Multiple Sources Driving Shared CDI/HSI

Sinistar

Sinistar

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Brad
Maybe some here can help. If a person installs a new Garmin GNX375, dual G5s and a GNC 255 can the 375 navigator and the navcom share the 2nd G5 as HSI via some kind of switch?

Related question: could this same 375 and same navcom both drive a single 106b with some type of switch?

Both questions would be certificated airplane and for legal IFR.
 
The G5 is certified to serve as HSI for 2 different sources without a switch. It can’t be connected to a third party auto pilot in this case, though, as I understand it. The GAD29b has this capability.

You can have a Nav radio and GPS drive a single indicator, like a 106A, with a special switch. The switch has to switch about 20 wires.
 
There is no auto pilot in the mix here. That’s what I thought too ( we were discussing offline, but wanted to make sure). In other words if the said plane needs to fly ILS that 255 needs to be connected to something like a 106b
 
Thanks @Jesse Saint ! @WannFly and myself have been trying to help a friend understand his quote and how his 375 and 255 navcom would drive his equipment. So were guessing the installer will connect the 375 to the 2nd G5. I just learned that he has a old ki-214 (that was fed by a 170b) ...can his new 255 navcom reuse the ki-214?

Where do I send the beer money :)
 
You can connect the 255 and 375 both to the G5 HSI via the GAD29.
 
Sinistar said:
Thanks @Jesse Saint ! @WannFly and myself have been trying to help a friend understand his quote and how his 375 and 255 navcom would drive his equipment. So were guessing the installer will connect the 375 to the 2nd G5. I just learned that he has a old ki-214 (that was fed by a 170b) ...can his new 255 navcom reuse the ki-214?

Where do I send the beer money :)
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I didn’t give any useful answer but I would take the beer money
 
But you can also see two sources at the same time. You just get two lines of different types.
 
Interesting that you can see both sources at the same time!

A follow up. It turns out the GAD29 was missing from my friend's quote sheet but was priced in and confirmed. So he is good to go. I'll pass on the part about seeing both.

My other question was whether the 255 navcom could feed his KI-214 but from reading up on it it sounds like the GS is built right into the KI-214 so I doubt the new navcom could feed it anyway.
 
Sinistar said:
Interesting that you can see both sources at the same time!

A follow up. It turns out the GAD29 was missing from my friend's quote sheet but was priced in and confirmed. So he is good to go. I'll pass on the part about seeing both.

My other question was whether the 255 navcom could feed his KI-214 but from reading up on it it sounds like the GS is built right into the KI-214 so I doubt the new navcom could feed it anyway.
Click to expand...

G5 STC explicitly does not allow a CDI attached to any nav source interfaced to the G5 (if that’s what you meant...) and if you just meant connecting it by itself, it’s not listed in the 255 manual, but a cursory glance at the 214 pin out, looks like it in additional to having its own GS receiver when connected to something that can drive it’s channeling, it has pins for +/- GS flag and up/down and a composite input so potentially could be connected similar to a 209.
 
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And that switching relay to drive a single analog head from GPS or Nav is outrageously expensive, at least for 14v systems. You can find 28v units dirt cheap all over the place.
 
Jesse Saint said:
You can connect the 255 and 375 both to the G5 HSI via the GAD29.
Click to expand...

Nice! I need to replace my #2, a failing Terra Nav/Com (the LED displays are going)...looks like the Garmin 255 is a logical replacement, and I should be able to hook up both my GNS-430 and Garmin 255 to the G5s? That would mean I could avoid re-installing my GI-106A?
 
chemgeek said:
Nice! I need to replace my #2, a failing Terra Nav/Com (the LED displays are going)...looks like the Garmin 255 is a logical replacement, and I should be able to hook up both my GNS-430 and Garmin 255 to the G5s? That would mean I could avoid re-installing my GI-106A?
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Yup. I chose to keep mine just for redundancy. If the G5 craps out (I know, unlikely) I'll still have VOR.
 
I'm installing the GNC 355 with a second G5 after the first of the year. (first G5 replaced the AI) I have an SL30 with a CDI. The shop wants to know if I want the 355 and the SL30 to talk to the second G5. Absolutely not! I like and want the redundancy of a completely separate nav/com from the gps/com.
 
murphey said:
I'm installing the GNC 355 with a second G5 after the first of the year. (first G5 replaced the AI) I have an SL30 with a CDI. The shop wants to know if I want the 355 and the SL30 to talk to the second G5. Absolutely not! I like and want the redundancy of a completely separate nav/com from the gps/com.
Click to expand...
This is exactly what I did. I love it.
 
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