Replacing VHF antenna, uses RG5 cable?

[Mary-Bill]

We need to replace out VHF antenna which is mounted on the arch of our 2008 Mariner. We purchased a new one from West Marine and went to install it and had problems with the connections. Looks like they used RG5 cable and the new antenna uses RG8. Is there any way to connect them or do we have to run the RG8 cable back to the radio which will require fishing the new wire through the arch and much of the superstructure. All of the current wires in the arch seem to be bundled together so we cannot attach the new wire to the old one to pull it through. We were really surprised to see RG5 cable used instead of RG8. Everything I see online says RG5 is for in home use. Also what do we lose using the RG5 instead of RG8? Is there appreciable loss of gain over the 30 foot run? Thanks in advance for any info.

[km1125]

I don't think you'll see any appreciable difference in loss at a 30' length.

Your bigger concern is putting a splice near the antenna. While it "CAN" be done, doing it so it's virtually transparent to the transmitter is the bigger issue. If there's any reflection in the signal it will reduce your effective transmitting power. If the cable provided with the antenna is long enough to make the run in one piece, then I'd suffer through fishing the new wire from one end to the other.

Also, having an extra connection in the system introduces yet another point of failure that you'd rather avoid.

[bud37]

Welcome to the forum.......have you considered just installing a new antenna in a different spot closer to the helm , maybe easy cable run. Just decommission the original.
On ours there is access behind the panels on the arch base......not sure of your model though.