Hi Bob, delighted to hear from you. What I was really wondering was if there
were somewhere in the software that allowed the linkage between pin 14 state
and left or right to be reversed. My guess is there is not.
Having said that, the next solution is to use a transistor buffer to reverse
the state just as you suggested. For something that's my own little
idiosyncrasy I'll certainly take that approach rather than suggesting yet
another s/w change!
Thanks & 73 de Larry K7SV
I may be missing something in what you are wanting to do here! The way I
see it, you just need to invert pin 14 state using a transistor buffer so
that when pin 14 is true your relay is not energised.
73
Bob 5B4AGN, P3F, ZC4ZM
----- Original Message -----
From: "Larry Schimelpfenig" <k7sv@va.prestige.net>
To: <writelog@contesting.com>
Sent: Friday, September 20, 2002 1:49 PM
Subject: [WriteLog] SO2R A/B ASSERTION
> If this appears to be a bit anal, so be it, but I want to make sure my
> conclusion is correct, so I turn to this body of expertise!
snip snip
> Here's the rub. I would like the radio on the left to be keyed through the
> normally closed relay contacts. There are two reasons for that. First, if
I
> have some sort of failure, so the a/b function stops working, I'd like to
> have the predominent radio available. Second, it just seems to make sense
> that the more active radio would be used with the relay in the normally
> closed state.
>
> >From what I can tell, the software is set up so that the right radio icon
is
> tied to parallel port pin 14 in the non-asserted state (relay is normally
> closed). Which means that when the left radio is selected, the left radio
> icon illuminates, and pin 14 is asserted.
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