Looking for some advice on what to do next when it comes to improving my
expedition type set up.
Background:
I picked up my Technician and General license at Dayton in 2015. Last fall I
decided to combine my love of off roading (rock crawling) with amateur radio
and take part in the January VHF/UHF contest. I decided to enter the FM only
category since it does not require a high level of sophistication or a huge
investment in equipment. Living in Northern Virginia I am near several large
population centers. Since FM range is LOS dependent and altitude is king I
felt I might just have a big advantage in setting up my Jeep Cherokee to carry
my radio gear up to 4,000+ feet in the dead of winter to either of two
locations that would give me access to between 12-15 grid squares and hopefully
800-1200 points. The big snow fall put 6-8 foot drifts on the trails I needed
to use, I am OK with 3-4 feet but 6-8 feet just wasnt doable so I ended up in a
highly compromised location with mountain tops 1000' above me on 3 sides. I did
get a couple of 150+ mile FM contacts but I got totally sh
ut out of major population centers. As a result I got "smoked", around 100
QSO's but only 60 points worth of contest contacts. June, September and
especially next January beckon.
Current Set Up:
15 foot fold over mast mounted through roof that drops into a manual rotator
attached to the cargo floor of the Cherokee. Mast cross arm is 15 feet above
the roof, 23 feet above ground level. Cross arm support a Cushcraft A14810s
for 2 meters, a Cushcraft A44911S for 70cm and a Diamond X-30A omni. All
antenna cabling is LMR-400. Connectors are UHF. Cables run inside the mast
down into the vehicle. Radio is a Yaesu FT-8800 (50W 2M, 35W 70cm) that is
mast mounted inside the vehicle with the remote head on a work table for
logging (all manual). I was using a diplexer between the two Yagi's and a two
position switch to select between the Yagi's and omni. I have since deleted
the diplexer due to losses and run the cables to an Alpha Delta 4 position
switch. I am adding 220MHz using an older Kenwood radio (35W 1.25M) and
switching out the dual band monopole for a triband omni of higher gain. I will
probably modify the mast cross arm to add a 220MHz Yagi once I settle on a
design for the cross arm and antenna locations that dont have interfering
capture areas and decide if I want to phase in a second set of Yagi's. I have
spent quite a bit of time minimizing cable and connector losses (under a dB on
all bands from radio to antenna connector and minimizing VSWR which is 1.2 or
less at 144 & 220 and under 1.5 at 440.
Here is is link to some photo's of the set up if you are interested:
http://s49.photobucket.com/user/nosigma/library/XJ%20Radio%20Rig?sort=3&page=1
Questions:
Where should I go next for the next performance improvement for this FM only
system?
Phase a second Yagi at each band for 2-3 dB? Add an RX pre amp on each band
(if you cant hear them you cant work them)? Add a TX amplifier to get up to the
allowed 100W for 3-4 dB? If the answer is amps then should I mount them at the
antenna for minimum loss or are my losses low enough at under 1dB that its not
worth the extra set up hassle? If the answer is RX/TX amps can I get away
without having to run a sequencer? Am I missing something more basic, like the
radio or driving up to north eastern PA for the next contest? A KX3,
transverters and amplifiers are NOT in the budget, maybe someday but I want to
keep this as basic and as simple as possible for now.
Looking for some suggestions.
73
KM4KMU
John
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