What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Wiring echoUAT to GTX327

Trying to wire the echoUAT to my GTX327. However my GTX327 RS-232 out (pin 20) is already wired to my Garmin430W (pin 57). Contacted uAvionics and they said unfortunately the 327 has only one RS-232 out. So you can?t hardwire it and must use the non wired method- interrogation replies through the aircraft electrical system. I would like to hardwire it if at all possible. Does anyone know if I can tap off the GTX-327 RS-232 output wire (pin 20) for the echoUAT?
Other suggestions?

Thanks
 
I?m not 100% sure but I think you can split off RS-232 by splicing in another wire and share the signal. Might be worth asking someone more knowledgeable.
 
Trying to wire the echoUAT to my GTX327. However my GTX327 RS-232 out (pin 20) is already wired to my Garmin430W (pin 57). Contacted uAvionics and they said unfortunately the 327 has only one RS-232 out. So you can’t hardwire it and must use the non wired method- interrogation replies through the aircraft electrical system. I would like to hardwire it if at all possible. Does anyone know if I can tap off the GTX-327 RS-232 output wire (pin 20) for the echoUAT?
Other suggestions?

Thanks

I have the same equipment and they told me the same thing. I went with the non-wired method. Works great. The settings do require some adjustments to get it right. Not sure why they don’t just publish it on their website.
 
In general, splitting one RS-232 output across a few inputs works without issue. Going the other way (multiple outputs connected to a single input) does not work; you need a mux to digitally combine the input streams.

It is possible to hard-wire a serial encoder and a GTX-327 to the echoUAT to avoid "sniffing" the pulses over the 12V system; I did it on my -7A. However, this isn't as straightforward as just splitting off an extra RS-232 line from Pin 20.

The RS-232 Out pin on the 327 can be configured to output either pressure altitude ("ICARUS ALT"), or squawk code / ident status ("REMOTE"), but not both simultaneously. The problem is that echoUAT requires both.

If you do have a serial encoder, there is a workaround. This requires ordering a (free) GNS mux harness from uAvionix support:
  • Encoder serial output should be 9600 bps, Icarus / Garmin format
  • Keep the existing connection between your encoder and GTX327 (either Pin 19 RS-232 input, or Gillham code; either will work)
  • Connect GNS430W pin 57 directly to an RS-232 output on your encoder (splice as needed)
  • Connect GNS mux pin 3 directly to an RS-232 output on your encoder (splice as needed)
  • Connect GTX327 Pin 20 to GNS mux pin 1, and reconfigure the OUT mode from "ICARUS ALT" to "REMOTE"

The uAvionix mux harness has an IC that digitally combines the 9600 bps pressure altitude and GTX327 control streams from Pin 1 and Pin 3 of the adapter. Output is passed at 115200 bps to Pin 4 (COM1) of the echoUAT Molex connector.

If you have a Gillham-only encoder, you're out of luck; there's no way to get an RS232 altitude data stream for the echoUAT and the transponder control stream at the same time.
 
Keith, thanks for the info. Really helpful. I?ll contact uAvionics for the GNS mux harness.

Jerry glad to hear the ?sniffing? method works. I may end going that way if I can?t get the mux harness to work.
 
This is good timing since I am about to install my Echo as well. I have the GTX330 which has two outputs. Currently the skyview is providing the Alt data. The transponder is also connected back to the EFIS for status (remote). I have the Mux unit already. Plan is to connect the efis out (Altitude) and 330 out (Remote) to the Echo Mux. I am mounting the Echo and antenna in the wing access panel. GPS antenna is inside the wingtip.
 
wire it - don't need to

I hope that I'm not misunderstanding the OP but the Echo UAT from uAvionix does not need to be wired to the GTX327.

I have both. I have NO wires connecting the UAT to anything except:
Power
Ground
GPS antenna (not actually part of the Echo)
ADS-B TED antenna

The device auto-magically is aware of what your transponder is doing and behaves in coordination with it. I am using non-tech terms because I have no clue how this is done. I only know that it works well.

I have a copy from an avionics shop that used their compliance tool on mine. My problem is reported in my recent thread but it has nothing to do with my transponder.
 
