Garmin Hypothetical: GTX345 Feed Low Cost Navigator

Sinistar

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Brad
Okay, I think our avionics shop has just finished up installing the GTX345. We went back and forth on having it all in one (GNX375) or separates (eg. 345+???) and decided to just do the GTX345 for now and wait a bit for navigator options.

So my hypothetical: Lets say Garmin were to announce a lower cost GPS+GTR like hybrid. A single COM radio but not a NAV so it could do GPS RNAV but not VOR/ILS. There are a lot of us out here with GTX345 (for ADSBout compliance), older radios but no RNAV capability. It makes me wonder if they could keep the price of this mythical magic unicorn box down even more by taking the GPS out of the GTX345. So it would be different than that GPS175 (have a COM) but not as capable as a 430/530/650/etc.

So the question: Can a GTX345 feed GPS out to actual navigation devices vs the tablets and the Aera displays? This question is not about the GTX345 feeding ADBSin wx and traffic - I am aware of it feeding more devices with that data. This is about it being a GPS source for a navigator.
 
So the question: Can a GTX345 feed GPS out to actual navigation devices vs the tablets and the Aera displays? This question is not about the GTX345 feeding ADBSin wx and traffic - I am aware of it feeding more devices with that data. This is about it being a GPS source for a navigator.
Looking at the (admittedly crude) interface block diagram in the GTX3x5 maintenance manual, it would appear to be no. I don't see a wired output for position.
 
The GTX345 w/WAAS (not all GTX345's have the GPS receiver onboard) can provide WAAS position source to G5's for at attitude aiding, but no, it cannot provide a navigational position source.
 
The GTX345 w/WAAS (not all GTX345's have the GPS receiver onboard) can provide WAAS position source to G5's for at attitude aiding, but no, it cannot provide a navigational position source.
Thanks. There goes my magical mythical low cost Navigator Radio thingy...it would also need its own WAAS GPS.
 
Thanks. There goes my magical mythical low cost Navigator Radio thingy...it would also need its own WAAS GPS.
Frankly, just a WAAS GPS receiver by itself is not really a high cost item.
 
I’m hoping for an updated Garmin GPS/Com GNC 250XL replacement. Please Garmin! (edited to change model number. I actually have a 250XL that needs replacing)
 
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Why isn't there a remote mounted GPS LRU that ties to navigators/transponders/etc via CANbus?
 
Why isn't there a remote mounted GPS LRU that ties to navigators/transponders/etc via CANbus?
Somebody not thinking far enough ahead? Or maybe too far ahead?
 
They heard me! Thanks so much Asicer.

Hoping it will be a drop in replacement of my GNC 250 XL and will be able to ‘talk’ to my Tru-trak autopilot just like the GNC250 does. I’m S-LSA, so the paperwork will be easy.

Kent
LOL. We're talking Garmin here silly wabbit, of course it will not be slide in replacement to anything.
 
LOL. We're talking Garmin here silly wabbit, of course it will not be slide in replacement to anything.

The form factor is the same as the King KLN 89/89B/90/94 series, the Apollo GX50/55/60/65 series, the Garmin GNC 250XL, etc... So which one do you make it a slide in replacement for?
 
The form factor is the same as the King KLN 89/89B/90/94 series, the Apollo GX50/55/60/65 series, the Garmin GNC 250XL, etc... So which one do you make it a slide in replacement for?

He was responding to my hope that it would be a slide in replacement for a Garmin 250XL.

Talked to Garmin today and they said it does require a new tray and cables. And that it’s likely not compatible with my Trutrak autopilot, sadly.
 
The form factor is the same as the King KLN 89/89B/90/94 series, the Apollo GX50/55/60/65 series, the Garmin GNC 250XL, etc... So which one do you make it a slide in replacement for?
hell, "any" would be an improvement for Garmin. Has garmin ever launched a nav or gps product that fits that criteria? they wont even do it for their own customer base for christ sake. to be fair, the stockholm syndrome among that customer base is high, so why give an inch am i right? At any rate, Avidyne was absolutely brilliant by going 430/530 pin and tray slide in compatible.
 
He was responding to my hope that it would be a slide in replacement for a Garmin 250XL.

Talked to Garmin today and they said it does require a new tray and cables. And that it’s likely not compatible with my Trutrak autopilot, sadly.

Most of the newer stuff requires the higher quality coax to the newer GPS antenna. Lower loss and LNA in the antenna I believe.

I don’t think they could have made it a slide in replacement.
 
