Coax type help please ?.....

fires999

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Nov 16, 2014
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Hertfordshire, UK
Good Morning Forum,
Just a quick coax question that I'm sure many of you can answer, so here goes...
What is the best coax to use for the freq range 220- 380 mhz ?
Hopefully I can use the N type connectors I have and please excuse my ignorance but does the mode AM or FM make any difference? If it does I will be listening in AM mode and receive only, no transmit.
Thankyou in advance as always, have a great weekend,
Kevin ( US Airforce in Europe Fire Dept, Suffolk, England)
 

chief21

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The type of coax depends on the necessary length and the impedance of your radio. The type of coax connectors depend on the type of connector on the radio and the antenna. Most radios require 50 ohm coax. If the run is relatively short (less than 50'), you could probably get away with RG8 or even mini-8. If the run is longer, you might need to use a lower-loss coax, like LMR400 or similar. If you google coax loss chart, you can determine the loss in different types of coax. Less loss = more signal.
 

fires999

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Nov 16, 2014
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Hertfordshire, UK
Morning,
Thankyou for quick reply!
So coax length will be really short as suggested, no more than 20' .
Connectors I have are N type or pl259.
Thanks again,
Kevin
 

mmckenna

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Morning,
Thankyou for quick reply!
So coax length will be really short as suggested, no more than 20' .
Connectors I have are N type or pl259.
Thanks again,
Kevin

RG-58 would be fine. I run that for our 800MHz mobiles, including a few buses where I had to buy NMO mounts with 25 foot cables.

RG-8x would be fine.

LMR-195, LMR-200, all good cables.

Be careful going too large, as the larger cable will easily snap the antenna connectors off radios if careful strain relief isn't done. If using a larger cable, you'd want a short flexible cable to make the connection. That, and the extra connectors will add to the loss, negating the benefit of the larger cable on such a short run.

You should have no issues finding N connectors for any of those cables.
 

fires999

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Nov 16, 2014
Messages
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Location
Hertfordshire, UK
Evening from the UK,
Thanks to everyone who took the time to read and especially those who replied.
Really appreciate the advice - also the way your answers are educational, easy to understand without being patronising..some forums love it when you know little about a subject and treat you like a 8 year old !!!
So thanks again so much, have ordered suggested bits from local radio shop...will let you know how I get on.
Kev ( USAF Mildenhall Fire Department, Suffolk, UK)
 
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