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Lightning conductor for ametuer radio antenna mast - electrician says regular PVC sheated yellow green wire is ok from mast to earth rod

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As per title I am getting a corner of my house setup as a radio shack and wanted to protect it appropriately.

The antenna is made of fibre glass but sits on an aluminium pole that brings the total height to 10m tall (only house in the area).


We have agreed to setup an earth rod below the antenna mast and earth it but the question is - will regular 35mm green/yellow sheated earth be good enough to provide earthing for antenna mast while being exposed to the elements? How long will it last?


Any thoughts on the electrical setup for the radio? We are planning to use the same earth rod and make a TT island for the power socket that feeds the radio unit (as main electrics is PME). The radio will be fed electric connection through an MCB by taking power from the main distribution box protected by a Type 1/2/3 SPD (I have 3 phase 100A supply from DNO) and we will use the earth rod for earth supply.


The radio unit will be powered by a seperate consumer unit which gets it's earth supply from the rod (I might also get a Type 1 SPD in the TT island consumer box).


The antenna and the TT island powering the radio will be linked by a 700A rated earth bar enclosed outside the property in an IP65 enclosure.


Appreciate any thoughts on my setup.
Am I being overkill and do not need a TT island for my radio setup? Will earthing the antenna be sufficient?
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  • 0
    Is this a VHF radio? Your post suggests a sleeved dipole or similar aerial type, enclosed in a fibreglass cover, which is common. It would be unwise to have any other metalwork near such an antenna because it will make a complete mess of it omni characteristic, which is probably why you chose it over a beam in any case. The chance of a lightning hit is really quite remote and anyway may well demolish your house, and as Mike suggested just earthing the pole by its base in the soil will al least take away some of the effects of nearby flashes. If it is a coax fed vertical, the coax outer is probably not connected to the support pole, it is worth checking. The best lightning protection you can get is probably a spike fixed to another pole some way from the antenna, with a good long earth spike connected. It does not need a large cable, it is not going to get hit, just reduce the local electric  field strength to your antenna.


    I have had many antennas on top of big hills for contests, and despite some thunder storms never had anything broken. No direct hits either, although the Landrover was almost blown over on top a Welsh summit once, which was interesting to say the least. Estimated windspeed was 140MPH at the time and the mast guys were very tight with a big beam at the top.


    73 de G8FNR
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  • 0
    Is this a VHF radio? Your post suggests a sleeved dipole or similar aerial type, enclosed in a fibreglass cover, which is common. It would be unwise to have any other metalwork near such an antenna because it will make a complete mess of it omni characteristic, which is probably why you chose it over a beam in any case. The chance of a lightning hit is really quite remote and anyway may well demolish your house, and as Mike suggested just earthing the pole by its base in the soil will al least take away some of the effects of nearby flashes. If it is a coax fed vertical, the coax outer is probably not connected to the support pole, it is worth checking. The best lightning protection you can get is probably a spike fixed to another pole some way from the antenna, with a good long earth spike connected. It does not need a large cable, it is not going to get hit, just reduce the local electric  field strength to your antenna.


    I have had many antennas on top of big hills for contests, and despite some thunder storms never had anything broken. No direct hits either, although the Landrover was almost blown over on top a Welsh summit once, which was interesting to say the least. Estimated windspeed was 140MPH at the time and the mast guys were very tight with a big beam at the top.


    73 de G8FNR
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