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Off Topic Wireless - If it receives or transmits and it doesn't fit in anywhere else, WayneH will probably move it here

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Old 08-15-2018, 10:54 AM
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Default The Strange David and Goliath Saga of Radio Frequencies

https://www.wired.com/story/wireless...cies-fcc-saga/
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Old 08-15-2018, 10:22 PM
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Wireless microphone systems typically have only 50 mW (fifty one thousandths of one watt!) or less output power. So in other words, they operate with less than 150 mW, which means they are Part 15, and can be anywhere they want as long as they don't interfere with a licensed service. What is 50mW going to interfere with?

Yes, like the article says the sound people need to coordinate and make sure they don't have two mikes on the same frequency.

Last edited by Golay; 08-15-2018 at 10:27 PM..
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Old 08-16-2018, 3:35 PM
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A wireless mic will interfere with digital devices that use the same frequency and those digital transmissions will interfere with the wireless mics. A base station on a nearby building will wipe out the wireless mics. Go ahead and "coordinate" your way around that.
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Old 08-17-2018, 6:03 AM
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Default You are absolutely right

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Originally Posted by slicerwizard View Post
A wireless mic will interfere with digital devices that use the same frequency and those digital transmissions will interfere with the wireless mics. A base station on a nearby building will wipe out the wireless mics. Go ahead and "coordinate" your way around that.
Read what the article is about.

You are correct, a powerful "base station" could wipe out the wireless mikes. And wireless mikes must accept that interference. And someone in the audience with a 5G device disrupting a performance is not only a possibility, but will probably happen more than a time or two. But that's not what the article is about.

The article is implying everyone using wireless mikes must move, or be in violation of FCC regulations. That's not true. It says right in there that the production companies on Broadway are staying put wherever they want, and not worrying about this. They are using 50mW Part 15 devices. If the deep pockets on Broadway are not worrying about this, neither should the small churches, community theaters, etc.
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Old 08-17-2018, 9:07 AM
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Originally Posted by Golay View Post
What is 50mW going to interfere with?
If I put my service monitor on an antenna, I can access repeaters 25 miles away with 1 mw. I once had to df a wireless microphone getting into a public safety system a few miles away.

Convert that 50mw to dbm, then calculate a link budget into a receiver with a -125 dbm threshold and a 10 db gain antenna. You'd be surprised at how far it'll go.
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Old 11-09-2018, 3:00 AM
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Quote:
Originally Posted by zz0468 View Post
If I put my service monitor on an antenna, I can access repeaters 25 miles away with 1 mw. I once had to df a wireless microphone getting into a public safety system a few miles away.

Convert that 50mw to dbm, then calculate a link budget into a receiver with a -125 dbm threshold and a 10 db gain antenna. You'd be surprised at how far it'll go.
No you didn't, whacker. Everyone on here is always made up grandiose stories about working in law enforcement or radio shops. People use 700 MHz mics all the times and nothing happens, just gonna have to accept it.
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Old 11-09-2018, 8:32 AM
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Originally Posted by Pro-91 View Post
No you didn't, whacker.

I have seen a 25w VHF radio on a dummy load key a repeater 30+ miles away.

I have also heard an Icom UHF repeater with a cooked PA(exciter power only) with 150 metres of 30+ year old 7/8 Alucel hardline and a 30+ year old Sinclair 310-C4 6dB gain antenna from 25+miles away. 50mW is more than sufficient to cause interference.



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Old 11-09-2018, 11:16 AM
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No you didn't, whacker.
I very much did.

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Originally Posted by Pro-91 View Post
Everyone on here is always made up grandiose stories about working in law enforcement or radio shops.
What an idiotic thing to say.

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Originally Posted by Pro-91 View Post
People use 700 MHz mics all the times and nothing happens, just gonna have to accept it.
Sometimes nothing happens. Sometimes something does.

Actual facts exist outside of your personal beliefs. Just stay out of the way so the adults can deal with it. Your opinion is wrong, and we don't need your help.
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