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iPod adapter

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@ Mike


Thanks for the diagram, it definitely helps!

Just to make sure I fully understand this circuit, the transformer "steps" down the impedance of the aircraft to that of the mp3 player, and the headset...ie 100-500ohm to 10-30 ohm. Does the transformer also isolate the aircraft from the rest of the circuit? (That is what I understood from your example.)
I also realized the aircraft audio out is mono, can I use just one transformer, prior to splitting the signal?
Can I also drop the pot? As I don't need a separate volume control, or does it serve another purpose?
In your illustration R1(1/2w, 10ohm resistor), is there to protect the Garmin in your case, mp3 in mine....Right?



I'm sorry for so many questions, but as you can probably tell I'm not an engineer, and I'm new at this stuff. I am reading books and trying to learn, and I apologize. I appreciate everyones help!
 
I'm assuming your aviation headset has a mono/stereo switch and has a stereo plug (Tip, Ring and Sleeve)? Is that right?

Try this:

(The other occupants of the aircraft will hear the IPod at a reduced level)
 

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@Mike

Yes you are correct. My headset has a mono/stereo switch. This is exactly what my circuit currently looks like, except I don't have any resistors. I will add them. Thanks!!
 
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@ Mike

I added the resistors to the circuit. That seemed to do the trick! All the audio sources have good range of volume, and no distortion!!! Thanks for all the help. One plus is only I can hear the music, so its almost perfect. Only complaint is when iPod is attached and turned on the over all volume is reduced. Is there a reason this happens or is there a simple solution? If not I can live with it. Thanks for all your help! Your knowledge is appreciated!
 
One way to add the IPod audio to the aircraft audio without reducing the aircraft audio (as much) would be to use two transformers as I posted earlier.
The other way is to build a true "summer" using two opamps or LM386s.

I am doing this in my 182. It had a mono audio panel (King KMA24). I didn't want to rewire the entire avionics setup just to add stereo headphones, so I build a two-channel stereo amp consisting of two LM386s. Only the four headphone jacks had to be replaced with stereo jacks.

The L & R channels are configured as a summing amp, adding the L & R stereo from an XM/CD/Ipod to the mono output of the existing audio panel. Both ears get the mono aircraft signal summed with the respective L & R entertainment audio. Since the amps are true summers, there is no change in level when the entertainment is switched on/off. A center-off toggle switch (like the ones in the audio panel) conditionally adds two different entertainment sources to the aircraft audio, which obviously cannot be switched off...
 
Hello,
Is there a simple way to connect the ipod/iphone to the mic jack of the aircraft to hear music through the PA while I am in the turnaround waiting for the next flight?

Would one of the schematics posted above do the job?
Would I need to implement a swicth to do the push to talk function of the mic?

Thank you
 
Eduotro, a circuit to feed an IPOD into an aircraft's mic input sounds like an accident waiting to happen. To hear the music over the cabin speaker, you would have to select Public Address (main cabin announcement) and then key the PTT. But what happens if you screw up, and switch the audio selector back to normal COM mode. You would be keying one of the COM transmitters, and playing music to ATC. Sounds like something that could get you fired...
 
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