Voice Channel on Salem County TRS

[ayaresr]

While scanning the Salem County Trunked Public Safety system, on several different scanners I have noticed them picking up a frequency of 414.xxx. I believe it is 414.3500 but can't remember the exact last four digits. The scanners identify it as a Voice Channel. Anyone know what may be causing this? The system normally operates 501.xxxx rx and 504.xxxx tx. Thanks for any insight.
Ryan

 

[crazyboy]

If the base/step/offset is not programmed correctly in your scanners it will do this.

 

[ayaresr]

That seems to have fixed it. I must have skipped over that part when I programmed these trying to get done too fast. What causes the scanner to do that? Is the scanner mis-interpreting the data the control channel is giving it? Or is it using what was programmed and based on that it looks to the wrong frequency?
Thanks for the quick reply, Ryan

 

[robbinsj2]

What causes the scanner to do that? Is the scanner mis-interpreting the data the control channel is giving it? Or is it using what was programmed and based on that it looks to the wrong frequency?

Your scanner was using preset base/frequency/offset and, based on that, it looked to the wrong frequencies. On Motorola systems, the scanner gets a channel number from the control channel. It then performs the following function to determine the frequency: (Ch-O)*S+B, where Ch is the channel, O is offset, S is step, and B is base. Obviously a small error with either O, S, or B stored in the scanner would result in a wrong frequency.

Jim

 

[ayaresr]

Makes sense. Thanks for the explanation.
Ryan