Thought a few folks might find my test results informative.
Antennas are mounted in the attic above my garage. Radios are off the shelf with the only modifications is the receiving GMRS/FRS/VHF units have the "Rubber Ducky" antenna removed to use the attic antennas. Garage is within a wooded area, topographically the area is almost flat +- 100 feet.
I used a Voice Activated (VOX) recorder in my communication shack to allow for one-person (me) testing. GMRS, FRS and VHF radios on both ends are hand held. The CB SB mobile antenna is mounted six feet off the ground with a metal ground plane (Kawasaki Mule aluminum roof).
Total distance tested (as the crow flies) was 4.51 miles. Weather was sunny and warm.
I drove the Mule south, stopping at landmarks and addresses. I would radio back to the VOX recorder giving my location in a non-discernible code. On location I would down what "code" was used for which location. Example; "I'm not too far from home" meant I was across from a cell tower. I would use the same code across the four different radio platforms mentioning a number designator for each platform.
#1 = GMRS
#2 = FRS
#3 = VHF
#4 = CB SB
In my communications shack I have a wall mounted topographic map of the area. Home location is marked with a small brass nail. Listening to the recorded messages I was able to ascertain distances. I drew different colored circles around the home location representing the test results below. Circles give the communications operator a idea of what they can expect.
VHF 4 watts. Last clear communication was at .87 miles. I expected VHF to do better (no repeater).
FRS 1/2 Watt. Last clear communication was at 1.02 miles
GMRS 5 watt. Last clear communication was at 2.98 miles
CB SB 12 watts. Last clear communication was at 4 miles
I want to repeat my test going north, east and west but haven't allocated the time to do so.
Antennas are mounted in the attic above my garage. Radios are off the shelf with the only modifications is the receiving GMRS/FRS/VHF units have the "Rubber Ducky" antenna removed to use the attic antennas. Garage is within a wooded area, topographically the area is almost flat +- 100 feet.
I used a Voice Activated (VOX) recorder in my communication shack to allow for one-person (me) testing. GMRS, FRS and VHF radios on both ends are hand held. The CB SB mobile antenna is mounted six feet off the ground with a metal ground plane (Kawasaki Mule aluminum roof).
Total distance tested (as the crow flies) was 4.51 miles. Weather was sunny and warm.
I drove the Mule south, stopping at landmarks and addresses. I would radio back to the VOX recorder giving my location in a non-discernible code. On location I would down what "code" was used for which location. Example; "I'm not too far from home" meant I was across from a cell tower. I would use the same code across the four different radio platforms mentioning a number designator for each platform.
#1 = GMRS
#2 = FRS
#3 = VHF
#4 = CB SB
In my communications shack I have a wall mounted topographic map of the area. Home location is marked with a small brass nail. Listening to the recorded messages I was able to ascertain distances. I drew different colored circles around the home location representing the test results below. Circles give the communications operator a idea of what they can expect.
VHF 4 watts. Last clear communication was at .87 miles. I expected VHF to do better (no repeater).
FRS 1/2 Watt. Last clear communication was at 1.02 miles
GMRS 5 watt. Last clear communication was at 2.98 miles
CB SB 12 watts. Last clear communication was at 4 miles
I want to repeat my test going north, east and west but haven't allocated the time to do so.
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