# Distortion in the transmitted audio

**URL:** <https://forum.digirig.net/t/distortion-in-the-transmitted-audio/4972>\
**Category:** Uncategorized\
**Tags:** baofeng-uv-5r, troubleshoot-audio\
**Created:** [December 14, 2024, 9:52pm UTC](https://forum.digirig.net/t/distortion-in-the-transmitted-audio/4972 "2024-12-14T21:52:08Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![G7NRU](https://forum.digirig.net/user_avatar/forum.digirig.net/g7nru/32/3713_2.png) [@G7NRU](https://forum.digirig.net/u/G7NRU)\
**Post date:** [December 14, 2024, 9:52pm UTC](https://forum.digirig.net/t/distortion-in-the-transmitted-audio/4972/1 "2024-12-14T21:52:08Z")

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Hi all,

I have a little mobile digirig connected to a Baofeng UV5RH handheld. I am using it with direwolf and a raspberry pi for APRS.

The problem I have is that sometimes there are weird noises being transmitted on the carrier along with the audio from Direwolf. The cable is one that i made up following instructions I found on here.

Even if I disconnect the pi and manually key the radio, I get the same noise so its definitely coming from the digirig. If I disconnect the digirig, the carrier is silent so the radio is OK.

What makes it especially strange is that it doesn’t happen all the time. But, it will happen for a few hours and then miraculously clear.

I am really not sure what to do now. I am sure its the Digirig, but not sure what I can do about it.

Here you can hear it: [https://youtube.com/shorts/Y2TWEbMcsGE](https://youtube.com/shorts/Y2TWEbMcsGE)

This another radio that is listening to what is being transmitted when I manually key the PTT. If I disconnect the digirig, problem solved. I am at a loss!

Any ideas welcome!

73s G7NRU

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**Author:** ![G7NRU](https://forum.digirig.net/user_avatar/forum.digirig.net/g7nru/32/3713_2.png) [@G7NRU](https://forum.digirig.net/u/G7NRU)\
**Post date:** [December 14, 2024, 11:16pm UTC](https://forum.digirig.net/t/distortion-in-the-transmitted-audio/4972/2 "2024-12-14T23:16:25Z")

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Replying to my own post!

Further investigation has shown that I can stop this noise if I disconnect the handheld from its USB charger too - so maybe some sort of ground loop… …

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**Author:** ![webmonkey](https://forum.digirig.net/user_avatar/forum.digirig.net/webmonkey/32/2494_2.png) [@webmonkey](https://forum.digirig.net/u/webmonkey)\
**Post date:** [December 14, 2024, 11:41pm UTC](https://forum.digirig.net/t/distortion-in-the-transmitted-audio/4972/3 "2024-12-14T23:41:00Z")

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yes, the battery charger has little to no filtering.

add the usb attachment and you’ve got rfi finding an easy path to the tx audio.  
just not built to run with the charger plugged in  
☹

glad you tracked down the culprit though!

good luck  
kb0wlf