LARC
ARES Simplex Tests |
This Simplex test operated differently than previous tests. Usually, all the participants do test
transmissions, and everyone does a signal report on everyone else. However, in the latest test, only
a couple of drivers with mobile radios did test transmissions. They started with each doing a test
transmission at a central location, and then they drove 4 km away from the center of the city before
doing their next test. We planned on having 4 drivers, going North, East, South and West in 4 km
stages. However, only 2 drivers were available, so we did East and West.
As soon as one of
the drivers finished his transmission, he started driving to his next location. While he was
driving, we got back on the VE3GYQ repeater, and gathered basic signal reports from all participants. By
basic I mean one of three assessments: Nothing heard, Weak signal, or Strong signal. Then we'd do
the same process with the second driver. By the time he was finished, the original driver was close
to, or at his next location, so there wasn't much waiting while drivers were in transit.
Our test simplex frequency was 147.57 MHz, the same as the fallback ARES simplex frequency.
However, this is at the high end of the 2 meter band, and most antennas are optimized for the center
of the band. In the future, we'll probably use 145.350, the transmit frequency of the VE3GYQ
repeater, by having the mobile operators tune to the repeater, but press their reverse button for
test transmissions. Having everyone always on the repeater frequencies will greatly simplify the
process, and probably speed it up. (for reference, here's the 2 meter band plan)
We planned to
stop when no one could hear the test transmissions any more (or when a driver encountered an ocean).
However, we had participants who were a long ways East and West of the city, and they continued to
receive strong signals as the drivers were close to them. The end actually came when we started having
problems with the drivers being able to reach GYQ for coordination purposes, and we declared
completion when they were 20/24 km out.
To answer the inevitable question "So, how did it
go?" I have 3 groups of information: