[600MRG] A 630 meter transmitter

[Kenneth G. Gordon]

On 28 Jan 2018 at 19:55, Steve WD8DAS via 600MRG wrote:

> 
> Eric wrote:
>     If going to parallel 807s (or 1625s), a 6AG7 oscillator (xtal or ECO)
>     probably won't have enough output to fully excite the pair.
> 
> I think it can, if operating on the fundamental.

Of course it can: parallel 807s require 0.6 watts drive for 120 watts output, and a 6AG7 
outputs way more than that when operating at the fundamental..

Here is a transmitter using a single 807, driven by a 12BY7 (which is very much like a 9-pin 
6AG7).

http://www.w7ekb.com/glowbugs/projects/inexpensive75wattxmitter.pdf

There is even enough drive (barely) at 10 meters with this setup when the 12BY7 is 
quadruppling in one stage.

Or how about this one, operating at less than 1/2 the full plate voltage for the 807/6BG6s?

http://www.w7ekb.com/glowbugs/projects/65W%20at%20Low%20Cost.pdf

Ken W7EKB

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