I have the same equipment and they told me the same thing. I went with the non-wired method. Works great. The settings do require some adjustments to get it right. Not sure why they don?t just publish it on their website.

Could someone clarify the "non-wired" method?

I have a 327 and a GTN 650 and my rs232 out from my transponder is already talking to my 650.

I am guessing that the non-wired method is a software configuration on the app for the echo? Is that correct?

:confused: CJ
 
Could someone clarify the "non-wired" method?

I have a 327 and a GTN 650 and my rs232 out from my transponder is already talking to my 650.

I am guessing that the non-wired method is a software configuration on the app for the echo? Is that correct?

:confused: CJ

The Echo "sniffs" the transponder squawk code and altitude information from the transponder output when the transponder is polled by radar and replies. Thus wireless. The Echo does require a hard-wired GPS signal from a WAAS GPS.
 
Could someone clarify the "non-wired" method?
I am guessing that the non-wired method is a software configuration on the app for the echo? Is that correct?

:confused: CJ

Yes. The software configuration setup will determine how the transceiver obtains the transponder code, wireless or wired.
 
I have the same equipment and they told me the same thing. I went with the non-wired method. Works great. The settings do require some adjustments to get it right. Not sure why they don’t just publish it on their website.

Jerry, please share EACH configuration setting you are using. I too have the EchoUAT that is suppose to be sniffing my 327 transponder. Ive been trying to dial it in since it was installed in July 2018 (16 months ago). Anyone else please also share your working settings.

Need help!
Robert
schapler at msn dot c_ _
 
Last edited:
I'll go to the hangar later and connect the app to the device and take a screenshot of the settings. Also, try giving the UAvionix people a call. They were very helpful. Although, I'm not sure why they don't just publish the information. Apparently setting adjustments when sniffing the 327 are very common and almost always necessary.
 
Last edited:
I'll go to the hangar later and connect the app to the device and take a screenshot of the settings. Also, try giving the UAvionix people a call. They were very helpful. Although, I'm not sure why they don't just publish the information. Apparently setting adjustments when sniffing the 327 are very common and almost always necessary.
I need this info too. Thank you.
 
I've spoken twice with the uAvonix support people. They are indeed very nice but the first time I was told settings that didn't work and when I checked with the shop that installed the unit was told they were incorrect. The second time the person was again very nice but I couldn't answer his questions or impliment his instructions because I'm a techno-idiot and therefore couldn't get what he was saying or intelligently answer his questions. I agree, the settings should be included in the installation manual....

Thanks in advance for getting me this information. A screen shot each settings page will be very helpful and very, very appreciated. Please include the advanced settings you can only access by the two finger click on the uAvonix icon.

Robert
 
Last edited:
In retrospect setting up the ECHO to sniff the outgoing 327 pulse (vice hard-wiring) was quite easy but I went through a period of frustration looking for answers. Having followed all the guidance I could find, nothing resulted in a perfect FAA Performance Report. At one point I received a letter from the FAA giving me 45 days to get things right. I thought that I had until January 2020 to get it working, but apparently not. I'm based just outside of the DC SFRA so maybe my proximity opened my transmission to a bit more scrutiny.

Anyway, if someone doesn't beat me to it I'll be happy to post my settings. At Oshkosh 2019 I talked to the uAVIONIX folks at length about getting my setup working with the Garmin GTX327. The easiest way to tell if it's working is to "MONITOR" using the uAVIONIX APP while in flight to ensure that you can read your transponder code. At first that field was blank, and the resulting FAA Performance Reports cited a consistent MODE 3A error. In the end, all I had to do was lower the threshold by using the advanced section of the App. As someone mentioned, you must use two fingers on the App Title to open up that particular page. They'll tell you to lower your threshold by 50 units at a time until you can read the transponder code. In frustration I finally lowered the setting down to 1100 if I remember correctly and all of a sudden things worked and I received a perfect FAA performance report.

I would call the uAVIONIX folks. They were extremely helpful. At Oshkosh they volunteered to take their test set out to the airplane to help dial things in, but unfortunately I did not fly to the event.
 
