Radio interference , any advice ??

Can't help, but interested in the response as I feel my panels interfere with my 80 Channel UHF.

Cheers, Baz - The Landy

It will be the regulator. The new ones pulse and the rate at which they pulse causes radio interference. This has been a long term problem at mountain top radio installations. If your lucky your regulator can be set to have a fixed slow pulse and it will just give an occassional click on the radio. Check the handbook for the regulator. For best charging the fast variable rate is best so when not listening to the radio you can set it back. The other problem is that some of the regulators can cause the float level to rise above the safe working voltage of some radios.

I was told by an "expert" that one of the things that cause interference with home Solar installations is that the feed in cable to the regulator should be in twisted pair configuration as this cuts down the RF interference.

I just wish that all the ones around my house had done that as I cannot listen to AM any more in my street.
It may be the same for a car installation so it would probably not hurt to put your wire in a drill and let her rip.
Regards Philip A

I had exactly same problem Tim, but because my panel capacity was less than the load I was able to remove the regulator and solve the problem without fear of overcharging the batteries, probably not a solution for you. RFI shielding and suppression is not an easy task. An option if you wish to retain some form of regulation is to steer clear of MPT or PWM regs and find a linear regulator, cheap and not very efficient compared to the former, all depends how keen you are to hear AM stations, but then life is full of compromises .Is also possible that some regulators do not cause interference, it`s called 'Chinese choice'.

Leigh.

It will be the MMPT regulator. Any solution is going to cost you, either replace the regulator or modify the system.

To modify things, you need some large ferrite rings which you can salvage from old computer power supplies - the rings will look like these http://media.digikey.com/photos/Panasonic%20Photos/KR16TT251508.jpg
have to be big enough to wrap a few turns of the power cables into like this - http://www.brats-qth.org/training/graphics/filter2.jpg
Preferably both the +ve and -ve should be wrapped in together but, depending on your cabling, that may require a huge ferrite. Splitting the + & - between 2 rings is likely ok just not as good.
Something like 4 or 5 turns should suffice with the ferrite located close to the regulator. The idea is that the ferrite chokes off the spike energy before it can be transmitted via the battery cabling. Some of this is transferred through the power cable to the target but a lot is radiated by radio waves so will be getting into other peoples gear as well.

If you have any of this style ferrite lying around - http://www.mds975.co.uk/Images/amateur_radio/ferrite_ring_clip-on-ferrite.jpg then you can clip them onto the battery leads closer to the vehicle. These are often supplied with computer monitors and often just clip on.

If you still have the noise then surgery is required and you need include some small capacitors. Small 100pf units should do and simply connect between the + & - wires. You want one at the output of the regulator plus maybe an additional one at the affected radios as close to the radio as possible (might have to cut the wires to fit). They will have little effect if placed down the power cables away from the units.

That should have killed it off but there's no guarantees with RF. It can take a lot of trial and error but teh above is pretty simple to try out.

Thankyou for the replies , have tried 2 x small clip on ferrites

No change but will try the larger ferrite rings you suggest.