oh i see why jon wineke gets so upset by my comments about paint cans enclosing antennas, he is a professional, does scanner software support, i assume he sells yagi antennas and if people are just enclosing the stock antenna with stuff around the house then why buy a yagi antenna? just guessing, that the only reason i can think of why they would get upset about me trying to help someone with simulcast distortion.
I don't sell antennas. I object to your recommendations because they will cause more problems than they solve for the majority of people who try them.
What you recommend only works in a very narrow set of circumstances, specifically when the strongest tower signal is significantly stronger than the other towers' signals, and enclosing the antenna in a paint can attenuates the signal just exactly enough that all but the strongest tower's signals are pushed below the noise level, so that the receiver can only detect the strongest tower's signal. It's a rare occurrence for the following reasons:
1. For your suggestion to work, there has to be a significant signal level difference between the strongest signal and the next strongest signal, but the power levels still have to be close enough together to cause distortion. If the signal power levels are too close together (e.g. less than 3dB), sticking the antenna in a paint can will attenuate them all into oblivion together. If the signal power levels are too far apart (e.g. more than 10dB), then simulcast distortion isn't an issue. There is a only a narrow window of power level difference between the strongest signal and the next-strongest signal where attenuation has the potential to be useful.
2. The second problem is that sticking the antenna in the paint can has to attenuate the signal EXACTLY the right amount to attenuate the weaker signal(s) below the receiver's noise level, but keep the strongest signal far above the noise level to get good decode. If you're off by more than a few dB, then you will still have high decode error rates, either because you haven't gotten rid of the simulcast distortion (not enough attenuation), or because you've attenuated all the strongest signal too close to the noise floor (too much attenuation).
In most cases where simulcast distortion is an issue, no amount of signal attenuation will help because the signal power levels from various towers will be too close together to successfully isolate one by attenuating the others below the noise floor. And even in the rare cases where the signal power levels differ enough for attenuation to potentially be useful, sticking the antenna in a paint can is unlikely to apply the correct amount of attenuation.
In summary, your solution works for you because of dumb luck--you have a mild case of simulcast where there is enough of a signal power difference for signal attenuation to have a chance of being useful, AND sticking your antenna in a paint can just happens to attenuate the signal the correct amount for YOUR specific reception conditions. But neither of those conditions are likely to be true for anyone else trying your advice.
A variable attenuator has a better chance of working than sticking the antenna in a paint can, because you can control the amount of attenuation, and adjust it for best decode. But even that won't help in situations where the signal levels of the various towers are within a few dB of each other.
