The HF-2500Dx does not have a TX EN "ready for transmit" output. As such I
would have to assume the high speed switching employed in the amp is
engineering to handle the exciter power on key up.
Or, the Omni VI delays the generation of RF when the RELAY function is
turned on. My manual does not describe this as clearly as I would like
it to. It does say that when the relay function is turned on, the SLOW
QSK delay setting becomes the relay hang time. It does not say that when
the TX OUT to TX EN jumper is in place and the relay function is turned
on there is a delay time between key down and the relay energizing and
the beginning of RF output. Those Ten-Tec guys are pretty clever, so I
would guess that they thought of this.
Using the RELAY to key the amplifier certainly will work, and provide
some degree of "QSK", though not quite as good as using the keying loop
method. There are some on this reflector who claim that if a relay can
be heard, it is not QSK at all.
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