I realize that thiis an old topic thread but I wanted to clarify this statement made by Yeti. Actually a balanced modulator IS used for AM in some rigs... an example is the President Lincoln/HR2510/HR2600. Also some Ham rigs used the BM for AM. This is done by unbalancing the balanced modulator to let some carrier through and bypassing the SSB 10.695 filter via diode switching. I have done this as a mod to an RCI2950 and an old Cobra base station. Need to have a wider 10.695 filter switched in for AM or there will be a lot of spurious junk in the output. But it does make very nice AM. You have to make the SSB bias on for AM also to make the final linear. AM/SSB CBs switch the bias for AM/SSB, collector modulators are more efficient in Class C. Since the AM is now modulated at low level all stages after the balanced modulator have to be linear or the end product will be distorted. Of course you have to address the audio bandwidth to get "hi-fi" AM. This AM mod eliminates all crossover distortion from negative overmodulation and allows any amount of positive modulation desired. Just food for though for all of you who like to experiment. As a final point... if you're still using the standard diode AM detector that all CBs have any modulation above about 80% is distorted, getting increasingly distorted the higher the modulation level gets... so a better detector is necessary to demodulate "supermodulated" AM without distortion.
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