Astron SS-30m Service and Repair Notes
by KD7KDO
Presented 20 April 2026
Paul's presentation on testing of Norm's, aa7oo, Astron SS-30m 12Vdc switching power supply. Knowing how a switching power supply works can be a challenge. The subject PS failed during FD 2021, taken out of service, and replace with a spare. Norm attempted to troubleshoot. Official Astron schematics and documents were found online. Understanding the schematic with respect to how a SS really works involved watching many U-Tube sessions. Note so Quick. After many hours of testing, Norm became frustrated and brought a SS PS Designer, Paul kd7kdo, into the Process for help & guidance. Still not so simple. Paul suggested the Astron be transferred from Norm's test bench to Paul's after much pleading from Norm.
This presentation contains safety and testbench tools to consider before opening a Switching Power Supply. The testing and analysis used is specific to the Astron SS 30 but can be generally applied to others.
Paul Bennett, kd7kdo