A few questions about those WALKIE-TALKIE like radios....?

These all use the same service (FRS). You can mix and match between manufacturers. Some special features, like "distinctive ring" type paging, might not work exactly the same between units, but the basic push-button-and-talk stuff will work fine.

If they are on either CB (the Citizens' Band) or the Family Radio Service (FRS), then yes. Just get them all on the same channel. Check the particulars of each individual make and model to see what channels they have. (FRS channels are separate from CB channels.)

Bear in mind also that the range is often MUCH, MUCH LESS than the advertised maximum. These aren't cell phones. They don't work through a central repeater or tower. They have to be able to communicate directly with each other, even when both are down in valleys or inside buildings, and that's much harder. The reason cell phones work so well is that one end of the communication link is always high up on a tower with nothing blocking it.

I have gotten near 10 miles on FRS. The record is about 160 miles. Between mountains reception is good. Any land or obstruction greatly reduces transmission. Bubble pack radios are frowned upon, especially GMRS/FRS types. GMRS requires a license, about $75. Channels 1-7 share FRS/GMRS, 8-14 FRS only, upper channels are GMRS only. GMRS is NOT for business. FRS was made for family use only, which includes family business.

For more information see Personal WirelessForum........................

greg

Based on ham radio experience, I would assume you could get 2000 miles if one of the transmitters were in a spacecraft, talking to the earth's surface in a straight line.

Getting through buildings and trees and around the curvature of the earth is the hard part!