uAvionix EchoUAT/SkyFyx (generic) interface to GRT HX?

[rv7charlie]

Well, during a brain lock session, I ordered (and received, unboxed, and mounted) a generic uAvionix EchoUAT with their SkyFyx GPS, instead of the GRT-specific package with the SafeFly2020/serial expander. Unfortunately, I find no docs anywhere that tell me whether my GRT HX can have any control over the Echo (specifically, setting anonymous mode), nor how to wire it/configure it.

So far, I'm at gnd & pwer on pins 1 & 2 of the Echo, and traffic out of the Echo via com2 out (pin 5) to a high speed port of choice on the HX. (Plain Vanilla for feeding traffic to an EFIS)

Can the HX communicate/control the Echo via either com1, or the available com2 in on the Echo?

Config settings in the HX for one or both ports?

I've been trying uAvionix, but they seem to be quite busy at the moment.

Thanks,

Charlie

[GRT_Jeff]

The only official way to change anonymous mode is through the echo app so there's no disadvantage for that.

Your ADS-B In wiring sounds correct. Configure the EFIS input for 115200 and ADS-B.

The EFIS can't send anything directly to the echoUAT except altitude. The echo still needs to get squawk by listening to the transponder replies so there's not a big advantage to wiring that up.

The main control the HX has is the Flight ID, but you would need a Safe-Fly for that. The HX doesn't have a built-in TMAP interface. You'll have to change that in the app if you ever need to.

[rv7charlie]

Who'da thunk I'd be frustrated by simplicity.

Many thanks; I'll get it up and running tomorrow.

[JimB]

I'm trying to assist someone with a echoUAT and SkyFyx. He has a single GRT Sport SX EFIS and a GTX330 (not ES) transpoder. The transponder is new to him but I think echoUAT can't "sniff" a Mode S transponder. Is that correct?

The above threads state that there is no interface from GRT to echoUAT.

But the echoUAT install manual paragraph 5.3 Interfaces states Com 1, Setup/Mode/Altitude?Squawk/Ident/GPS Position Devices include GRT. Com 2 RX GPS Position Device includes GRT. Com 2 TX ADSB Traffic & ADSB Uplink Devices includes GRT.

Later in paragraph 7.5 Pin Assignments show Com 1 TX RS232 38400 baud TMAP protocol, Com 1 RX RS232 38400 baud TMAP protocal and Com 2 TX RS232 115200 baud GDL 90 protocol and Com 2 RX RS232 115200 baud NMEA protocol.

Further paragraph 8.3.1 shows setting up the echoUAT with TMAP protocol.

And their interconnect diagrams show GRT.

Is the problem that GRT doesnt support TMAP protocol? Is there a converter for that? Or some work around?

Thanks

Jim Butcher

[GRT_Jeff]

They can't sniff some of the information from a Mode S transponder like the 330, squawk or altitude or both.

Our TMAP interface for the echoUAT is only available through our Safe-Fly GPS serial control interface. The other TMAP interface we have is for transponders (that one uses an adapter on an HX). The EFIS can send its altitude data to the Safe-Fly GPS, and then the Safe-Fly GPS can send the altitude data and (optionally) GPS data to the echoUAT. It's also possible for the EFIS to read squawk from a 330 REMOTE+TIS serial connection and send it through the Safe-Fly with TMAP.

There are (or used to be) mux adapters made by uAvionix for the echoUAT so you could use a serial altitude source (from an EFIS) and combine that with the 330 REMOTE squawk data to get it into the echo. That was their standard way to connect a 330 before the echoALT. It may be possible to connect the 330 REMOTE to COM1 for squawk and an echoALT for altitude since then.

[JimB]

Thanks Jeff!

Right now the guys are using the Gray Code (8 wire) connection on the Sport to supply altitude info to GTX330. Is there any advantage to using a serial port (air fuel Z format) instead of Gray Code?

BTW, there are several threads on VAFof success using Mode S transponders with EchoUAT.

Thanks for all the assistance.

Jim Butcher

[GRT_Jeff]

The Fuel/Air Data output includes airspeeds that can be used for automatic mode changes or flight timers, so that can be an advantage. The serial data is higher resolution (25 ft vs 100 ft) but I don't think that does anything for you.

Mode S transponders used to work fine but the FAA started removing an extra signal that made them compatible when updating radar equipment after 2021. It may still partially work in some locations or depending on other factors, but as far as I know you can't count on it working reliably.

[JimB]

Jeff,

One last question. I've read the Safe Fly manual thru and there is a section about controlling echoUAT with GRT EFIS by way of Safe Fly.

I think this is what you were talking about in the previous mesage " The EFIS can send its altitude data to the Safe-Fly GPS, and then the Safe-Fly GPS can send the altitude data and (optionally) GPS data to the echoUAT. It's also possible for the EFIS to read squawk from a 330 REMOTE+TIS serial connection and send it through the Safe-Fly with TMAP." In this scheme you would set squawk code on GTX330. Altitude and squawk would be sent to echoUAT via Safe Fly. Would this mean echoALT isnt needed since echoUAT isnt trying to sniff altitude and squawk from the transponder?

Thanks,

Jim Butcher

[GRT_Jeff]

Yes, that is describing the EFIS TMAP interface through the Safe-Fly control interface. The EFIS always send altitude through that interface. uAvionix support has said systems that are already working that way don't really need the echoALT, although they were pushing it for everyone originally. The echoALT only does altitude, not squawk. The EFIS can push squawk through the same interface if it can get the squawk, and the 330 includes the squawk in the older TIS-A serial traffic data. We added a "Copy GTX Squawk" function for that. If the EFIS is pushing the altitude and squawk through then you don't need a mux either.