PTT microphone volume

[linzhiming]

Hello all,

Some of my passengers have complained to me that although they can hear me well during normal intercom usage, they do not hear me properly whilst I am transmitting with the PTT button pressed, i.e. they say that the volume of my voice during a transmission is really low. Furthermore, they have no problems hearing the normal COM transmissions that are received, i.e. in receiving, not in transmitting mode.

I have been trying to figure out whether this is caused by the pilot microphone squelch setting and tried the manual squelch mode but without any success (presumably because this is the general microphone squelch and not any PTT-specific setting). Given that the problem seems to occur only with the PTT button pressed, I wonder whether it is an internal system setting that might needs tweaking. When I looked through the G1000 line maintenance and configuration manual just now, I found a setting called "MIC GAIN" which curiously is listed under the COM setup page (and not the GMA configuration page).

Does anyone know what the cause of the issue could be and how it could be fixed? I have experienced the problem on two different DA40 aircraft. Given that I have not seen anyone else report this in this forum, I doubt that it is an issue with the DA40 G1000 default setting so would be interested in any thoughts...

Wolfgang

[carym]

I, too, am interested in other's responses to this. I have experienced the same issue in multiple different airplanes with multiple different intercoms. Therefore, I am suspicious that this may be a very common intercom phenomenon for which there is no easy solution.

[Colin]

I believe it is called "sideband volume" and the techs seem to reset it when doing a software update or messing around with the G1000 stuff. Sometimes I get my plane back from annual and it is loud, other times it is too soft to hear.

But I don't know how they adjust it.

[linzhiming]

I believe it is called "sideband volume" and the techs seem to reset it when doing a software update or messing around with the G1000 stuff. Sometimes I get my plane back from annual and it is loud, other times it is too soft to hear.

But I don't know how they adjust it.

Thanks, Colin. I will give adjusting it a try (described in the G1000 line maintenance manual which I had posted in a different thread) and report back.

Wolfgang

[Rick]

I am also having the same problem in my DA40. There used to be a sidetone volume setting in the G1000 audio configuration, but it has disappeared in the latest release. During my just-completed annual we searched for a solution, including a lengthy conversation with Garmin, but came up with nothing. I suspect the sidetone setting has defaulted back to some unreasonably low value, and we have no way to adjust it now in the configuration.

I have not tried this yet, but a possible improvement might be to lower the radio volume and the intercom volume a bit, then turn UP the headset volume, and see if this makes it easier to hear the sidetone. There seem to be three different volume settings in the G1000. The intercom level (how you hear conversations within the plane) is controlled by the knob at the bottom of the audio panel. The radio receive level (how you hear ATC) is controlled by the knob at the top. The sidetone level (what you hear when the PTT button is pressed) doesn't seem to have any adjustment after the latest software release.

[linzhiming]

I believe it is called "sideband volume" and the techs seem to reset it when doing a software update or messing around with the G1000 stuff. Sometimes I get my plane back from annual and it is loud, other times it is too soft to hear.

But I don't know how they adjust it.

Thanks, Colin. I will give adjusting it a try (described in the G1000 line maintenance manual which I had posted in a different thread) and report back.

Wolfgang

I have finally got around to adjusting and testing it and it seems to work! The parameter value is indeed called SIDETONE and is found under the COM setup page of the GIA unit in maintenance mode. My value was set to 14 and I changed it to 25 (allowable range is 0 to 63). I might set it to 30 in the end but 25 was audible enough.

Wolfgang

[JamesDS]

Thanks, Wolfgang. I will reset this at the next annual, coming soon.

[Nirbm01]

Hi,

I have the same issue, I went into the setup and changed the sidetome - but how to you save the change? couldnt figure it out.

Thanks,
Nir

I believe it is called "sideband volume" and the techs seem to reset it when doing a software update or messing around with the G1000 stuff. Sometimes I get my plane back from annual and it is loud, other times it is too soft to hear.

But I don't know how they adjust it.

Thanks, Colin. I will give adjusting it a try (described in the G1000 line maintenance manual which I had posted in a different thread) and report back.

Wolfgang

I have finally got around to adjusting and testing it and it seems to work! The parameter value is indeed called SIDETONE and is found under the COM setup page of the GIA unit in maintenance mode. My value was set to 14 and I changed it to 25 (allowable range is 0 to 63). I might set it to 30 in the end but 25 was audible enough.

Wolfgang

[Rick]

Nir and Wolfgang,

Where in the configuration did you guys find the sidetone volume adjustment? I know where this setting was in the previous software versions, but I can't find it anywhere in the latest (321.23) version. What version of the G1000 software do you have?

Thanks!

[Nirbm01]

Hi,

COM page under GIA.

I am running the latest before on the 2007 XL (no WAAS)

But no clue on how to save the changes.
Nir