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Ron Hardin wrote:
My general impression of modern receivers is that they're already really sensitive. You get more signal and equally more noise from a bigger antenna, so you're not ahead once you're above the internal noise of the receiver, which is what is low in modern receivers and so you don't see much advantage once you're beyond the minimum antenna. On the other hand, you get increased intermodulation and overload from other signals you're not meaning to listen to, and that's something modern receivers are not designed to suppress, mostly. So it's likely you'd need a preselector to drive down the unwanted overloading signals; possibly you'll hear more then on the frequency you're tuned to. Alternatively your outdoor antenna can be a low noise one, and give you an advantage you don't get indoors. Ie. designed not to pick up signals and noise you don't want to hear. Whether this is dimmer noise from neighbors or power pole insulators breaking down, or some local broadcaster, depends on your situation. I use active antennas outdoors and phase them to produce nulls, chiefly on MW. Nulling SW signals that are not locally produced is difficult by phasing though, unless you have a huge number of elements to produce an extended null. A passive pre-selector is almost mandatory when using a good external antenna with a sensitive portable like the SW77. I had to do this with my '2010'. Otherwise the bands were full of spurious signals (intermod's). -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |