In Reply to: Re: Columbia tower scratchy? posted by Dick H on September 15, 2000 at 16:21:52:
Any very strong signal has the potential to interfere with a receiver. An example would be listening to a radio station on your car radio and driving by the antenna array for another station. Your desired station can be totally blocked until you pass.
Another example would be if you shine a flashlight at nite, it appears to work pretty well. As the sun comes up, it becomes harder and harder to see the light. Radios work the same in that the "front end" or amplifiers closest to the antenna can be overloaded with close (in frequency) high power signals. Some types of modulation can cause more "interference" than others. Digital modulation is one of these. Nextel uses digital modulation on frequencies close to "regular" 2-way radio. Thus, you see their name pop up a lot. Cellular is in another, but close, band and so does not cause as much of a problem (but still can cause a problem).
Wiz
: : Since a lot of folks on this board seem to be quite confused over the differences between simplex, repeater, trunking, simulcast, SmartZone, talkgroup, and frequency, would anyone be interested if I put together and posted some basic explanations?
: : Wiz, System-wide Manager
: : King County Trunked Radio System
: That should help lots of people on this board. When it's posted I'd like to put it on the www.strongsignals.net trunking board as well.
: BTW, do you have any comment about the previous post that suggests overload from a cell phone site? From what I've heard it is a rather common problem country-wide. It seems to be a problem here in Portland, too.
: