My voice is really hard to hear when transmitting

[CGameProgrammer]

My helmet/headset has a 150-ohm microphone impedance and my voice is really quiet and hard to hear when transmitting over the radio, although the intercom picks up my speech without any issue. Also, when doing the gain test in radio setup, it always says "LOW" no matter what gain I use (even 100%) or how loudly I speak.

What could cause this? Incoming broadcasts are loud and clear.

 

[hufise]

Hi you unknown

In the most Radio you have to rise the sidetone value to hear your self in the headphones

From Daniel

Flying RV12, Switzerland

 

[CGameProgrammer]

I'm not talking about sidetone of course. Other people, including ATC, can barely understand me because my transmissions are so quiet. I have confirmed this downloading archives on liveatc.net.

But, again, on the intercom it sounds just fine, and I sometimes record flights with a GoPro hooked into the audio, and the camera records my voice loud and clear. It's only outgoing transmissions via the radio that are very quiet.

 

[mmarien]

f you have some way of checking the draw when you PTT would be a way of checking the radio output. It should draw the full 3A (or whatever it's rated at). The SV AMP gauge should show that without the alternator running.

 

[CGameProgrammer]

The amp input does not seem to be connected on mine; I didnt create the wiring harnesses so not sure if it was overlooked or what. I will try to hook up something somewhere to read current draw... the power input for the radio is easily accessed.

Speaking of which, radio power does go through a noise filter, called the Eliminator by Lone Star. Not sure if relevant.

 

[Dynon]

Does your headset microphone have an adjustable gain screw?

 

[CGameProgrammer]

I'm pretty sure it does not but I'll verify with the manufacturer. But my voice sounds loud and clear on the intercom, verified with passengers conversing with me, the camera recording audio, and sidetone. All are loud and clear. So I suspect that is not the problem...

 

[CGameProgrammer]

The microphone does not have a gain screw.

 

[jakej]

The microphone does not have a gain screw.

What make of headset ?

Did you try another headset to determine whether it's the headset mic ?
What radio are you using ?
Did you test without the GoPro connected to the audio?

 

[CGameProgrammer]

The helmet is by Flycom using Peltor speakers but I do not know who makes the mike. The website only says it is a 150 ohm electret mike. Today I did borrow another headset and my voice was loud and clear with it so I have no idea what is wrong with the mike. Both helmets have the same issue.

 

[jakej]

Looks like you now know the answer And.... you didn't contact them in the first instance? :
A simple search found this http://www.flycom.co.uk/page.php?Custom%20Pages=3
also http://www.flycom.co.uk/imagesupload/cms_files/Trouble%20Shooting.pdf

 

[CGameProgrammer]

I did contact them but they have not responded.

 

[CGameProgrammer]

I noticed Pilot USA sells a couple of 150-ohm microphones and the product page states "pre-amp required for general aviation". So perhaps 150-ohm microphones are not directly compatible with the radio? Does anyone know what sort of microphones are required, or if there exists some kind of amplifier I can put inline with the mike plug?