At 08:59 PM 9/7/2006, Lee A Crocker wrote:
>I was looking over the LDG website tonight and I ran
>across the LDG AT-200PC. The 200PC is an auto tuner
>that is controlled from the PC. It has 2 channels
>that allow for 2 antennas, and it remembers the tuning
>for each of those antennas.
I have several AT200PCs here. They're fairly nice.
>One thing that I miss in the SDR-1000 is the ability
>to have a second antenna such as a Beveredge on RX.
>This device it seems to me would make an ideal
>addition to the SDR-1000, as the software could allow
>the ability to choose the antenna, and the tuner could
>easily be controlled from PowerSDR.
A number of the rig control programs are able to control both tuner
and SDR1000 at the same time, using the CAT interface for the SDR1000
and the RS232 port to the tuner. I don't know if they have the
ability to send a command when you change from Tx to Rx or back,
which is what you'd need. The command protocol for the AT200PC is
pretty simple and documented in LDG's manual, along with sample code
in VB2003. You'd want to do something like:
On transition to Rx
Set Antenna to 1
Set tuning configuration to stored config #1 (bypass?)
On transition to Tx
Set Antenna to 2
Set tuning configuration to stored config #2
On frequency change
if we've been here before
Set LDG frequency to new frequency
if we've not been here before
Run tune sequence
As far as the actual tuner electronics go, it's pretty similar to
what's in the ATU for the SDR1000 anyway. LDGs tuners all pretty
much use the same topology and L and C values, just changing the size
of the components for the power level.
I have a VB2005 class for the AT200PC if anyone is interested. It's
only partly checked out so far, but at least it runs the tune
sequences and talks to the box to set L and C.
>I wonder if there is any development along these
>lines?
>
>73 W9OY
>
>__________________________________________________
>Do You Yahoo!?
>Tired of spam? Yahoo! Mail has the best spam protection around
>http://mail.yahoo.com
>
>_______________________________________________
>FlexRadio mailing list
>FlexRadio@flex-radio.biz
>http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz
>Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/
>FlexRadio Homepage: http://www.flex-radio.com
James Lux, P.E.
Spacecraft Radio Frequency Subsystems Group
Flight Communications Systems Section
Jet Propulsion Laboratory, Mail Stop 161-213
4800 Oak Grove Drive
Pasadena CA 91109
tel: (818)354-2075
fax: (818)393-6875
_______________________________________________
FlexRadio mailing list
FlexRadio@flex-radio.biz
http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz
Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/
FlexRadio Homepage: http://www.flex-radio.com
