[RTTY] Mono band amps

[Joe Subich, W4TV]

> From: Bill Turner
>
> The Russian GS-35b is so inexpensive these days it seems to make
> sense to me. One power supply could run them all (for single ops
> where only one TX is allowed at one time) and just switch to the one
> you need. Fan noise might be an issue if all five were left running,
> so a pair of 3-500s or some other instant-on tube could be used
> instead. That expensive bandswitch would be eliminated, although you
> would need to switch the input and output coax, easily done with
> inexpensive relays.

The tube is rated for 2 KW anode dissipation with water cooling ...
perhaps a water cooling system would significantly reduce the
blower noise <G>.

All the switching and filtering might be an issue with SO2R but
one could build high quality bandpass filters into the input
(before the TR relay so they were in circuit during receive) and
use a double Pi or double Pi-L output for improved harmonic
suppression in transmit.

Ten amplifiers could be switched between two radios with a pair
of 2x10 switches like the microHAM DOUBLE TEN Switch or the
"contest bands" could be covered with six amplifiers and a pair
of any of the 2x6 switches.  I suspect the cost of automatic
switching would probably eat up the cost advantage of mono band
amplifiers vs. a pair of auto-tune amps.

73,

    ... Joe, W4TV