Sounds like an 800 mhz. frequency is being used. Typical MDT ranges
are 453 mhz., 460 mhz. and 853-870 mhz. If you hear a constant data
control signal that is somewhat high in tone that usually is a MDT
signal. But it depends on the manufacturer. Other MDT signals may have
a different audio control sound. All are annoying to listen to.

wrote:

Talked to a MEtro LEO yesterday and he told me the patrol units
have upgraded to a new data terminal system.
The antennas consits of two units about 2" in diam, and about 3"
high. They are mounted on the trunk of the cruisers about 3'
apart. I have not had a chance top look at the terminal or display
yet.
Does this system sound like anything anyone else has had before?
Terry