Flex 6700 as Full Duplex Satellite Station 160M-23cm

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Attached are photos of my recently completed Flex 6700 fully automated (using FlexUSB) Satellite station. It will operate all bands 160M-23cm. 

The HF antennas and the other Flex 6600 station are not shown in these pictures but can be seen here if interested. https://www.qrz.com/db/W4AX

Making all this work seamlessly with a FlexRadio is a breeze.


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Mack McCormick, Elmer

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Posted 1 year ago

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Michael Walker, Employee

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Nice job Mack!  That is a work of geeky art!
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Seriously amazing.  Should work great when/if we get a Phase 3 satellite again. 

Spent time squinting at pictures, but interested in the details of your current 23/24 cm side.  Most transverters and amps are set up for terrestrial "1296" rather than the 1260-1270 MHz used for satellite ops.  (There is a rumor that DEM/Q5 has some special units being developed.)
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Dave Gipson

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Wow.. Beautifully done!

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John - K3MA

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Can you describe the software control side of the Flex 6700 automatic satelite station?
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Mack McCormick, Elmer

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I'll describe the FlexUSB setup and configuration. The SatPC32 uses standard CAT connections and I'll leave the configuration up to the AMSAT reflector.

I am using three USB Cables; LDPA, BCD band data, and Bit data. Here is the configuration:

The DEMI LDPA configuration is very straightforward

The USB bit cable to provide band data to the Array Solutions Bandmaster III which in turn controls the Array Solutions FilterMax V contest filter to allow legal limit on two separate antennas simultaneously on HF separate bands. (this filter is built in the my other Flex 6600)

Now the only remaining cable needs a bit more explanation. I am using this board to provide DC power to two BNC RF relays, one N connector RF relay, and to provide keying for the 222, 440, and 902 transverters. I am using this relay: https://www.amazon.com/gp/product/B0093Y89DE/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

Relay 0 - turns on the 432 BNC relay connecting it to RX B
Relay 1 - turns on the 902 BNC relay connecting it to RX B
Relay 2 - Provides keying for the 222 transverter
Relay 3 - provides keying for the 432 transverter
Relay 4 - provides keying for the 902 transverter
Relay 5 - provides keying for the N connector relay to switch between a 2M circular and horizontally polarized antenna.

Mast mounted preamps for 144, 222, and 440 are all Advanced Receiver Research preamps that automatically bypass in the presence of RF. The 902 preamp does not have that capability and a ARR sequencer is used to bypass the preamp and provide keying to the 902 transverter.

Not too complicated.



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Mack McCormick, Elmer

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I found an error in the bit cable. It should look list this:

0.       Activates RLY 1 when 432 MHz band selected

1.       Activates RLY2 when 902 MHz band selected

2.       Provides PTT to 222 MHz transverter

3.       Provide PTT to 432 MHz transverter

4.       Provides PTT to 902 MHz sequencer

5.       Activates RLY 3 when Slice H is selected on 2M and connects the transverter to 2M Horiz Polarized Antenna
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EA4GLI - 8P9EH - Salvador

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Great build!
I am using similar setup. I do have a couple of SmartSDR issues that I can only hope they will get corrected at some point.....

  1. Link VFOs to go on opposite directions or same direction. Like you can on the Maestro.

  2. Increase the bandwidth on FM RX (currently 24KHz is the max) to be able to cover NOAA signals (48KHz), instead of having to pipe IQ into another program to then send the signal into WXtoIMG.

  3. Slave TX ports to specific Slices and save them in a profile that I can recall. A profile per each sat.

  4. Recall profiles together. Call profile "Sat 1" and then have the option to ADD profile "Sat 2" as long as I have Slices available (8 on the 6700). This would allow me to work on several sats at the same time if I happen to be in their footprint at the same time.