We were just discussing our company's purchase of 3 new radios for 12.5hz compliance. (Resistance is Futile!) I had a o.O moment and thought....
City, county, hospital and EMS have all gone digital. I can't pick them up with my analog handheld scanner anymore. GPS runs on analog right?
Does digital and analog share the same banding?
Who am I bothering with my 25kHz?
It's kHz, not Hz of bandwidth involved here.
But to the point, yes any signal regardless of its modulation type in that bandwidth will affect any other signal trying to use that same/overlapping bandwidth. If it isn't the same kind of signal (FM, AM, FSK digital data, PSK digital data, GMSK data, whatever), it will look like noise to the other receiver and may be strong enough to prevent reception of the desired signal.
By analogy, think of files on your computer. The picture viewer doesn't know what to do with a dwg, mp3, or doc file, but they all take up space on the disk.
Those other services may have changed to a different frequency band when they went digital, or maybe not. Somebody is probably trying to use the spectrum.
