The 813 is almost a 70 year old design yet it is still one of the best tubes
ever made.
Brand new US military surplus ones are on Ebay on a regular basis and at
very low prices. No matching is required. I recently bought 4 813's and
sockets off Ebay for around $80 for all. These are for an AM amplifier.
In GG service the 813 IMD is in the -33dB range according to published info
making it a very clean performer.
My regular SSB/CW HF amp uses 3-500Z's and they are also an excellent tube.
Carl
KM1H
----- Original Message -----
From: "Mike Bondarev" <mikebond@mosfirm.ru>
To: <Amps@contesting.com>
Sent: Monday, December 31, 2007 2:42 AM
Subject: [Amps] 2x813 or 2x3-500zg ?
> Hello to everybody! Happy New Year 2008!
> In the coming year I would like to build an amplifier for "everyday
> use". For the contesting I already made the amplifier with GU-84B and
> GM3SEK's tetrode boards and it work fantastic! The second amp I would
> like to make with glass tubes. What you guys can recommend me? I was
> thinking about two 813 in grounded grid configurations but now I'm
> thinking why not the pair of 3-500zg from RF-parts? I newer used 3-500zg
> before so I can't compare it to 813. I understand the difference in
> pricing but I also know it's easy to buy matched set of 3-500zg but
> it's just impossible to find matched pair of 813.
>
> Regards, Mike RL3BM
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|