[TenTec] ORION_ANTENNA_SWITCHING

[Geoffrey S. Mendelson]

On Wed, Dec 14, 2005 at 07:59:31AM -0500, George K wrote:
> I'm trying to think of some logic that I could outboard to provide this 
> function but nothing yet.
> The reason for all of this is to switch an LDG-1000 auto tuner on the output 
> of my amp from the beam, 20-10M, to my bank of wire 16--30M, antennas.
> I'm open to any ideas apart from manually switching the output of the LDG.

Here is what I think you are saying:

You want to connect the radio to an amplifier. Then connect the amplifier
to a tuner. The tuner gets connected to different antennas based upon which
band the radio is set to. Corrent?

If so then you want to use one antenna jack, and use the band switching
data to control a switch between the antennas and the tuner.

The way I would do it is to buy a simple process control computer, there
are many of them out there, often sold as "home automation" units.
It needs to have at least as many inputs as the band data and enough
outputs for the maximum number of antennas you want to switch. 

If you can't program in assembly languange you can get one that runs
basic or forth. They are easy to learn languages. You could also find
someone to program it for you, many hams are also programers or just
ask the teenager next door. :-)

A simple loop would be all that is enough as an example (in no particular
language):

Top:
	wait .5 seconds for band data to settle (optional)

	decode band data into band number
	
	if (band is 10m) 
		switch on beam
		go to Top

	if (band is 20m) 
		switch on beam
		go to Top

	if (band is 80m) 
		switch on wires
		go to Top

	(repeat for all bands)

	OOPS! don't transmit!!!

	wait 1 second
	go to Top:


A really neat RF proof box with band and antenna lights would make this
a wonderful addition to the shack. Depending upon the relay you use, you
could choose one from a resounding "clunk" when you change bands to
a silent one.

Another function, which would really complicate it but might be nice would
be when the band data changes to put the amp into standby, lower the ALC
to put out the minimum the tuner needs and transmit a short burst to
tune the tuner BEFORE you try to transmit. The down side is a random dit,
possibly over someone else's QSO, a disaster during a contest, but on an
empty band no big deal.

Maybe send your callsign instead of dit and check the receiver for a signal
first. 


Geoff.
-- 
Geoffrey S. Mendelson, Jerusalem, Israel gsm at mendelson.com  N3OWJ/4X1GM
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