Avionicshttp://www.jets.dk/cs/forums/27/ShowForum.aspxLooking for Avionics ?en-USCommunityServer 2.0 (Build: 60526.2668)Noise Problems When Transmitting on TFM VHF Radiohttp://www.jets.dk/cs/forums/thread/7560.aspxTue, 12 May 2009 08:43:59 GMTa23efcf1-9e75-4ff9-be18-cd9cb68b9485:7560colorado skydiver0http://www.jets.dk/cs/forums/thread/7560.aspxhttp://www.jets.dk/cs/forums/commentrss.aspx?SectionID=27&PostID=7560We have 3 VHF radios in a Bell 206L-1. The #1 is with a Garmin 420, the #2 is a Collins and the #3 is a Technisonic. If I am monitoring all 3 radios and transmitt on the #3 there is very loud noise level on the side tone. If I have the #1 and #2 on the same frequency only the #1 is a problem. I appears that the #3 when transmitting is breaking the squelch on the #1 and is transmitting only noise on the #1. If I deselect the #1 and do not monitor it the side tone goes crystal clear. <br /> <br />We have relocated antennas, installed a grounding plane with the one Technisonic that was mounted on fiberglass. We even replaced the Technisonic with another unit. A noise filter was installed and none of this resolved the problem. <br /> <br />I was wondering if anyone out there has had similar probems or has any fresh ideas.