[Amps] State of the Amp

[Bill Turner]

ORIGINAL MESSAGE:

At 09:50 AM 8/22/2006, Peter Voelpel wrote:
>Tony is using factory data when comparing the 8877 with the GS-35b while
>using amateur data (>ICAS) with the GS-35b ;-)
>The 8877 does the same power as the GS-35b with less drive.


------------ REPLY FOLLOWS ------------

The 8877 has some advantages, to be sure:

1. Lower drive requirements by about 30% approximately.
2. Smaller size and less weight.

But it has disadvantages too:

1. Much higher cost. Approx $900 vs $110 USD. Buy eight for one!
2. Requires an expensive socket and chimney.
3. Lower maximum frequency for full ratings. 250 vs 1000 MHz.
4. Higher heater power. 50w vs 37.8w.
5. Higher input capacitance, approx twice in GG.
6. Higher output capacitance, approx twice in GG.

The GS-35b chimney can be a replacement glass for a Coleman lantern, 
less than $10 at any sporting good store in the US, and no mounting 
hardware required. Tack it in place with a few dabs of silicon RTV 
and it's easily removed when needed.

Obviously there are tradeoffs - no tube is perfect for all 
applications, but to me the advantages of a GS-35b for homebrewers 
are overwhelming.

Bill, W6WRT