Most of the newer stuff requires the higher quality coax to the newer GPS antenna. Lower loss and LNA in the antenna I believe. I don’t think they could have made it a slide in replacement.

Not to debate Nate, but, I think slide in replacement means that tray, back plate, and connectors are the same. Coax wouldn't be part of that.

Case in point, sending 430 out for the 430W upgrade, it came back "slide in" but 1 plane needed new(er) coax and the other didn't. Both needed the new antenna (of course). Installation charges were predictably different :(
 
Okay, I think our avionics shop has just finished up installing the GTX345. We went back and forth on having it all in one (GNX375) or separates (eg. 345+???) and decided to just do the GTX345 for now and wait a bit for navigator options.

So my hypothetical: Lets say Garmin were to announce a lower cost GPS+GTR like hybrid. A single COM radio but not a NAV so it could do GPS RNAV but not VOR/ILS. There are a lot of us out here with GTX345 (for ADSBout compliance), older radios but no RNAV capability. It makes me wonder if they could keep the price of this mythical magic unicorn box down even more by taking the GPS out of the GTX345. So it would be different than that GPS175 (have a COM) but not as capable as a 430/530/650/etc.

So the question: Can a GTX345 feed GPS out to actual navigation devices vs the tablets and the Aera displays? This question is not about the GTX345 feeding ADBSin wx and traffic - I am aware of it feeding more devices with that data. This is about it being a GPS source for a navigator.

Garmin released a product yesterday that matches your description.
 
I’m hoping for an updated Garmin GPS/Com GNC 250XL replacement. Please Garmin! (edited to change model number. I actually have a 250XL that needs replacing)
I have a perfectly functioning GNC250XL with two cards updated last year with East and West USA. If you are interested in it, just send me a message. They are great units! Great for GPS backup and a great second Comm!
 
Not to debate Nate, but, I think slide in replacement means that tray, back plate, and connectors are the same. Coax wouldn't be part of that.

Case in point, sending 430 out for the 430W upgrade, it came back "slide in" but 1 plane needed new(er) coax and the other didn't. Both needed the new antenna (of course). Installation charges were predictably different :(

Actually that’s kinda what I meant. The stuff goes in as an approved “system” including coax and antenna, so worrying about a tray slide in usually doesn’t help more than one AMU on the install that still has to go to a shop. :)
 
When the inevitable happens and my 430W goes Tango Uniform I'm gonna slide in the IFD440. That should be a true slide in replacement. And if I'm at all lucky the IFD440's will be available used!

Fingers == crossed :)
 
Garmin released a product yesterday that matches your description.
Let's just say I might have already known :) ..but wasn't sure if the GTX 345 would play a role like feeding its GPS source (which has already been answered, no).

Do you want to know the winning lottery numbers now :)
 
Let's just say I might have already known :) ..but wasn't sure if the GTX 345 would play a role like feeding its GPS source (which has already been answered, no).

Do you want to know the winning lottery numbers now :)
Let us know when they start selling a unit with GPS and NAV but no COM. :)
 
Why isn't there a remote mounted GPS LRU that ties to navigators/transponders/etc via CANbus?

You mean like the Trig TN70 position sensor for ADS-B?
 
the gps reciever hardware is cheap. the cost comes in the data base, screens and drivers and other goodies to meet the TSO. I do not know what chip set garmin is using but the new maxim 2769 gnss chip is only about 10 bucks in small quantities.
 
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The GNC 355 being 2k more than the GPS175 seems a bit tough to swallow an extra $2k for basically a com board.
 
The GNC 355 being 2k more than the GPS175 seems a bit tough to swallow an extra $2k for basically a com board.
For when you just gotta have COM3 to monitor guard and don't have space for yet another radio?
 
Most audio panels do not support 3 coms

But, a fair number of popular ones do. Garmin GMA340, GMA347, the G1000 audio panel, PS Engineering PMA7000 series, etc.

PS Engineering even has one that supports 8 Com radios! Not something that your average privately owned airplane is going to have, though. ;)
 
That's still a small fraction of the price of a new radio. :(
I figured a GTR225 installed is around $2500. So paying $2k more for the 355 vs 175 isn't that far off. I like it because my 2nd KX155 needs to go but I don't want to use that space again so the COM being in the navigator is nice for space. I could also see it being my primary radio if the airport info on the screen helps simplify the radio station selections via the GPS info already on board.
 
I don't see any ADSB-out indicated in the transponder...did I miss something?
Their website shows a second box for ADS-B. I guess it's something like a GDL-82.
 
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