The only real difference I've heard is that on some strong signals you can occasionally hear the unwanted sideband mirroring the intended AFSK signal. This signal is at a level reduced by the unwanted sideband suppression characteristics of the transmitter involved and separated by twice the modulating tone frequencies. This might put the two signals over 4 KHz apart, making it not apparent who the culprit is. It's pretty easy to see the problem with a panadapter. Note that some current radios (for example. IC756ProIII) only rate their transmitted unwanted sideband suppression at -40 dB (K3 is -50 dB). Some older radios are much worse. An unwanted sideband of -40 dB from a 1.5Kw signal would be 150 mW. I've worked DX with less.
On 6/13/2010 17:07 PM, N1JM wrote: > In real world operating, has anyone really experienced a difference or could > tell a difference? > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
