> The Ameritron and some Alphas use PIN diode QSK, which is
> very fast and will work fine... if the transceiver timings will let it.
Hi,
And thanks to the several commenting about my question,
re: SSB and hot switching.
I have the Ameritron QSK-5 switch; same circuit as can be
built into some of the Ameritron amps (all designed by W8JI,
the QSK-5 circuit, I mean). Anyway, had not been using it
when in the SSB mode; now will be, hi.
This gadget rcvs a key down signal, in my case, directly
from either my key or my PTT button; it immediately closes
the T/R relays in the linear and keeps them closed for a
long period of time: until around 4 or 5 seconds after the PTT
line is released or after the transmission of QSK CW has
been over for a similar period of time. All other T/R
switching is "by-passed" into QSK-5 device, and goes on
via high-power PIN diodes; can handle up to around 2.5kW
per specs. The device will NOT allow an RF signal from
the transceiver to enter the linear until after the PIN diodes
are set on by the initial key down sense line signal. Both the
linear output power and the incoming rcv signal pass via
the PIN's as long as the QSK device is operating; while
the linear mechanical relays are held closed throughout
a QSK QSO.
A neat gadget, though a bit complex to get all set up; four
coax connections on the back of the unit as well as three
transceiver condition "sense" lines and the relay closing
line to the linear ( depending upon your transceiver, some
splitting/isolating diodes might be needed in these lines).
I found it a challenge to at last understand
what the manual author had in mind as he constantly
refers to the "Transceiver QSK line"; turns out this is
just the usual coax from the transceiver to the linear, hi!
Why not just come out and say that?
Anyway, this is another solution to the hot switching issue;
I just had not realized that I should also be using it during
the SSB mode.
Thanks again to all, 73, Jim KH7M
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