Skip to main content

CatSat Team Demonstrates First QSO on C/X-Band Linear Transponder

April 26, 2026
A composite image of the 6.5-meter Tech Park station and the 1-meter Radio Ranch station

During the second morning pass of April 26th, 2026, CatSat team members successfully completed a bi-directional QSO (station-to-station contact) through the C/X-band linear transponder onboard the spacecraft. To the team's knowledge, this is the first time that a QSO has been completed at these frequencies through an orbiting spacecraft!

The two stations involved were the Radio Ranch 1-m ground station (Maidenhead locator DM42og) and the Rincon Research Corporation and University of Arizona's Tech Park 6.5-m ground station (Maidenhead locator DM42oc). These stations are separated by about 12 miles of physical distance.

Contact was steady and strong throughout the pass. Messages were exchanged by Morse code and included the callsigns of some participants (KT7D, WA3ZXH, KK7IOV) and a signal strength report.

The team hopes to continue demonstrating this link and providing this service to the larger Amateur Radio community until the end of CatSat's mission. More information can be found in the announcement post.