1 Antenna 2 feeds

ke4ldu

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Taylorsville, North Carolina
Has any run into a issue where you have 2 feeds running on 1 raspberry pi and using 1 antenna where the audio mixes on both feeds? When I use 2 separate antennas and the audio mixing goes away.
 

jonwienke

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A ground loop isolator is probably the solution.
 

BF8609

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Oct 11, 2020
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Saint John, In
It could be IF traveling via ant wire back thru whatever you're using to split the feed. if you can find a small amp install it on one leg of the split and pad it down to to have zero gain the amp will stop any signals traveling backwards
 

ke4ldu

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Nov 4, 2009
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Taylorsville, North Carolina
So I tried the audio ground loop isolator. It didn't solve the issue. I order this isolator per the instructions of the Mr. Blanton Founder and CEO of Broadcastify. Is there a ground loop isolator that goes on coax for an antenna? It makes no sense at all the audio would mix just because 1 antenna is connected via a T connector to 2 radios.
 

bunangst

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Mar 12, 2013
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Harmony, NJ
So I tried the audio ground loop isolator. It didn't solve the issue. I order this isolator per the instructions of the Mr. Blanton Founder and CEO of Broadcastify. Is there a ground loop isolator that goes on coax for an antenna? It makes no sense at all the audio would mix just because 1 antenna is connected via a T connector to 2 radios.
Are you using the same model or even the same brand radios?

As BF8609 mentioned above....It seems like the IF (intermediate frequency) is travelling back the antenna cables and through the T Connector.

With two separate antennas, the very low IF signals are likely a high mismatch to the antennas and will radiate very poorly at best.
With a T splitter in place, the IF's from both radios have a direct path to each other.

See the link below on that describes RF mixing and Intermediate Frequencies used in receivers.
Superheterodyne receiver - Wikipedia
 
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