Help me decide The PL519 tx project did not come through. Morphed into a cb amp instead. As I see it I have 3 options to realize a MW transmitter from. 1. Simple low power using 807 valves and 6ag7 buffer with dds oscillator. Have 500v transformer with 6.3v heaters rated at 300w. Add anode modulation to that using either the art-13 mod transformer or try some of the power transformers lying in the pile, or go the easy route with cathode modulation. Very inefficient, but easy to get going. 2. 813 final, modulated by 811's. Either use the ART-13 or the UTC S-22 mod iron (the S-22 is far bigger and heavier, but i'll bet the quality and durability of the ART-13 iron is superior) For this I would need a transformer delivering 900vac. Have non suitable at the moment except for a 32-0-32v unit capable of 540watts, which would be fairly easy to rewind to the needed voltages. 3. Go solid state class e.. Unfamiliar territory for me, but seems relatively easy. Order a bunch of IRF640's, copy the pwm modulator and pcb design from the fat-5 transmitter (hate breadboarding and dead-bug building) and use the aforementioned 540w transfomer with it's original windings. Looking for atleast 100w carrier.
Last nights listening and a visit to the pirate chat really made me want to start building right away....
Ok. Time for an update. The TX is finally alive Taking it easy with about 50w carrier at the moment but can easily be configured for 100w by changing taps on the HV transformer. Using Stretchy's pwm modulator and the rf deck consists of 2x2 fets in push-pull.
