flyrotary@lancaironline.net Mailing List Archive

I hear you on the coffee!! (Although I’m a Tea man myself).

That’s my suspicion – that there is something on either the PTT ground run or on the Mic run. However, remember it is only when the engine is running – and also remember that in a Cozy that bad boy is 8 feet from the instrument panel. So, since it’s only there when the mic is keyed it has to be something that gets energized on the PTT ground wire or on Mic cable only when the engine is going.

Unfortunately no oscilloscope – wouldn’t know what to do with it if I had one! My usual instruments for testing electrical things is a wet finger and a pair of ear plugs – it hurts my ears when I find a live wire, hence the ear plugs. J

Joe Hull

Cozy Mk-IV #991 (Done Building! In Phase1 Flight Test - 0 hrs flown)

Redmond (Seattle), Washington

From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Joe Berki
Sent: Saturday, April 08, 2006 4:57 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Radio Saga Beginning

Joe,

Disreguard the previous message. I need coffee. Look at how the mike cable is grounded. You may have a ground loop in that circuit. The shield should be grounded at one point. There might be noise on the ptt line also. Do you have an oscilliscope?

Joe Berki

Limo EZ

----- Original Message -----

From: Bulent Aliev

To: Rotary motors in aircraft

Sent: Saturday, April 08, 2006 1:20 AM

Subject: [FlyRotary] Re: Radio Saga Beginning

Beats me Joe? I was also like a babe in the woods with my radio, until I installed a new Icom and small and simple intercom. Now is perfect. RST is on my desk ready for Ebay.

My fuel pumps used to make lots of noise also?

Buly

On Apr 8, 2006, at 12:11 AM, Joe Hull wrote:

Hey Buly (and anyone else)

I’ve got an RST intercom and an ICOM radio (don’t remember the number but only 1 year old). When the engine is off I can hear and Xmit fine. Turn the engine on and I can still hear fine (i.e. no noise) but when I key the mic there is a ton of noise in my headset and in the broadcast. It’s not high pitched just a mid-range noise.

I ruled out the alternator by taking the belt off – noise was still there.

So why noise only when I transmit? Any thoughts?

Joe Hull

Cozy Mk-IV #991 (Done Building! In Phase1 Flight Test - 0 hrs flown)

Redmond (Seattle), Washington