Advice on VHF Cable

[OceanSprint]

Following advice here on my mast head VHF aerial i am renewing the wiring up the mast.

I bought 15 m of Banten RG58 Low Noise coax cable .... See

http://www.ebay.co.uk/itm/Banten-RG...UK_Sporting_Goods_Sailing&hash=item4ac0c00182

But the old wire is about 10mm diameter, and the new wire about half that, 4 or 5 mm.

Have i bought the right stuff?

If not, what do I need?

It is for an ICOM DSC vhf set.

Thanks

 

[nigelmercier]

You may not notice a difference, but RG8 (as you had before) would be better.

 

[grumpy_o_g]

RG58 is 50 Ohm impedance cable so it should be absolutely fine - it's the right product as long as your VHF set is 50 Ohm impedance which I would think it most likely is, especially if it's not too old. The manual will tell you the impedance of your VHF set if you want to be absolutely certain.

 

[lenseman]

You may not notice a difference, but RG8 (as you had before) would be better.

How do you know? It might have been RG213 or even H100; but you correctly stated that it will be superior to the RG58 (RG58U).



.

 

[William_H]

RG8 the large coaxial cable has less loss of power. At VHF frequencies you could loose a third of your power 25w in the cable at a length a 15 metres compared to what you have bought. Don't be dismayed however. The actual loss in performance will not be noticeable. Use what you have bought. Only the pedants would worry about the losses.
I do wonder if the old cable is really bad. The larger cable might tend to be more resistant to damage etc. But if the copper is corroded and can't' be trimmed back to clean copper then it has to go.
good luck olewill

 

[nigelmercier]

How do you know? It might have been RG213 or even H100; but you correctly stated that it will be superior to the RG58 (RG58U).

OK, it was a guess. RG213 is also likely, possibly more so.

 

[Salty John]

RG58 is quite lossy, about 5db in a 30m run. 3db loss is a halving of the signal power. 15m of RG58 is on the fringe of acceptability for we pedants but it'll probably be fine in the real world.
Here's some thoughts on marine coax: http://saltyjohn.blogspot.co.uk/2013/06/marine-coaxial-cable.html