The spacing between frequencys. For example the aeronautical band from 108MHz to 138MHZ is 12.5KHz or 25KHz depending who you ask. Most bands have defined spacing. Nowhere is this truer then the public safety bands where narrow band rules supreme with 6.5KHz spacing. The scanner is usually preprogrammed with presumed spacing but for most scanners, this is user programmable as well. I'm sure somewhere on the RR site is a chart showing the most commonly accepted spacing for all the bands.
If i am running a vhf 150 to 174 and a 450 to 470 search where should it be. When I loaded it back from my scanner to my pc it showed up auto, then i played with it a little and now im picking more up! I looked in marks scanner page but doesnt take about this
I don't know. Inside those blocks you just specified, the are several spacings. I suppose to just experiment and see what works for you. I think it is probably better to search more narrowly defined ranges since an error in spacing could cause the scanner to miss hits.