VHF interference

[2nd_apprentice]

Can you mount a vhf aerial in close proximity to a wind generator or would it be likely to cause reception problems?

 

[SimonFa]

I wouldn't recommend it. The level of interference will depend on how good the receiver is and how badly the wind generator has been designed. RF Interference is a strange thing its not just about the frequency of operation but also something called intermodulation products. (Don't ask unless you has a background in maths and electronics or are really nerdy).

There will also be some shadowing (reduced coverage) caused by the metal in the wind generator which will reduce the coverage behind the generator.

The best place for your aerial is as high as possible a clear view in all directions.

 

[VicS]

(Don't ask unless you has a background in maths and electronics or are really nerdy).

but there is a simple explanation .. with a bit of schoolboy maths ... in Wikipedia. Unfortunately I am no longer a schoolboy.

 

[2nd_apprentice]

Yeah well, maths was never my strong side really
Shame about that. My aerial is mounted on the pushpit and having just ordered a 2m mounting kit for the Rutland I thought I could have something welded onto that. Probably a daft idea!

 

[William_H]

Yeah well, maths was never my strong side really
Shame about that. My aerial is mounted on the pushpit and having just ordered a 2m mounting kit for the Rutland I thought I could have something welded onto that. Probably a daft idea!

No not really. The advantage of aerial up that much higher would be worth the effort. Most I think wind generators use 3 phase pick up windings and a rectifier in the control box. Or possibly rectifiers in the generator. either way it is unliukely IMHO that interference will be a problem. However if you leave the antenna on the rail it may well be shielded in transmit by the post and turbine. good luck olewill

 

[RIBW]

No not really. The advantage of aerial up that much higher would be worth the effort. Most I think wind generators use 3 phase pick up windings and a rectifier in the control box. Or possibly rectifiers in the generator. either way it is unliukely IMHO that interference will be a problem. However if you leave the antenna on the rail it may well be shielded in transmit by the post and turbine. good luck olewill

I mostly agree with William but I had assumed that your current VHF antenna position was on the opposite quarter to the Rutland mast. If that is the case then "if it aint broke, don't fix it" applies (It will, most likely, be far enough away to be little impacted by the additional metalwork). If the current position will be under the Rutland mast then you will have to move the antenna. Raising it to the level of the Rutland seems like a good thing to do (for height/horizon reasons) but all that metal less than a wavelength away in the horizontal plane is best avoided as it will most likely modify the radiation pattern of the antenna. This will mean on certain bearings you will have excellent/improved reception and transmission and on others you may have nulls and you won't know which/when. (I spent my early working days designing and testing 'omnidirectional' VHF antennas for satellites). I am currently struggling with highly variable AIS reception. I think it is because the previous owner sited the AIS antenna 50cm aft of the Rutland.

Separating the electrical interference issue, if you suspect that the Rutland is the cause of noise it can be simply checked by applying the brake and restraining the blades, but it is unlikely to be a problem IMHO.

Best Wishes
Bob

 

[FullCircle]

I have a 0.5m Pacific RIB antenna (for AIS) on the pushpit right next to my Rutland 913 on the 2m pole. I also have the Navtex antenna right next to it. Both are withing the bracing tirangle of 25mm stainless struts.
I see AIS targets out to 20 miles. I also tried the antenna as an emergency back up to my VHF. Radio check with coastguard was loud and clear.

But.... it depends. It is possible that you MAY experience problems with your installation. If you do, consider moving antenna along pushpit, as small relocation can make a big difference.

 

[2nd_apprentice]

Problem is, it's a double ender so not a lot of room on the stern. At present the aerial would be half a metre from the Rutland mast.
Hence my idea of having a bracket welded on:

(Not to scale)

 

[Salty John]

That arrangement should work fine.