mandag den 1. april 2013

SSPA for 2 meters - project about to finish

Since last time, I have performed the SSPA smoke test. I adjusted the bias of the LDMOS transistor and set it to 3.5 A drain current at 48 V DC. Some heat was developed, but the cooling system could easily deal with it. Rf input and RF output were both connected to 50 ohms resistors. No oscillation was observed, which is good. Conclusion: so far, so good. Smoketest passed.

Many components, cables, relays, fuses, a sequencer, a high-current switch, and so on are used in the SSPA. It takes considerable time to mount them and connect the wires. As this is a prototype, some errors will happen in between. You learn from your errors - but they consume time. Today I can happily tell you, that the project is soon to be finished. The end is in sight!


One of the SSPA sidepanels seen from inside the cabinet.
The picture above shows how one of the side panels is equipped. Clicking the picture will make the text on the picture readable.

73 from OZ1BXM Lars Petersen  Visit my homepage: www.oz1bxm.dk