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February 2006 MONITORING TIMES 69

ith the wide selection of FRS

(Family Radio Service) walkie-

talkies available from virtually

every electronics shop, mass merchandiser,

and Internet electronics site, there’s no ques-

tion that these little radios have captured the

imagination of our technical generation. It’s

reassuring to be able to keep in touch while

caravanning, hiking in the woods, hamfest-

ing, and other temporary separations. How

does the casual consumer decide among the

bewildering array?

And what about MURS (Multi-Use

Radio Service)? Is there really a difference

between it and FRS from a performance

standpoint? After all, the advertising rates the

radios by talking distance, ranging typically

from two to eight or more miles.

❖ Created Almost Equal

Is it possible that a $19.95 pair used

under the same conditions as a $79.95 pair

can achieve the same results? Since all FRS

radios are limited by law to no more than 1/2

watt of output power and they all have at least

14 UHF channels (462/467MHz band), there

must be some subtle differences

that let one model beat another.

For starters, some have lon-

ger antennas (FRS antennas are

permanent; you can’t substitute

a longer antenna!), and the most

expensive of them (those with the

greatest distance claims) include

eight additional channels for the

FCC-license-required GMRS

(General Mobile Radio Service),

thus offering higher power (2

watts). Many FRS/GMRS radios

also have features like drop-in

chargers, voice activation (VOX),

calling tones, and sub-audible

tone squelch to reduce co-channel

interference.

But what about that other, no-

license-required, service? MURS

allows higher power (2 watts)

on five preset VHF (150 MHz

range) channels. Base/mobile

and hand-held transceivers are

available at very reasonable cost

from communications equipment

suppliers. Unlike FRS, antennas

are interchangeable, permitting

the connection of mobile and roof-

top or tower tower-mounted base

antennas for extended range.

But back to the basics: Is

there an inherent advantage in us-

ing one FRS hand-held radio over another?

How does FRS compare with MURS under

the same conditions?

❖ Our Units

Our choices for the test included a pair of

Cherokee FR-465 FRS radios (discontinued),

operating at 0.5 watts and with removable

whips (disallowed by the FCC, but allowing

antenna swapping); a pair of Midland G-225

FRS (claiming a 7 mile maximum range by

switching from 0.5 watts FRS to 2 watts with

GMRS channels); and a pair of Alinco DJ-

196 2 meter held-helds at 0.8 or 4 watts with

removable antennas). We used the Alincos on

148 MHz, close enough to 151.820 MURS

channel 1 for a valid simulation.

As readily seen in the accompanying

photo, the UHF Midland units have a short

stub antenna, the UHF Cherokees have much

longer antennas, and the VHF Alincos carry

the longest of all. With all other factors be-

ing equal, the longer antenna means greater

aperture (signal capture area). Will that make

a difference?

❖

Our Field Test

To compare the relative performances of

the three radios, one was operated from in-

side a house while the other unit was carried

through the woods in mountainous terrain.

This would allow three basic parameters to

be tested: operation from inside a building,

attenuation from foliage, and blocking by

terrain. Additionally, it was a foggy day,

slightly worsening line-of-sight attenua-

tion.

At a distance of about 1/4 mile into the

woods, the Midland was solid copy, but ac-

companied by background hiss; the Chero-

kee and Alinco were noticeably stronger.

At 1/2 mile, with more intervening

hills and trees, the differences were more

pronounced: The Midland was erratic in

performance, while the Cherokee and Alinco

remained stronger and consistent. But at a

mile, with even more rolling terrain, both the

Midland and Cherokee were unreadable. The

Midland became readable when switched

to high power (2 watts), while the Alinco

remained loud and clear on low power (0.8

watts).

At 1 mile away, with con-

siderable intervening terrain and

woods, only the Alinco was read-

able by switching to high power (4

watts). Changing antennas seemed

to make very little difference in

communicability between the

UHF or VHF radios. It would be

expected, however, that under dif-

ficult fringe-reception conditions,

a longer, gain-type antenna should

make a difference.

❖ The Bottom Line

The tests seem to confirm

theory – and probably many read-

ers’ suspicions: The higher the fre-

quency, the worse the attenuation

by foliage and intervening terrain;

and while stub antennas may work

for short distances, they degrade

badly on the long haul.

If price is a necessary consid-

eration when you’re buying hand-

held transceivers, select a pair of

FRS transceivers with the longest

antennas; next, consider the ability

to switch to higher power (which

requires the easily-obtainable

GMRS license). If price isn’t a lim-

iting factor, buy MURS units for

considerably better performance.

FRS or MURS? Hype or Hot Performance?

By Bob Grove W8JHD

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