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No. Reflections are linear phenomena, so they don't generate signals on
any new frequencies, or convert the frequencies of signals. Diodes, on the other hand, are nonlinear devices which can do that. They can create harmonics from existing signals, and they can mix signals together to produce signals on frequencies that equal the sum and difference of various multiples of the signals being mixed. Likewise, a strong signal or signals can drive a poorly-designed receiver front end into a nonlinear region for the same effect. It's easy to test for the diodes. Find a suspected mixing product, and see if it goes away when you disconnect the diodes. To check your receiver front end, put an attenuator between the antenna and the receiver. A 500 ohm potentiometer should be adequate for the test. As you increase the attenuation, receiver mixing products will drop in amplitude more quickly than valid signals. At some amount of attenuation, you should hear only valid signals. Roy Lewallen, W7EL mike wrote: After thinking about this a little more. What if my current impedance mismatch between my antenna and transmission line is actually causing reflections which are noticed by me as images on other frequencies? Might a signal coming in on 3200 khz echo end to end back to 2300 khz? This seems probable and the diodes may not be causing it at after all. mike |
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