I'm thinking of making the simple AM transmitter circuit described here. The idea is to use a crystal oscillator to produce the carrier (as a square wave) and then to modulate that by putting audio AC onto the power pins of the oscillator. An audio transformer is used to provide the isolation and impedance matching between the sound source and the oscillator. A better explanation of the same circuit is here.
Anyway, I'd like to replace the audio transformer by simply using a coupling capacitor as shown. I think this should work fine, maybe even better than the transformer. I'm not convinced the power at the clock output will vary as much using the transformer as I might be able to get by limiting the current to the clock into a range where the AC signal affects the output. I'm guessing that's at supply voltages below its 5v rating.
But I'd like some opinions. Do you see any problems with this strategy? Any advice? I want to be sure to not overload the headphone output of my iPod, which I think is 32Ω impedance. Should be safe, right?
Anyway, I'd like to replace the audio transformer by simply using a coupling capacitor as shown. I think this should work fine, maybe even better than the transformer. I'm not convinced the power at the clock output will vary as much using the transformer as I might be able to get by limiting the current to the clock into a range where the AC signal affects the output. I'm guessing that's at supply voltages below its 5v rating.
But I'd like some opinions. Do you see any problems with this strategy? Any advice? I want to be sure to not overload the headphone output of my iPod, which I think is 32Ω impedance. Should be safe, right?