Here is a better way than driving around with your friends and guessing about antennas.
http://www.mfjenterprises.com/Product.php?productid=MFJ-5005
That'd be a neat tool to have if I had $450 to burn.
I don't have a Ham Radio license, but have heard these A wipes doing that and really I would love to see them gone. It could be affordable for the Ham club in your local area to buy as a group.
http://www.mfjenterprises.com/Product.php?productid=MFJ-1026
Could this be the answer to the noise interference on AM?
Mark
I wonder how good this actually works. It works on some sort of phase shifting from what I see.
i cant justify that kind of money unless i know it actually works good. i have a real bad buzz right across a local 50kW (KOA 850) which is also suppose to be my LP-2 for EAS but it is unusable the last few months but i doubt even if it does work that it could cure the kind of interference i'm dealing with here. luckily it seems to die off the higher up the band i go being barely audible at my 1630 frequency.
This technology became available to ham operators in the late '70s. It works by using several vertical whip antennas arranged in a circle. The antenna is electronically rotated to simulate a mechanically rotated antenna. As the antenna is approaching a signal source the RF frequency is higher due to Doppler shift and as it is receding the signal is lower frequency. This produces an audio tone in an FM receiver and the tone zero crossing indicates the antenna array is broadside to the incoming signal or on peaks, is pointing at the source.
Since this depends on the physical dimensions of the array being comparable to a wavelength it is very unlikely to work at AM BCB frequencies.
@Radio8z i know the Doppler DF'ing unit is proven technology (and well worth every bit of that $450.00) and works quite well. i was referring to the noise filtering unit in post #5.
I own the noise canceling device. It works quite well.