Intercom with separate PTT for COM1 and COM2?

Discussion in 'Avionics and Upgrades' started by iamtheari, Nov 26, 2017.

  1. iamtheari

    iamtheari Cleared for Takeoff

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    Is there an intercom that can be configured with separate PTT switches for COM1 and COM2? Most will have two PTT inputs, one for the pilot and one for the copilot, and then a selection between transmitting on COM1 and COM2, but I am trying to find an intercom that will let me put two PTT switches on the pilot's side (and ideally also two on the copilot's side) to transmit on the separate radios without switching between them on the intercom face panel. I don't even know what this feature might be called. Has anyone seen this in a GA unit?
     
  2. Ravioli

    Ravioli Final Approach

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    There are many with Com1/Com2 separation... BUT... that is for when the left seater is transmitting on one radio and right seater is on the other.

    The cabling would be semi-problematic.

    So, what's the use case for this interesting set-up?
     
  3. JScarry

    JScarry Pre-Flight

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    I haven’t seen what you are looking for but my PMA6000 lets the pilot and co-pilot talk at the same time using two different radios.

    Turning the rotary switch to COM 1/COM 2 places the PMA6000 into "Split Mode". This places the pilot on Com 1 and the copilot on Com 2. Pilot and copilot are isolated from each other on the intercom, but can use their respective radios simultaneously. An example of this useful feature is when the pilot may want to talk to Air Traffic Control, while the copilot may be speaking to Flight Watch.

    The "Split Mode" radio selection can be reversed by switching to COM 2/COM l. The pilot will be on Com 2 and the copilot will be on Com 1. A third "Split Mode" selection is TEL/COM l. This will place the pilot on airborne radiotelephone, HF or other transceiver (if installed), while the copilot will be on Com 1.
     
  4. iamtheari

    iamtheari Cleared for Takeoff

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    The use case is formation flight. Lead could COM2 to your flight and COM1 to the tower and talk to both without having to take his hand off the stick. Corner case and one I am not likely to encounter, but something I thought of in day-dreaming about what radios to put into the Van’s RV that I’m not going to build. :)
     
  5. Ravioli

    Ravioli Final Approach

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    In reality, lead would be monitoring one radio (ground services) and talking primarily on the other to the flight. When need he'd switch with the audio panel.

    There's always a free hand, since nobody flies with both hands on the yoke, stick, or whatchamallit. I can't imagine how you can have both hands on the stick of an RV. And even more strange, how someone got a PPL with out guarding the power controls on takeoff and landing.
     
  6. iamtheari

    iamtheari Cleared for Takeoff

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    I don’t understand this part of your post.
     
  7. Ravioli

    Ravioli Final Approach

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    You wrote: "Lead could COM2 to your flight and COM1 to the tower and talk to both without having to take his hand off the stick."

    There is usually a free hand.
     
  8. iamtheari

    iamtheari Cleared for Takeoff

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    ...except when operating or guarding the power controls, that is.
     
  9. Ravioli

    Ravioli Final Approach

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    Talk to your flight leader and see how much chit-chatting they are doing during the take-off, maneuvering, and landing phases of the flight. You'll find it to be a non-issue.

    Or, you can shock me by having them detail how they have wired it all up.
     
  10. iamtheari

    iamtheari Cleared for Takeoff

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    As mentioned, this is a corner case that I’m not likely to encounter. That’s because I don’t have anyone to fly formation with. :p It’s just a daydreaming exercise, thinking about all the possible ways there are to set up the radios in a plane.

    Incidentally, the GMA 245 can be wired to have a COM SWAP switch. That’s the one that switches the mic between COM1 and COM2. Given the vast cross-compatibility between different brands and models of audio panels, I suspect that most others allow for this wiring option as well. So that would be one option.
     
  11. weirdjim

    weirdjim En-Route

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    Every RST Engineering intercom that was ever made had this option. The thought was that one of the PTT switches was given priority and that was the microphone that went to the com radio. If the other PTT was pressed, it had no effect. The thought was that you could make the pilot priority in a personal airplane that if the copilot was saying something that the pilot objected to that the pilot could over-ride the copilot. If you made the copilot priority in a training aircraft, the instructor had priority and could override the student.

    I was always curious why I was the only one that thought this way.

    Jim
     
  12. WannFly

    WannFly En-Route

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    And now I know what the split thing on SL 15 is all about. Thanks.

    Sent from my SM-G935V using Tapatalk
     
  13. flyingron

    flyingron Touchdown! Greaser!

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    The Garmin and PS engineering audio panels both have split mode. Of course, that's only as good as the radio/antenna systems installed. You may have interference between the two.