Tuesday, January 10, 2012

Propeller QRSS and OPERA Beacon

My Propeller 30m QRSS and OPERA Beacon Station

Currently I am running the Propeller; on QRSS at 10.140080mHz, and OPERA at 10.150380mHz, in single program time sequence order, with a 6 minute Receive-only delay between beacon transmit sections.

PUB Main



      RFFreq := Qrss_Tx_30m

      RFFreq := Opera_Tx_30m


The time sequence is controlled via a single program, but eventually my goal is to simulcast, both QRSS and OPERA Beacons during the same Tx Window, leaving more time for Receive and reporting.

And, then I plan to add WSPR Tx to the mix :-)

With the 8 COG's (processors) of the Propeller, it should be all very do able. It is, . . .  just software!

I also want to provide for TX-Relay control or Receiver Power Control, as my poor Ensemble RX receiver (on another antenna) is currently having to swallow the near field 62.5mW's of the Propeller's After Burner, which is not good. Also, a TX-Relay would allow for TX and RX to use the same (my new higher) antenna.

As stated, I am currently only operating on 30m, but the Propeller can operate on any HF Band and I plan to do so. But a Band switched Low Pass Filter is necessary, I have one sketched on a napkin, but have not committed anything to a protoboard, yet.

Note: my custom "delay" routine had to be modified to accept large delay values. There maybe a better approach, but this works for now.

PUB delay(ms)
  repeat while ms > 10000
    waitcnt(cnt + clkfreq * 10)
    ms -= 10000
  waitcnt(cnt + clkfreq/1000 * ms)

UPDATE: I found a published "delay" routine, and now using it, see the next post.

I am just have fun with Beacons and the Prop.


1 comment:

  1. I'd like to make a frequency-agile beacon with an LCD menu to allow setting the frequency etc. I've a lot to learn about the Propeller chip before that is possible though.

    Re comments made elsewhere about phase noise on the Propeller output do you think it's really a problem?