I don't think anyone as really addressed on issue with hot switching.
That is when you interrupt the RF cycle ( probably more of a problem using
CW than other modes)
wide band clicks will be produced even if you should magically do it at
zero crossing.
Often we are concerned with our the problems we produce for
ourselves and do realize
what problems we create for others on the band.
73
Bill wa4lav
At 04:09 PM 11/15/02 +0100, Skram, Helge (MED) wrote:
>Re hot switching of RF-relays, I think it is a real problem, confirmed by
>own measurements.
>Modern tranceiver put our RF too fast for most relays. It may help but is
>not cured by switching RF relays directly by the PTT.
>
>A solution for SSB may be to connect the microphone PTT to the PA and with
>extra set or relay
>contacts or extra relay (slow) close the PTT in the Tranceiver. Then there
>will be no hot switching.
>
>For CW, the keyer must have a "VOX" relay to close the PTT in PA, that
>controls the transceiver.
>QSK can not be used.
>
>This solution will work on VHF/UHF where QSK is not used.
>
>
>LA6MV
>Helge Skram
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