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[KF4WDD]

Do hams generally recommend RG-174 as the best choice to get the coax started from the antenna and into the car? I would like to connect a thinner coax to a connector, and then have a few feet of RG240UF go to the radio. Would I need a female-female barrel connector to make this work between the two different coax?

Thanks and 73.

[K5LXP]

RG-174 is a pretty poor choice for just about anything.  RG-316 would be "better" for a short jumper.  LMR240 is a bit more than twice as thick as 174 or 316 but still less than a quarter inch.  Just drill a quarter inch hole and save yourself the problem of sourcing cables, connectors and adapters.  All that extra plumbing ends up being is more cost and points of failure.

Mark K5LXP
Albuquerque, NM

[W9IQ]

There are two considerations regarding RG-174.

Electrically, there is about 0.2 dB matched loss per foot on 70 cm and about 0.11 dB matched loss per foot on 2 meters. The actual loss varies by the grade and manufacturer of the coax. So if you keep the length of the RG-174 relatively short, say 2 to 3 feet, the losses are not too bad if your SWR at the antenna is low.

Mechanically, RG-174 is very thin and more easily damaged from flexing and pinching forces. If you need to thread it through very small holes, then you need to put on your own connectors. Crimp style connectors, using the proper tools, are the only way to go on this cable as the center dielectric is easily melted from soldering.

- Glenn W9IQ

[KD6VXI]

Use Lmr240.

Then terminate the LMR240 with the dame connector Wilson uses on their antennas.  It's the dame size as thr Lmr240.  For the life of me I can't recall what that termination is called.....  Brain fart!  It's a mini UHF.

Then use a mini UHF to PL259 adapter and you are set.  One adapter, and one 3/8 inch hole!   I'd go to a half inch and use a grommet, but that's just the electrician in me.

--Shane
WP2ASS / ex KD6VXI

[WA3SKN]

What frequency(s) are you planning to use and what power levels are planned?

-Mike.

[KF4WDD]

I have an Icom 706MKIIG. I plan to use 100 watts HF, 50 watts VHF, and 35 watts UHF - max power as the radio allows.

[WA8NVW]

I have an Icom 706MKIIG. I plan to use 100 watts HF, 50 watts VHF, and 35 watts UHF - max power as the radio allows.

There are two separate antenna feedline connectors.  And you know that it's a long way between 1.8 MHz and 450 MHz.  No single mobile antenna will cover all the frequency bands in that radio.  So you'll need to do your antenna cable trick twice, routing to two separate antenna mounts in different locations.