Or if you don't want even the tiny click of a reed relay (someone has
claimed it is not true QSK if you can hear a relay click) you could use
an optocoupler.
If the relay is fast enough, it is capable of real QSK. The reed switching
response time of all Ten Tec's I've ever used can safely be put into the
"real QSK" classification.
LED in optocoupler only needs a few mA, not enough to
bother that transistor, and no inductive kickback. Maybe even faster
than a tiny reed relay.
The opto-coupler must still interface into another RF switching device. I
don't know of any opto-couplers capable of cleanly switching RF, let alone
switching at the100 watt level.
Typically a lot faster than a reed relay, microseconds instead of
milliseconds.
Both reed and vacuum relay types can be shock-mounted to provide nearly
silent operation. PIN diodes can switch +2KW and these devices are about as
fast as QSK gets. However, without an external tuning network, PIN diode
switching designs for high-power amplifiers are safety limited to about a
2:1 VSWR.
Given the repeated failures in that particular Omni VI, there's something
going on that's external to the radio.
Paul, W9AC
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