New to the CB Radio....need help!

How far they can reach is not a question that has a straightforward answer. it depends on an infinite number of variables.

For a radio you can just hook up, turn on and go with good performance right out of the box, at the present time, you will be hard-pressed to beat the Uniden 980SSB.

If height is not of concern, for the mobiles, an MFJ 1966 whip (108" steel whip) mounted at center of largest available mass (generally the middle of the roof) is the best mobile antenna setup you can run. if height is a concern, go for the Sirio Performer 5000.

 

Handheld CBs have limited range because they lack proper antennas for the frequency. If you're wanting to equip your people with HTs, you'd be better off going to a serious UHF business band station with a tower and a repeater mounted at your base location. A system like that would extend your range to perhaps a 20-25 mile radius. Base to mobile (vehicle mounted) CB should be good for the 6-mile distance but reliable communication from one edge of the 12-mile diameter to the other may be spotty, depending on terrain and quality of the antenna installations in the vehicles.

 

I would recommend getting a hold of a company that specializes in business communications to see if low band (HF near the cb band) or low-band VHF radios are better for you than Mid-band vhf or UHF radio setup. I remember reading somewhere that out in Montana they had low-band VHF with no issues of distances and the costs were really reasonable and the quality of the equipment was better than cb.

 

Low band would probably work pretty well out there if you can still find gear at a reasonable price. Back in the 60-70s most Iowa county SO's covered their entire county on 37.10 or 37.14, but migrated to mid-band VHF to allow handhelds with a repeater. Now everything is moving up to 700-800Mhz which means there might be some of the lower freq stuff available on the used market at reasonable prices. Not much inexpensive new low band gear that I've seen recently. In '67 the ISP covered their entire districts with 100w GE and Motorola mobiles and a base station on 42.58, but the base ran 5kw and was on a 350ft tower!