I have an old Galaxy Saturn base unit that Im looking to do FT8 on. Looking at the cables in the list Im not sure any of them will work. Any suggestions?
Currently there is no store cable that matches this transceiver (GX16-4?).
Here’s the schematic of the mic connection:
The potential issue interfacing Digirig is that a double throw switch is involved to transition from RX to TX. Digirig’s PTT circuit is equivalent is normally open single pole. We should be good if radio can tolerate TX keyed up while RX is also enabled, but it’s unclear if that’s the case.
Another thing to consider is that from the specs it looks like VFO can be set in 10KHz increments while radio’s range only covers ham radio’s 10m band with FT8 frequency at 28074 KHz. Will you be able to tune in?
Yeah… I can tune as high as 28.350 so FT8 freq is fine. I hooked up a 1/4" to 3.5mm to the PC and was able to receive some signals OK.
Can you tune to 28.074 specifically?
Yes I can… last night I had the Galaxy tuned rite to 28.074. At the same time I had a SDR dongle tuned to it also. Same signal on both (sounds the same… start and stop the same). I ordered a patch cable to go from the rigs rear panel ext spkr jack to my PCs audio in and Ill see if I can decode FT8 signals that way. If I can hear the rite signal through the rigs speaker it should work fine. Now the PTT is still in question…
Great. Now, the radio should key up when pin 3 is grounded (connected to 1).
The question is: does the radio actually need pin 4 grounded in order to receive. You can test that by disconnecting the mic and checking if you still receive. If you do then it should be smooth sailing from then on with following connections:
MIC pin 1 → 3.5mm TRRS sleeve (GND)
MIC pin 2 → 3.5mm TRRS ring 1 (RIG_AFIN)
MIC pin 3 → 3.5mm TRRS ring 2 (RIG_PTT)
PHONE tip → 3.5mm TRRS tip (RIG_AFOUT)
Yep… with the mic unplugged the rig still receives just fine. I know some of the Cobra CBs go silent unless there’s a mic plugged in. Well… you have been very helpful indeed. Many Thanx… I’ll keep you informed as I progress.
I got my cable made and hooked up to the DR. What (if anything) do I set under rig control. I tried test ptt and got a long error for hamlib… Im using WSJT-X
OK I needed to grab a driver for the UART and PTT test seem to work…
Rig control in capable radios is available with serial cable connection.
It’s not the case here so select “none” or equivalent option in the rig control settings.
Just wanted to say Thanx! 1 month later I have over 300 QSOs in 52 countries on this old rig. Couldnt be happier!
Thanks for sharing. Happy to hear that!
@Styx_N_Stones Congratulations. I really appreciate when someone extends the capability of older equipment.