You want a simple answer? Yes Yes Mostly The image signal is not really generated at all. The image is an artifact of the mixing in the receiver which produces the sum and difference frequencies of the desired signal and the local oscillator.
I am wondering what scanner you are using? Most scanners for the bands we use will have a first IF (intermediate frequency) of 10.7Mhz and will usually not see the +/- 455Khz image. They might see the +/- 10.7Mhz image depending on how well the receiver is designed and built. Single conversion receivers (especially small, light RC receivers) are likely to hear the image if there is a signal on that frequency and it may cause interferance if the signal is strong enough. Dual conversion receivers rarely have problems from image pickup. If your scanner is a single conversion then looking at the image frequencies tells you nothing useful because you can't tell if the signal is the image in the scanner or a real signal out in the air. This is a simple look at a complex subject that fills many books. It is possible to get into it a bit more but best to try and focus on your situation so you don't get overloaded. michael N6CHV AMA77292 On 5/11/06, Martin Usher <[EMAIL PROTECTED]> wrote:
Sounds like the scanner receiver is the problem. (You'd have to have some really weird transmitter circuitry for it to emit on those three frequencies.)
Its helpful to know the relative strengths of the signals. Martin Usher Cal Posthuma wrote: > Our club purchased a scanner. We are using a program on the scanner > which gives primary freq and + and - 455 image freq. > > When a tx is turned on the scanner picks up these image freq as well > as primary. > > I am thinking these are generated by the rx not the tx. > > Are they a problem? Am I correct?
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