Can you answer this question?

[convE36]

Canyon Lake Security uses frequency 461.3875 for their repeater output...

And uses 466.3875 (obviously) for the repeater input...

I was searching through random frequencies and found that I can also hear them loud and clear on frequency 418.7875...

Which is not one of their freqs and not on any site...

Why is that??? I remember a couple months ago I was hearing RSO traffic + control channel on some 900MHz freqs, someone on here explained why that happens, maybe the same thing with this? I am confused...

Thanks guys.

[brandon]

Sounds very similar to your 900 MHz image. 418 MHz would not be a valid range for Canyon Lake... that is where the feds hang out
The other freq besides the ones you listed for Canyon Lake is 464.875 D043

[convE36]

Sounds very similar to your 900 MHz image. 418 MHz would not be a valid range for Canyon Lake... that is where the feds hang out
The other freq besides the ones you listed for Canyon Lake is 464.875 D043

I dont understand the whole "image" thing...

[zz0468]

I dont understand the whole "image" thing...

It's easy. The RF frequency, plus or minus the local oscillator frequency creates the IF, or intermediate frequency. A receiver uses one or the other. The sum or difference frequency that is not intended to be used is called the image frequency. Low cost receivers frequently have a very sensitive response at the image as well as the intended frequency.

I'll put it in simple hypothetical terms... Say, you have a scanner with a 21.4 MHz IF, high side injection, and you want to receive a frequency of 450.000 MHz. The local oscillator would have to be 21.4 MHz above 450.000, which would make it 471.400 MHz. The 450.000 signal mixes with the 471.400 LO, creating the IF of 21.4, and the receiver demodulates the 21.4 IF signal. Now, suppose there was a signal at 492.800 as well. It's 21.4 MHz ABOVE the LO, so it would mix as well. Your receiver would hear it just as well as the 450.000 signal.

Hi end receivers take steps to eliminate image reception. Scanners take minimal, if any, steps, so the image signals frequently appear at displayed frequencies that make no sense.

*whew*