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The RF Workbench / Modulated 5W NS40
« on: September 02, 2016, 2012 UTC »
I met a guy at a bar a few months ago and we were talking about the FM radio on the shelf. Anyway, it ends up he was a ham. And at the time, he had a 5-10W transmitter that was meant for morse code, the NS40:
http://www.4sqrp.com/NS40.php
He mentioned that he modulated the NS40 transmitter using the schematic shown below. He's been testing it on a dummy load using an .MP3 player with pre-recorded speeches of him giving his callsign and calling CQ. He said he could get audio out. Also the audio is copied better if its compressed and limited. But he doesn't think its modulating very well and he wants to know why. He told a sad story of how his favorite car audio amplifier was destroyed. It was a 100w amp. He used an .MP3 player as input and he kept turning up the amp's output that went into the transmitter. Eventually he was getting good power out as shown by the swing on the tuner's meter. But the amp got hot and died. Any idea what might be the problemo?
http://www.4sqrp.com/NS40.php
He mentioned that he modulated the NS40 transmitter using the schematic shown below. He's been testing it on a dummy load using an .MP3 player with pre-recorded speeches of him giving his callsign and calling CQ. He said he could get audio out. Also the audio is copied better if its compressed and limited. But he doesn't think its modulating very well and he wants to know why. He told a sad story of how his favorite car audio amplifier was destroyed. It was a 100w amp. He used an .MP3 player as input and he kept turning up the amp's output that went into the transmitter. Eventually he was getting good power out as shown by the swing on the tuner's meter. But the amp got hot and died. Any idea what might be the problemo?
