[Elecraft] K2 is break-in only on CW?? Part II

[Jerry Summerall]

The 8R line delay is not long enough to hold the last one or two relays on
my DEMI sequencers especially when running 15-20 WPM CW. I don't believe it
is hurting anything but I hate to hear the relays clicking continuously
while operating. At the same time, after using QSK CW, going to semi break
in is sort of annoying.
----- Original Message ----- 
From: "Don Wilhelm" <w3fpr at isp.com>
To: "Jay Kesterson" <k0gu at verinet.com>; <elecraft at mailman.qth.net>
Sent: Saturday, June 05, 2004 4:25 PM
Subject: Re: [Elecraft] K2 is break-in only on CW?? Part II


> Jay and all,
>
> There certainly IS a line in the K2 that can be used for sequencing
> switching of transverters and other external devices.  The 8R line becomes
> active about 20 ms before RF is presented at the antenna jack, and the
> drop-out time can be adjusted via the K2 menu - so to my way of thinking,
> the needed sequencer is already built into the K2.
>
> The KPA100 amplifier keying output follows the state of this 8R line, and
> the signal is used in the K2 to Elecraft transverter connection (KIO2) to
> switch the Elecraft transverters.  For those who are driving non-Elecraft
> devices with the base K2 (QRP), I suggest you look carefully at the 'K2
> External Power Amplifier Keying Circuit' shown on the Elecraft website -
> Builder Resources area, then select Application Notes, Eric originally
> designed it for use with an external amplifier, but can do the same job
with
> external transverter equipment.
>
> I believe that easy-to-build keying circuit will do the external switching
> job you need - OTOH, if your external devices need more than 15 to 20 ms
to
> become properly active, you may still be in trouble, but that IS a
> relatively long time period, even for relay operation and you may have to
do
> some work on the transverter end to make it switch faster.
>
> 73,
> Don W3FPR
>
> "Life is what happens when you are making other plans"
> (John Lennon wrote it in a book, Mike Cross used it in a song - I don't
know
> who was first)
>
> ----- Original Message ----- 
>
> >   Thanks for all for the replies to my question. My concern is using the
> > K2 with V/UHF transverters, amps and preamps (some mast mounted). These
> > are usually controlled with a sequencer that hard keys the radio last.
> > In certain setups accidentally bumping the paddle and having the rig
> > xmit could damage equipment down stream. I can use the PTT line from the
> > sequencer, that would normally be used for hard keying the rig, to key a
> > relay that doesn't allow CW to get to the K2 till all the up stream
> > equipment is ready. However I use a foot switch and headset, that gets
> > switched to three different rigs, on SSB. The footswitch is used to turn
> > on the sequencers during both SSB and CW operation.. On weak signal VHF
> > we often switch between SSB and CW. If I use PTT, from the sequencer, on
> > SSB I haven't figured out a way to easily (automatically) disable the
> > SSB PTT line on the K2 when I switch to CW. Any ideas, beside unplugging
> > the mic connector or otherwise manually disabling the mic PTT line?? Is
> > there some signal point inside the K2 that is active or grounded only
> > during CW that could be used to possible drive a relay to disconnect the
> > SSB PPT line while in CW??  Or better ideas??
> >
>
>
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