[na-user] NA vs CT using OMNI 6+
Tue, 16 May 2000 10:38:32 -0500 (EST)
From: IN%"email@example.com" "k8cc" 15-MAY-2000 19:01:23.74
Subj: RE: [na-user] NA vs CT using OMNI 6+
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Date: Mon, 15 May 2000 19:55:48 -0400
From: k8cc <firstname.lastname@example.org>
Subject: Re: [na-user] NA vs CT using OMNI 6+
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At 11:02 AM 5/15/00 -0500, you wrote:
>Thanks for the response. I tried building up a switching box for the keyer
>using some of the ideas from the 2000 ARRL handbook. I use the TopTen
>style single transistor to key the transmitter from the parallel port and
>use a 4PDT relay to switch the collector of the transistor to the appropriate
>radio, using the radio select bit on port 1. However, I get a "pop", of
>full power when I select a radio! Just a very short burst, but have not
>been able to clear it up (yet?). My physical coordination is not too hot -
>it took me the better part of the weekend to drill holes in a minibox,
>wire up the relay and switching transistor, and keying transistor.
>Sure would be nice if the transmitter keying for each transmitter were on
>separate LPTs along with the antenna switching. Is there some reason that
>I guess I'll drop by and bother you in your Dayton booth.
>Terry Zivney, N4TZ/9
Is this with CT or NA? We've never seen this problem using NA, and a bunch
of guys (including me) have SO2R setups with a relay switching the keying.
THIS PROBLEM is with CT - I don't have NA (yet) - The box works OK without
the burst of output if I use clipleads, even with contact bounce, to key
the relay in the box, but when CT on LPT1 is used, I get the burst of
output whenever I switch radios with the "." key. END OF RESPONSE
Relay coils generate transients when they switch that can be suppressed by
placing a 1N4001 diode across the coil - cathode (banded) end towards the
positive side of the relay coil.
We don't have a booth at Dayton, at least like we did back in the LTA days
with K3LR. Radio Bookstore sells NA, but there's not enough for me to do
to spend the weekend hanging out there. I kinda miss the opportunity of
meeting guys who would come by the LTA booth.
You might catch me at the MRRC "Contester Suite In The Sun", fleamarket
spots 3858-3860, or at the big hospitality suite at the Crowne Plaza
hotel. I'll also be at the MRRC club meeting, held at 12:00 noon in the
Hara Arena stands above the Cushcraft booth.
Administrative requests: na-user-REQUEST@contesting.com