Garmin GNC255 - DME?

Discussion in 'Avionics and Upgrades' started by CC268, Mar 13, 2018.

  1. CC268

    CC268 En-Route

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    Flew my plane for the first time last night with the new G5 HSI and GNC255. Good stuff. I noticed the GNC255 gives you what looks to be full DME info (distance to station, bearing to station, time to station, etc) - pretty cool. Unfortunately, there is no Supplemental AFM that makes it legal to use as a DME - at least from what I can find.

    I believe the SL30 has the ability to be used as DME. Why wouldn't Garmin make their newest radio capable of being used as a DME, but the last generation radio was?

    Not a huge deal, we didn't buy the radio to be used as a DME, but it was cool/surprising to see all the capabilites of the radio included what looked to be all the info you would get on any older DME.
     
  2. bnt83

    bnt83 Final Approach

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  3. CC268

    CC268 En-Route

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  4. bnt83

    bnt83 Final Approach

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    I've never heard of a NAV/COM/DME before. But the NAV boards in radios typically have optional DME tuning, that means when you dial in a stattion on the nav it will auto tune the connected DME radio to the appropriate DME frequency. This is very common. I'm not sure how many NAV/COMs will actually display the DME data but this one obviously can.
     
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  5. CC268

    CC268 En-Route

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    Gotcha - oh well, not a big deal. Just thought I'd ask on here about it.
     
  6. bnt83

    bnt83 Final Approach

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    Flown it much since you got them goodies installed?
     
  7. CC268

    CC268 En-Route

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    No last night was the first time. I've been insanely busy between getting married, honeymoon, moving into a new condo, etc. There are a few bugs that need to be worked out - avionics shop is taking a look at these issues today. The HSI is worth its weight in gold...absolutely awesome. The radio is amazing too. As soon as we have the few issues ironed out I should be ready for my IR checkride in a few weeks.
     
  8. Mtns2Skies

    Mtns2Skies Super Moderator Management Council Member

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    So to get DME (or fake DME) displayed on a GNC255, do you need a DME antenna installed for this? Or is it pulling that information through the VOR antenna?

    The handbook mentions DME sensor... what is that exactly?
     
  9. bnt83

    bnt83 Final Approach

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    The GNC255 is NOT a DME transceiver, it must get that information from a DME transceiver (for real DME) or a GPS (fake DME).

    Basically there are two DME transceivers, panel mounted which will have a display and transceiver in the instrument panel mounted chassis and remote mounted which only the display is panel mounted. The GNC255 can replace the display on the remote mounted DME transceiver.

    All DME transceivers must be tuned, the GNC255 can do that for you. All DME transceivers will need their own antenna.
     
    Last edited: Aug 2, 2018
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  10. CC268

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    :yeahthat: Whatever he said :p
     
  11. Mtns2Skies

    Mtns2Skies Super Moderator Management Council Member

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    Thank you - so follow up questions... About what would the cheapest remote DME transceiver be?
     
  12. bnt83

    bnt83 Final Approach

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    IDK, never bought one and never plan on it :p
     
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  13. flyingron

    flyingron Touchdown! Greaser!

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    And the SL30 can not be "used as a DME" either.
     
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  14. CC268

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    GNC255 is the best radio ever doe
     
  15. Axtel4

    Axtel4 Pre-takeoff checklist

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    The only remote GA DME options are the KN-63 ($10k) and the KDM-706/706A (upper 5 digits).
     
  16. Mtns2Skies

    Mtns2Skies Super Moderator Management Council Member

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    Thanks! I'll stay DME-less :) one less antenna anyway.
     
  17. flyingron

    flyingron Touchdown! Greaser!

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    But in addition to those, many of the panel mounts (like the ubiquitous KN62 and KN64) can be remotely channeled. You put the switch on it in "RMT" and it follows whatever radio it's connected to.
     
  18. arnoha

    arnoha Cleared for Takeoff

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    For nearly all approaches, it's legal to substitute a GPS navigator for a DME. It's not a DME, but it will replace one legally in nearly all situations.