[Elecraft] Sequencing a chain of equipment with a K2 at the head.

[Guy Olinger, K2AV]

Well, that's an interesting question. "Should" implies blame. Or who
owes who what. Or that someone has done something "wrong".

I'd rather be pragmatic and avoid replacing bandswitching and final
tubes costing some hundreds of dollars.

I have also seen vacuum-relays ruined by hot switching. It takes
longer, but the arcing destroys their points as well.

Even pin diode circuits can be ruined. I've managed to do that myself
before I figured out what was going on.

A sequencing circuit as an option or personal addition to a K2 is low
level, cheaper and surer solution than the other modifications, and is
a universal answer.

Insisting on doing everything in the amps seems rather the hard way.

73, Guy


----- Original Message ----- 
From: "Vic Rosenthal" <vic at rakefet.com>
To: "Guy Olinger, K2AV" <olinger at bellsouth.net>
Cc: "Jay Kesterson" <k0gu at verinet.com>; <elecraft at mailman.qth.net>
Sent: Saturday, June 05, 2004 5:52 PM
Subject: Re: [Elecraft] Sequencing a chain of equipment with a K2 at
the head.


> Guy Olinger, K2AV wrote:
>
> > Dot paddle low *OR* dash paddle low *OR* 8R low gives pass-long
low.
> > The OR function can be done with diodes, but it would need to be
> > buffered because nearly all of the downstream devices require you
to
> > GROUND *their* voltage.
> >
> > And this will only work with devices capable of "QSK" state
switching
> > speeds.
> >
> > If you add a variable VOX delay style "hang", more devices can be
> > switched, but hardly all.
>
> I don't recall how long the delay from the assertion of 8r to the
> appearance of RF is, but it was long enough for the vacuum-relay
> switching my homebrew amps as well as the PIN diode switching in my
> commercial model.  The question is, should the exciter have to worry
> about slow el-cheapo changeover relays, or should the amplifier be
> designed (or modified) to switch reasonably fast by today's
standards?
>
> -- 
> 73,
> Vic, K2VCO
> Fresno CA
> http://www.qsl.net/k2vco
>
>