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HPDE - Radio Interference w/Engine Speed

Hi Folks,

Hope everyone is well.

I went to my regional PCA group's HPDE day this weekend and noticed that when I have the radio turned on to chat with my instructors, there is an audible whine or "interference" if you will, and the pitch adjusts to the engine speed.

Is this normal or is there something I need to look at more seriously? My guess are some grounding points but I'm not even sure where to start. Any leads appreciated. Thanks!

Quote:

Originally Posted by bcrdukes (Post 646990)

You have interference from a ground loop. You can buy loop isolators for headphone and RCA jacks online. They are not perfect but work well. Otherwise you need to ground your audio system directly to the battery.

Sent from my SM-G970U1 using Tapatalk

I should clarify - the radio I am referring to is the radio box between me and my instructor, the on dashboard radio/deck. Thanks!

Many intercom communicators have this issue.

HMS' Trac-Com's v2.0 has greatly reduced this feedback/interference issue compared to their v1.0 and the Chatterboxes out there. For a while HMS was offering a reduced price to upgrade to v2 from v1 - not sure if they still do but worth the ask.

https://www.hmsmotorsport.com/item/trac-com-intercom-v2/trac-com

Good luck! :)

Yes, I assumed as such. This is a common problem with aftermarket audio installs.

You have a headset, yes ? (I'm assuming your system isn't wireless)

Try this (for 3.5mm back) - https://www.amazon.com/BESIGN-Ground-Isolator-Stereo-System/dp/B06XQYN77L/ref=asc_df_B06XQYN77L/?tag=hyprod-20&linkCode=df0&hvadid=198076596450&hvpos=&hvnetw= g&hvrand=1257800385607848135&hvpone=&hvptwo=&hvqmt =&hvdev=m&hvdvcmdl=&hvlocint=&hvlocphy=21156&hvtar gid=pla-350233567378&psc=1

Sent from my SM-G970U1 using Tapatalk

Quote:

Originally Posted by Burg Boxster (Post 647027)

Quote:

Originally Posted by ike84 (Post 647034)

Yes, I assumed as such. This is a common problem with aftermarket audio installs.

You have a headset, yes ? (I'm assuming your system isn't wireless)

*Edited*

This is the exact radio our club uses.

And yes, I am plugged in to the box using the student helmet boom. The feedback pitch goes up and down with my engine speed, so I'm not sure if its my Continental aftermarket radio that needs to be further ground or if it's something else. I took out the CDR-220 as it was defective and installed a factory look-alike from Continental. For what it's worth, the Continental head unit is turned off during instruction.