In the last few days I heard traffic on 155.970(DOT Blue cars), 155.445(CIS), and 154.920(Purple channel) in the Des Moines area.
The DOT blue car and CIS channel were analog transmissions. The purple channel traffic was P25. I wonder if the troppers switch to "CIS" when they can't make out each other on their P25 car to car channel due to distance?
All the traffic heard, on all three frequencies, was your general officer to officer traffic. It has been some time since I have heard anything on any of the three frequencies listed.
Tim K.
The DOT blue car and CIS channel were analog transmissions. The purple channel traffic was P25. I wonder if the troppers switch to "CIS" when they can't make out each other on their P25 car to car channel due to distance?
All the traffic heard, on all three frequencies, was your general officer to officer traffic. It has been some time since I have heard anything on any of the three frequencies listed.
Tim K.
