Motorola PR860 HF question

[lbredefe]

Hi Everyone, this is my first post. Everyone here seems pretty nice and after reading around a bit, I have what i think might be an odd, multifaceted question...

I bought a slew of PR860's from a police auction some time back, they were commonly used in the early 2000's and i assume late 90's, they are HF with the longer more rigid antenna (~14") and i have programmed them for an LMRS (29.x mhz) frequency for which i am pursuing a license.

my question is this...... the range, even on 6 watt high power mode, seems to be limited to less than a mile with trees on flat ground, and about 2.5 miles on water, BASED on this experience, how were these ever useful for police operating in a 20 mile radius? how could they even hit a (i presume) repeater if it is located more than a mile or two away?

did their cruiser radios act as repeaters? if so, is anyone familiar with a vehicle based repeater radio model that was commonly used with LE in the USA?

I am really trying to understand what hardware piece of the puzzle i am missing, these radios are indestructible, easily programmable, and i would like to buy the accompanying unit for the vehicle if that is the missing piece that adds some range. I'd like 10-15 miles range if I am within 1 mile of the vehicle while using one of these handhelds. I understand that the other person would need the same vehicle setup to be able to reach back to me.

 

[tweiss3]

I've had conversations with Spain and England at 5 watts on 10 meters (SSB). FM is a bit different, but yes, typically repeaters were used, and in a mountainous region, 6W can have decent range with appropriate infrastructure. In my area, 6 meters repeaters have huge footprints, and I have no issues getting in with a HT.

 

[mmckenna]

That's probably the NAB6064A antenna. New, they need to be cut to the frequency they are intended to be used on. If these are old radios and the frequency the police department used was not 29.xMHz, then the antennas are badly out of tune.

Also, low band portables are notorious for being poor performers due to the lack of counterpoise under the antenna. The radio body is just too small to act as the counterpoise. A user holding it in their hand can couple to the radio chassis and help a bit.

Mobile Extenders, the repeater that rides in the car, were usually used to extend range from a hand held radio using the vehicles mobile radio. But I don't think I've ever heard of anyone using low band as the portable and linking to the mobile that way. Usually it's a higher frequency portable radio linking to the low band radio in the car. Running a low band input/low band output as a mobile extender sounds like a real pain in the rear. The desense, antenna matching, etc. would make it difficult to get right.

 

[prcguy]

Two walki talkis talking to each other with antennas in the -20dB range and 6ft elevation is not so good but one walki talki talking to a large base antenna at 20 or 30ft elevation with 0dB gain is 20dB much better. Give it a try to a base station and I'll bet you can get 5mi range no problem and possibly more.