New plane but cant hear when broadcasting

jd21476

jd21476

Line Up and Wait
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jd21476
So my new to me 1959 Comanche has some older radios that all work well and I dont want to spend the expense of swapping them out right now. I can talk to the passenger and he can talk back and its fine. When I key the mic to call the tower they can hear me just fine but I dont get any audio in my headset nor does the passenger. I put a picture of my stack below. Am I doing something wrong?
 

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Somethings up with your side tone on the old narco, do you have audio on comm 2?

Sent from my SM-G960U1 using Tapatalk
 
Yes, we moved it between Crew, All, and Audio but still the same. It almost seems like Im missing something cause everything else works just fine.
 
jd21476 said:
Yes, I have audio on comm 2
Click to expand...
Sounds like either incorrect or broken wiring of com 1 or internal issue on com 1. Of course your options are limited with Narco if it is internal. I believe sidetone on these is configured via wiring of pins, rather than a setting

Sent from my SM-G960U1 using Tapatalk
 
I presume you have pushed the com1 button on your audio panel, it is not lit up? And the #2 radio appears it is on test versus on. I would tune in atis on both radios and then play around with the audio panel. Try pushing the speaker button on the audio panel to make sure it is not an issue with the wiring to the headset jacks. If the atis message is heard on the airplane speakers turn either #1 or #2 down and then reverse and try the other radio. This should tell you if it is one of the radios. If you hear atis on both then it is in the audio panel or wiring to the jacks. Then push the both button on the audio panel and repeat turning the volume up/down on each radio and see what you hear in the headsets. If the radios work on both then try the individual com1 then com2 buttons. Good luck.
 
It is the wiring on the intercom...
My 172 was the same way...
I talked to a avionic shop and they said the intercom can wire with or without sidetone when the PTT is activated.
i never worried about it and never changed it. I can hear myself in all the other planes i have...
 
Some old NARCO com radios had to be modified to provide sidetone. I'd ask the PO if it ever had sidetone.
 
pigpenracing said:
It is the wiring on the intercom...
My 172 was the same way...
I talked to a avionic shop and they said the intercom can wire with or without sidetone when the PTT is activated.
i never worried about it and never changed it. I can hear myself in all the other planes i have...
Click to expand...
I probably misinterpreted the op’s thread. I thought he could not hear the tower. After seeing your response that suggests he can’t hear his own voice?
 
It’s simply not set up for sidetone (hearing yourself speak when transmitting) or not available in the radio. Totally normal for some installations of that vintage.
 
I may be the only person with a set, but my el cheapo noise cancelling no name headsets have a little "switch" in the battery box of the head set that would correct this in AC I rented ...
 
Yes, I can hear the tower I just cant hear myself. Its very odd. If its not set up for sidetone can it be changed or added?
 
jd21476 said:
Yes, I can hear the tower I just cant hear myself. Its very odd. If its not set up for sidetone can it be changed or added?
Click to expand...

Yes... Read my post above.
Take it to the avionic shop and they will reconfigure it. Whoever installed it probably did not want to hear themselves talk.
Why do you need to hear yourself?
A few flights and you will be used to it as is.
 
It is possible, but unlikely, that it was not wired properly.

It is also possible that the radio is either not providing sidetone, or the sidetone (which is adjustable in level by a potentiometer on the radio) is turned way down.

Finally, it is possible that there is an issue within the audio panel that is causing the issue, and that’s where I believe the problem most likely resides.

I believe that the two COM radios have the same plug configuration, and can be swapped; if so, you could swap them and see whether the problem followed the radio, or remained at the COM 1 position, in which event your troubleshooting would have been materially narrowed-down.
 
Got this on line: Pretty much confirms and summarizes above responses.



This is an issue of sidetone. Sidetone is the part of the microphone signal that is sent back to your headset so you can hear yourself talking. It's important that you get these audio cues so you know you ARE talking, and loud enough.

During radio transmissions, sidetone is created by the com radios, and serves to verify that everything is working. So while you are transmitting, the intercom is turned off and you are hearing what the aircraft radio is providing. Anyone who can hear the radios on the intercom will also hear the sidetone.

Sometimes, the com radio does not produce sidetone This is particularly true with ARC (Cessna) radios.

In these cases, the intercom or audio panel can be modified by an avionics shop to create an artificial sidetone in the intercom. This modification allows the intercom to continue to operate during radio transmissions, so what you are hearing is the intercom, not the radio.

In other cases, sidetone can be lost because of installation problems. This occurs when Radio Frequency Interference (RFI) enters the intercom wiring during transmit, and cancels the sidetone. We have found this is caused by incorrect jack wiring, usually because of grounding of the microphone jacks at the jack end to the airframe.

The ONLY place the jacks should be grounded is the intercom
 
Looks like a Narco 810+.

Google found the following snippet: "FWIW, the sidetone adjustment screw is hidden under the faceplate too, just to the left of and below the freq knob."

If it's not that ... most intercoms have a failsafe that routes the headset directly to the radio when the intercom fails or is turned off. See if you get a sidetone when you transmit with the intercom off.
 
Look at the manual for the radio installation. Even old installation manuals are available if you Google them. Sometimes sidetone is enabled by a jumper wire.
 
Turn the side tone way up so it sounds spiffy in headphones, and then turn on the overhead speaker while keyed up in transmit. :)

Bonus points if you do it on Ground. They love loud squeals in their headphones. LOL.

There’s a reason some installations have sidetone disabled... just sayin’...
 
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