Project for 8122 tubes
>>Date: Tue, 14 Aug 2007 13:03:08 +0300
>>I had some RCA 8122 tubes in my junk box since long time. Thinking to use
>>them in a homebrew project so I start to search for an amplifier project!
>>Either to UHF or VHF . HF Googling the net yields a zero project for those
>>if any on can help with schematic and more info I will be appreciated in
>>73s de 7z1sj Sulaiman
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