CHP Primary / Extender

[jeremyapps]

Hey all,

I’ve been around a few CHP incidents recently and I’ve noticed that only when I’m close to the CHP officers my scanner switches to the Extender on P25. I was wondering why that is the case and what the differences are between the two channels.

Thanks a lot

 

[gmclam]

The purpose of Extenders is so an officer can communicate from his/her vest with their dispatcher. The radio traffic is relayed to/from their auto over the Extender frequencies. It is designed to be very short distance and therefore low power. There are multiple frequencies in order to support more than one officer at a scene.

There are lots of threads here on RR regarding CHP radios and such. Do a little searching and you'll fine more info than you have questions for.

 

[scannerboy02]

I was wondering why that is the case and what the differences are between the two channels.

The main VRS channel is used to repeat the low band radio to the portable radio and the alternate VRS channel is used to repeat the VHF/UHF/700/800 radio(s) to the portable. I am very much interested in how this setup may have changed with the new Kenwood radios.

A great resource for CHP radio system history can be found here.