One sided communication. Any thoughts?
The Missouri Highway patrol uses half-duplex operation.
This means the base transmits on one frequency and the mobiles transmit back on a different frequency.
In your case, Troop D transmits on 42.06 to the cars, and the cars transmit back to them on 42.22.
The cars can also chat back and forth to each other using 42.06 as both transmit and receive in simplex operation. In simplex mode, they are also able to hear Troop D, but Troop D isn't bothered with car-to-car chatter.
They most likely use 42.0 for car to car as well. (statewide car to car)
While troop D has other frequencies in their list, those are probably the 3 most active in the low band in the Springfield area.
Low band is a tricky animal, since few scanner antennas made today favor the low band.
There are some relays which repeat the 42.22 frequency......They should be in the database toward the bottom of the list....These can be tricky as well, because they are low power and not really a repeater as most people know them.
I get the dispatch perfectly, but that is all I hear
Monitor 42.22 alone for a while (not scan), and see if you hear cars calling Springfield every now and then, and then decide how bad you want to listen to them.
Monitoring the MSHP is do-able, but not easy.....It pretty much requires a dedicated antenna(s) and radio(s)
Another thing to consider is how many troopers are inside the Springfield city limits during their tour. In Kansas City, I believe many traffic accidents are handled by KCPD and not the highway patrol. It's rare to hear an HP car inside the I-435 loop south of the Missouri River.
