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Post by Deleted on Aug 7, 2014 2:05:37 GMT
I think the word "proximity" is like saying "close", But the problem is that "close" is one of those English words that has two different uses, like "lead." So let's use "proximity."
How proximitus can two AM transmitting antennas be without interfering with each other?
Consider a transmitter/antenna at 1640 kHz and another transmitter/antenna at 1680 kHz. If they are one-foot apart each one will induce its signal into the other and modulation heck will erupt.
How far apart do the transmitter/antennas need to be to avoid interference between them? 10-feet? 20-feet? 30-feet? 40-feet?
Another word with dual use is "feet", so I hope nobody mentions shoes.
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Post by Admin on Aug 13, 2014 13:35:02 GMT
I've heard of "spurs" being generated when two signals mix in a non-linear junction such as a rusty or corroded connection like a wire fence or other metal structure. This is not a case where the signal is back-feeding into the transmitter and mixing, rather it is completely external to the sources of the signals.
I suppose the same could happen within the transmitter since your frequencies are very close. Otherwise the filtering effect of the tuned antenna and output stage would attenuate the offending back-fed signal.
I don't suppose too many Part 15'ers have tried multiple transmitters in close proximity (there's that word.) You'll be on the bleeding edge of research for The ALPB.
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Post by Admin on May 17, 2015 0:13:44 GMT
So, how did that experiment go? There has been some discussion at Part15.us about a similar situation.
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Post by Deleted on May 28, 2015 12:15:04 GMT
Life is passing through a slow motion vortex and the proximity experiment hasn't happened yet.
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