Hi Ev,
If I were doing this with audio as you indicated you want to do, I would
use a Raspberry Pi with a USB GPS Dongle to play the audio files with
GPS-aligned timing, rather than avoiding the WSJT modes. The RPi has a
3.5 mm jack for audio out at line level, and you could feed that into
your transmitter audio input.
A 4 GB Raspberry Pi (which is what I used) is $55 at adafruit
https://www.adafruit.com/product/4295
and the GPS USB dongle is ~$17 at Amazon
https://www.amazon.com/Navigation-External-Receiver-Raspberry-Geekstory/dp/B078Y52FGQ/
I wrote a simple beacon script using python that cycles through 3
different audio files, each starting at the top of the minute. The
starting times are plenty precise, consistently less than 10
milliseconds off the minute.
You could use one wav file for Q65-60C, one for CW, one for SSB as you
suggest, or you could make it as complicated as you want, starting files
not only at the 0th second of the minute but also at the 15, 30, and 45
second marks for the shorter modes, and you could mix modes within any
given minute and timing would be preserved.
The simple python script for a beacon cycling among 3 modes, each
starting at the top of the minute is at the URL
https://w3sz.com/BeaconPlayAudio3.py
The python script starts automatically when the RPi boots and the unit
operates as a black box with no need for user intervention or internet
access.
In this test I used for the 3 modes Q65-60C, Q65-15C, and Q65-15A only
because I had audio files for those modes in front of me so no work was
required.
After I click "Send" on this email I will start making a simple document
with the "prescription" describing the details on setting this up as
well as an illustration of the results. The document should be at
https://w3sz.com/AudioBeaconDescription.pdf by daylight tomorrow
(Tuesday 5/21 EDT).
It might seem tedious in the telling but it would take less than an hour
to set this up from the time the RPi box arrived in the mail. If you
are interested in doing this but not comfortable with the details, I
would be happy to get the RPi set up and running so that all you had to
do was connect the power, plug in the GPS dongle, and connect the audio
cable from the RPi to the transmitter audio in.
73,
Roger Rehr
W3SZ
On 5/18/2024 02:37 PM, Ev Tupis via wsjt-devel wrote:
Hello all,
Later this fall, I hope to install a constellation of multi-mode VHF+
beacons. CW, SSB, and MD (machine decodable) all in the same
transmission.
My intention is to record the audio digitally (MP3) and drive a
multimode radio in "SSB" mode, playing it over-and-over.
Is there a WSx mode that does not require the TXing and RXing stations
to be timeslot locked?
I can always fall "back" to PSK31/63 or RTTY, but would like to
explore the WSx approach a bit before I do.
If this is off-topic, I would be happy to receive off-list input, of
course.
Thank you for the work that you do.
Sincerely,
Ev, W2EV
_______________________________________________
wsjt-devel mailing list
wsjt-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/wsjt-devel
