>PAUL HEWITT wrote:
>>Greetings Ian
>>I'm afraid the speed up circuit you
>>mention does not work very well for the
>>vacuum relays. It indeed does speed
>>things up but the circuit doesn't
>>release the relay fast enough for true
>>QSK. ...
... ...
>That brings me to one final warning about this whole speedup/QSK thing
>(and I'm sure both Rich and Paul will agree)...
>
>To make fast RF switching work, you *must* use the fastest possible PTT
>output from the transceiver! Don't ever use the relay option - it wastes
>valuable milliseconds that you can't afford.
** Yea, verily. A simpler solution is to replace the lethargic
relay-option with a 300v/0.5a NPN switch.
> Some transceiver PTT relays
>are so slow that the RF output has already started *before* the PTT
>signal reaches the amp (duh...)
>
>If the fast transistor-switched PTT output of your transceiver won't
>handle the voltage/current needs of your amp, then modify the amp with a
>fast transistor switch.
** amen
Rich, AG6K, 805-386-3734, www.vcnet.com/measures
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