[Elecraft] Mobile high power

[Edward R Cole]

I worked in the 2-way radio business for 30-years here in AK; did a 
lot of mobile installs.

Typical police/ambulance radios ran 110w MOT stuff.  Some commercial 
ran 25-50w with smaller footprint sized radios.  Nearly all is either 
high-band VHF 150-174 MHz) or UHF (450+).  All were wired with neg 
tied to the chassis.

However the local refuse company trash hauler trucks ran 42-MHz, and 
the state DOT still uses Low-Band VHF (47 MHz, I think).  A lot of 
commercial radio was going trunked and into 900-MHz band (in urban 
areas).  Low-band antennas were sensitive to good grounds (like HF ant are).

Makes sense that the "cop cars" would be special-made for comms 
(interesting to see the 150mph speedometers).  Most I installed in 
the 1990's were Crown-Vics; now they run Tauras' or other full-size 
sedans.  Quite a few SUV's and PU's in use, as well.

I had a 50w dual-band FM mobile with mag-mt whip on my 2002 Toyota 
Tundra and speed-control was sensitive to 2m transmissions (sped up 
about 5mph), but my 2015 F250 diesel seems immune to RFI.

I run the 50w dual-band, KX3 plus KXPA100 on HF/6m and 2m-SSB at 
150w.  12v power is run with two No. 8 wires from the left 
battery.  Neg. is bolted to engine chassis about six inch away from 
battery and normal battery neg cable used to engine.  Most of the 
equipment is turned on by a HD relay in the HD power cable with relay 
controlled from one of the front panel switches.  My truck has dual batteries.

details: http://www.kl7uw.com/Mobile.htm



73, Ed - KL7UW
   http://www.kl7uw.com
Dubus-NA Business mail:
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