[VHFcontesting] keying amps

[John D'Ausilio]

Easy fix for that, Rick, is to hard-key the amplifiers. You can gate
to the right amp with a toggle switch (error prone) or come up with a
band decoder to gate PTT to the amps. For that matter, you can just
hard key both amps .. protects the front end on 222 at the same time.
Too much rf in the jitney to use rf-sensed ptt ...

de w1rt/john


On 3/5/07, Rick R <rick1ds at hotmail.com> wrote:
> Far from being an expert, I have a similar problem when I transmit on 6m
> (FT736R+160W amp) in my rover vehicle, it keys up the 222 amp (although no
> output, as there is no input signal on 222). I am sure this occurs because
> there is enough RF out on 6m that some of it gets into the amp relay (or at
> least the RF sensed section that can key the relay on 222 amp). Might some
> of the problem be that high output from one amp is triggering the relay
> circuitry on the other? This is the only amp and band combo that I have this
> problem. Both amps are hooked to the Yaesu FT736R. Of course the antennas
> are in close proximity in the rover, although most VHF/UHF stations have
> similar antenna proximities. Rick, K1DS
>
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