For what it's worth, here's the method I use to ensure proper CW QSK
sequencing and to avoid hot-switching. Although all but one of my amps is
protected from hot-switching, it's still good, cheap insurance and has
worked flawlessly for me.
I created a second open-collector switched transistor output on my external
keyer. The open collector is then run in parallel with the transceiver's
amp switching line. In essence, the added keyer line ensures proper closure
on the leading edge, then the rig's T/R sequencing takes it from there to
ensure that the amp line is released after the trailing waveform edge. This
"bussed" arrangement combines four transceiver's key lines with four
amplifiers. Now, no matter what rig or amp I'm using, the timing is perfect
and my Oscilloscope confirms this. Hot switching is forever gone.
-Paul, W9AC
----- Original Message -----
From: <N1RJ@pivot.net>
To: Amplifier Reflector <amps@contesting.com>
Sent: Monday, July 05, 1999 2:02 PM
Subject: [AMPS] RJ-1 relay etc
>
> My TS-940 produces RF output at 5.5ms after key closure. The T/R
> relay is driven from a waveform that is delayed 3ms from key closure.
> With the 2ms delay of the T/R relay, the switch signal to the amp is
> very close to RF output time. I found a signal that went high upon
> key closure and used it to drive a power FET switch. This gained me
> 5ms which is plenty of time for my QSK to work properly.
>
> 73, Roger
>
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>
>
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