Ham Satellite news

New DTMF mode on PSAT2

From ANS-122: PSAT2 (NO-104) VHF is alive and new DTMF mode:

Bob Bruninga writes: PSAT2 VHF awoke from an 8 month slumber on 26 Apr 2021. We have no idea why. Its telemetry looks fine. Volts between 6.2 and 7.0 volts (5 NiCds). Exterior temps between -18 and +22 C. See

PSAT2 will NOT be in APRS mode but a brand new experimental mode for DTMF uplink and VOICE downlink. So you preload your grid and callsign into a 16 digit DTMF memory in your radio and when the satellite hears this it will assign a QSO number and QSL the grid by voice and then also generate an APRS packet for collection by APRS operators. There is even a way to send back a DTMF QSL so you can make it a 2-way DTMF. contact. Successful DTMF grids and messages will appear on a special URL on the PSAT2 page (above). To QSL, you key in that stations 2 digit QSL number and then dump your pre-loaded QSL DTMF message.
Since this is the first time this transponder is on the air and because a
DTMF uplink takes maybe 4 seconds, we don’t want the uplink saturated by a bunch of newbees initially until we see if it actually works. So read the
docs and be sure you know what you are doing. There is a user operating manual available on the PSAT2 web page:

[ANS thanks Bob Bruninga, WB4APR for the above information]


Webmaster and member of the AMSAT-SM steering group.

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