One last comment on this subject. I can appreciate the hot switching problem
but the reason I put up with a little longer pickup delay is that the keying
transistor in my exciter would not quite drive the keying relay in the PA. The
stand by switch for me was an free-bee. The real point for my case was that I
needed something to increase the current capacity of the keying line. I suppose
I could have used another transistor in cascade with the one in the exciter but
I now have a couple of spare contacts to use to light the "ON THE AIR" sign. :)
I don't usually start talking before the relay clack is dead in my ears anyway.
I suppose it's from all those years of using dynamotor powered transmitters.
- Bill
On Feb 2, 1:03am, measures wrote:
> Subject: Re: [AMPS] SB-220: Operate/Standby Switch
>
> >
> >At 02:07 PM 2/1/01 -0800, Bill Putney wrote:
> >>
> >>Eric,
> >>
> >>My Henry 2KD-2 doesn't have a standby switch either. Also the relay driver
in
> >>my exciter is a transistor which would marginally drive the keying relay
> >in the
> >>PA.
> >>
> >>I solved the problem by getting a little box that sits on the desk next to
> >the
> >>exciter. A small relay in the box takes the keying line from the exciter
> >>through a miniture toggle switch that acts as a operate/standby switch for
> >the
> >>PA. The contacts then drive the keying line to the PA. I don't have to
worry
> >>that the exciter driver transistor will be damaged and the box has become a
> >>place to put all the little things that I needed in the station (a matching
> >>transformer for a desk mike and a jack for a key that remotes the jack
> >from the
> >>back of the exciter that's hard to get to).
> >
> >Ah, so the idea is to leave the filaments on while transmitting through but
> >not using the amp. Got it. In that case, I'd suggest that instead of
> >using a relay to switch the keying line (if I understand Bill's set-up
> >correctly), that you just use the toggle switch itself to open that line in
> >"standby" and close it in "operate". Cascading two relays will only
> >exacerbate the problem the SB-220 has with hot switching by delaying its
> >T/R relay closure.
>
> Amen
>
(...)
> - Rich..., 805.386.3734, www.vcnet.com/measures.
> end
>
>
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>-- End of excerpt from measures
--
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# Bill Putney - WB6RFW | My repeater:443.400 Mhz-100 Hz #
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# billp@wwpc.com - (510)531-2412 | Go figure... #
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