Thread: VHF cable type?
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Brian Whatcott
 
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Default VHF cable type?

I took a look at some sample specs to get a feel for the losses.

RG8X 7-9 dB/100 ft @ 400MHz
RG8U 4 dB/100 ft @ 400 MHz

You likely won't be operating at 400 MHz, but I'll use these figures
all the same. (Lower Fx is less lossy)

And I'll suppose that, what with the connectors, the loss is 8dB
versus 4 dB
That's 4 more dB

8 dB means you lose about 84% of your transmitter power.
4 dB means you lose about 60% of your power

So do you want 40 or do you want 16 ??

Brian Whatcott Altus OK

On Sat, 17 Jan 2004 00:46:44 GMT, "Lew Hodgett"
wrote:


"Bruce" writes:
I have to replace the wiring in my 58' mast plus 20' to my radio; my
question is this. RG 8x vs RG 8U.


snip

RG8U and support it with a messenger cable.

The difference in cost gets lost in the wash.

I use 1/16" S/S cable and secure the RG8U to it with tie wraps every 2'-3'.

If you don't support it, it will stretch and the impedance will change or so
I was told by a radio guru I trust.

HTH