|
Sent: Tuesday,
March 28, 2006 13:53 Subject:
Articles For Frequently Asked Questions, Page #1 What make of ham radios do you install on the MARC members
motorcycles when doing installations for them? 90% of us down here are running the Kenwood TM-742A or the
Kenwood TM-D700A. The 742 can be made into a Tri-Bander by adding another
module, but the Kenwood TM-742A is no longer available, so now all the newbees
are adding the TM-D700A. Both are Base/Mobile radios. Almost 100% of us are
running the Comet HP-32 antenna for local communications, because it was
designed by the company that makes all the Comet antennas, specifically for use
on motorcycles. While the owner of the manufacturing company was here in CA at
NCG, they called me up and I took the, then, 1996 Gold Wing up to the warehouse
and demonstrated why we were breaking so many antennas on motorcycle. Now that
company and NCG have redesigned all there basic antennas to survive on a
motorcycle. Every time NCG gets a new antenna, they give it to me, I test the
SWR (Standing Wave Ratio), gain, Field test strength, Direction of signal from
horizontal, Pattern, etc., to run for a summer, always about 40,000
to 50,000 miles to test them before they put an order in for them. If it lasts
the summer on the back of the rack and it meets their criteria for the other
specs, they then order them.
That's probably the setup I'll go with unless you have some other
recommendations. What kind of mount do you use for the Comet? We have the antenna brackets here at the house
that clamp onto the 1/2 inch tubular trunk racks, see our MARC Web Site at
<www.marc-hq.org>
for pictures of all brackets we have available to our members. We also have the
flat rack mounts.
I was
thinking of using some kind of stock CB antenna base to mach the other two.
Well we used to try that, but it
didn't work out. First of all some of our members were putting then on a stock
Honda bracket like the CB or AM/FM antenna brackets, but the output from that
location was too directional and you could only transmit to one side of the
motorcycle. Other tried to slant the antennas to match the rearward slant of the
other 2 antennas, but they the signal was going up in the air to the front of
the bike and bouncing off the pavement to the rear. Of course they both worked
if they were close to a repeater site or another motorcycle, but once you got
out into a gray area, they lost contact while the rest of us were still
communicating. We didn't learn this stuff over night, we have been testing
antennas with field strength meters and other devices and experience for over 12
years.
I also put a cover on
my bike most of the time, so folding over and out of the way of the cover would
be important. Not a problem, darn
near all Comet antennas are fold over antennas. At least all the ones we use are
fold over antennas for the same reason. However, Comet does have some of the
cheaper antennas that do not fold over, but they are also the ones that are
breaking after a few thousand miles. So we tested them, but found them
unsuitable for use on a motorcycle.
So you say you'll be running two hams on the bike?
Yes, one is the Kenwood TM742A that
I have had on the 5 Gold Wings since we started MARC back in 1992. Now I am
going to mount the Kenwood TM-D700A to work in conjunction with my Garmin Street
Pilot lll Deluxe that is already on the bike, just for use with the APRS
(Automatic Position Reporting System> so that I can be tracked all summer and
for our many MARC Charity and community service events that we provide
motorcycle mobile communications & traffic control for. We now have at least
8 MARC members here in the Southern CA area that have APRS. I also bought a
Kenwood TH-D7A hand held for use at home for APRS. That was $850 that I spent
for radios in January. Hope it all works, but I have some real experts on this
stuff in our club, so I don't have to worry about learning how it all works.
Couldn't both aprs and
voice be accomplished with the 700? Yes, the Kenwood TM-D700A could do both, but I also want the 220 module
in the Kenwood TM-742A to be available to use on the free Condor System of
repeaters hear in CA. So I am leaving the 742 on board and adding the D700A for
APRS. The 742 will not work with the Garmin SP lll for APRS use.
I think that's the radio
I'll end up with. Do you have separate ptt switches for each? Yes, see MARC Web Site for our Waterproof PTT
buttons and the custom make brackets that fit right where your left thumb is
when riding.
I've got an
FRS radio integrated into the OEM ptt, and I'd like to use the oem switch for
all three if its possible. It
may be possible, I don't know. Our BA-MARC members in the San Jose/San Francisco
area all integrate their systems, but only few of us do it down here because we
work some of our charity events with GWRRA members who only have CB, so we have
to be able to hear both CB and Ham radio at the same time and send both at the
same time without using a switch to go back and forth.
I think I'll call Kennedy in the morning
and see what he has to say. Say hi to Jon at Kennedy for me. We actually visited him at his home back
in KS when we were in his home town 2 summers ago, and MARC members have done a
lot of business with him. THE END, RAY
|