sest1000
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Joined: Sat Feb 23, 2019 8:09 am

Pi 3 b+ disturbing our Motorola comradios for firefighting.

Sat Feb 23, 2019 8:16 am

Hello

at my work we have som problem with our new pi 3 b+. They are sending something that our smokediving radios receives. It results in battery drain when we leave the radions on.

I have tried to disable bt and wifi but it dosent help.

I made dtoverlay settings to config file on pi. are there anything else I can try with?

Thanks for the help

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davidcoton
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Re: Pi 3 b+ disturbing our Motorola comradios for firefighting.

Sat Feb 23, 2019 9:38 am

Put the Pi in an earthed metal case, being careful NOT to short anything.
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Paul Hutch
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Re: Pi 3 b+ disturbing our Motorola comradios for firefighting.

Sat Feb 23, 2019 2:54 pm

Assuming the radios are on a reserved or licensed frequency band then it seems unlikley the Pi itself is the main culprit, it is more likely peripheral circuitry.

To test this run the Pi with nothing but a power connection.

If as I suspect there is no interference signal then start adding back peripherals one at a time until the interference re-appears.

If the Pi with power only still causes the interference then do as David suggested above above and try a metal case.

W. H. Heydt
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Re: Pi 3 b+ disturbing our Motorola comradios for firefighting.

Sat Feb 23, 2019 4:59 pm

Another item to look into is the PSU. If it's the official RPF PSU, it's probably been properly certified. Otherwise, all bets are off.

If the test suggested above of just the Pi and nothing connected, try putting a conductive shield around the PSU and as much of the connecting cable as possible.

sest1000
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Joined: Sat Feb 23, 2019 8:09 am

Re: Pi 3 b+ disturbing our Motorola comradios for firefighting.

Sun Feb 24, 2019 2:48 pm

If I test with a raspberry pi 2 there is no interference.

I have only made dtoverlays in config file. Is there any more I can do?

Do you Think a metalcase will help?

Best regards

stevecobb76
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Re: Pi 3 b+ disturbing our Motorola comradios for firefighting.

Wed Feb 27, 2019 3:23 am

lead box or faraday cage? spell check??

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Burngate
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Re: Pi 3 b+ disturbing our Motorola comradios for firefighting.

Wed Feb 27, 2019 9:29 am

sest1000 wrote:
Sun Feb 24, 2019 2:48 pm
If I test with a raspberry pi 2 there is no interference.
As I understand it, the major differences between the Pi 2B and 3B+ are the WiFi/BT as you've noted, and the clock speed - 2B runs slower.
Would it be worthwhile testing the 3B+ with a lower clock speed?

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