The US Naval Academy has received IARU satellite frequency coordination for HFsat, a 1.5 U CubeSat with a 15- to 10-meter linear transponder with a 30 kHz bandwidth (uplink 21.4 MHz, downlink 29.42 MHz). The Mode K configuration is reminiscent of the old “RS” series of Russian satellites.

The CubeSat will also carry an APRS digipeater on 145.825 MHz. HFsat is a project to demonstrate the viability of HF satellite communications as a back-up communications system, using HF radios found in a typical Amateur Radio installation or frequently used to support disaster and emergency response communication.

“HFsat will be gravity gradient-stabilized by its full-sized 10-meter half-wave HF dipole with tip masses,” said Bob Bruninga, WB4APR.

A standardized CubeSat VHF communication card based on the popular Byonics MTT4B all-in-one APRS Tiny-Track4 module for telemetry, command, and control is under development at the US Naval Academy. US Naval Academy students are working with Bill Ress, N6GHZ, on the HF transponder card.