In article ,
Jeff wrote:

All things being equal..what is the difference between a 3 mile rated
frs/GMRS and 6 mile GRS/GMRSrated 2 way radio when both employ 500mw power?

Impossible to say accurately without actually studying the two radios.

There may actually be significant differences in performance. Or,
there may be no significant difference in performance, and the only
distinction between the "3 mile" and "6 mile" radios was the amount of
nitrous that the marketing/advertising people were huffing when they
designed the packaging materials.

Does the fact that one is a tiny bigger, an inch longer on the antenna, 4
AAA batteries instead of 3AAA make one better than the other

Possibly. Possibly not. All else being equal, a radio with more (or
heftier) batteries may have a longer useful run time than a similar
radio with fewer/smaller batteries of the same type. I tend to prefer
AA-cell radios over AAA-cell for this reason, although the AA-cell
type are becoming harder and harder to find.

or is 500MW
Just 500MW

To a first approximation, radios with similar transmit power, and
similar receiver sensitivities, and similar antenna designs would be
expected to deliver similar range.

Without actually testing the two models of radio under somewhat-
controlled conditions, and/or tearing them apart, there's no way to
know for sure whether there are significant performance differences.

The thing to remember is that FRS was set up to be a short-range radio
system - the power limit on transmission, and the requirement that the
antennas have no directional gain (above that of a halfwave dipole)
and be non-detachable make it clear that the FCC did not intend FRS to
be a long-distance radio system.

I've only ever seen one FRS radio whose performance was markedly worse
than any other's. It's a cheap little "wear around the neck" model
whose antenna barely protrudes from the case at all... and I suspect
that the short and obstructed antenna is probably the cause of its
poorer range.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
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