My EchoUAT Configuration

Gu6-nhxxTR_E7Q0bGSZJKbVUZn5s00iL9IPDI3QPyoD2e8AjdXr6r9cEZhy5I048i32e2QOIS4IK5MuH1xqFaa018cOIvnJrrwwnwSicmxohPnOAM7yzSecAaP4cAbwlumHKqUSsIN_ZFkmLDwoZz2CqZjXR_-4z1aL2B-jrNWGyZlJ3srCvkRw3y6zOZaY5jT-McxBNepe-uEUnkSEENFi0shLtR6Klns_ef-6A2zUdN2lzuKNBcxZ--gAMDqSs-vyUqtEunYsD_NGKApW7DUk0-W7pqn7ZXSpzJthmq0U-JX-jIbc7UprptBpwxRd1ze3Tmn109Z_PzEjuDaLAKD69j3YHthBhbw1uWX94BbX9Sz5ng1nEBKy4smsGSLGsw-eVq7MB2h6rWDVBq6le1CKJJpdk9PmWBvtZ2WlSsTR8dZ9vobciL0fujWYK_h9arSAGLAMQJA8gsVhULMmnJjxRzqIbwxPoHBBl5kOTRUmOlmsivMK0bXKnZyF4I8kv7OQi-Fs6dWaKigsZSbzQG6azZqFiAdiFEr8-ZlyjTjdUdVVzf1WLie0C9guX6iENdfi0EE5J8u4jLTAdWuMEUR8TH05DLkNELstb7NOuxWxU0P33ppb6pxMSNwQTSTppTaMAodRwE8d5yLEDX6TQFyXw4gTjaHzWYTWEVfq7nbKuGGbC0C2hfVdk-F-mfGOe426p1ZnVErvmTozoe33rBKP0NTUf-X8suKcwF4mX9pCaX8JZmA=w300-no



-RFJOCGBr_tt27tpKWvvu1odVpS9QwMynjlK2wsiC7TLg-ZViNP4IU1GS42fvbUcHS0b3eNiGKjdSgk8iYR3NaS8q48h7h0U0RAK-tBa2ATz135yLl9ciaFOnTMb7kLH8mqXSR4pIA7HvN9YAZt3_0D4FQAHhPMXLCoKk7vEF2MvK_ItmF1HYb7rL0VWaLlB4C3PShXHKaKxz2Holl3N4vCMdCWwuEgczgixVCq84qtFnp-nXBJFsBpHI2e7NSzJkzPZ1D01sBI4SLEpa5qh05D3VAk4bVGX-rCI1T01b5lrUhCUd6sCI6OrCQGoCSX-DcBem8vdMs3xDFAXrSUJ8r9tP6xhDOs-KC692b0rsLiRFSNHhRZz9MPcLDVeBzoV2UiuwoblP9dFUdtrTco2ECHg3YKKX1vXthp8tqAKvZB9BxfhVYdHaQxSLkzUdQos6I0Ti686Gc6bVgurbu74gpdAqD4FXCh4Be8JFLboYNx-2CWs0RG3JmY7Qj2lDNhqsqC8o9qhaf9RY4A53fvtR5kupVGmv861M3NOj_8SycHBRGCd_xf7NkTd1LCPNSwCPDFRHC1RF3pKXsyinHVffsQpY_sYhyyWnNBHf6ApdSb2ex0st4PFKc9HoJe9fONUWhTXSaXSi0muHsP_DXRlTLFqFo8qUvySK1-mBjXuVY0hJcZhivADwNTKd8w8wNCXCykI4QCGzaMXbremgqjCPmzoaGIF_ru94R4V_xtsBs7t2mU5mQ=w300-no
 
I would encourage anyone who desires to hardwire their Echo to their GTX transponder to try wireless first. It works great and doesn't require the complexity and hoop jumping the hardwire route takes. In other words treat an echo install with a GTX the same as pairing with any other legacy transponder installation. Do it wireless.
 
EchoUAT w/SKYFY-EXT, ForeFlight GPS Accuracy Question

Quick question....

GPS Accuracy....what are y'all showing as GPS Accuracy using the EchoUAT on the ForeFlight HUD Display bar? I am showing 30 Meters. But when I use the Stratus 2S, I show 1 Meter accuracy on the ForeFlight HUD display bar. Should the EchoUAT give me 1 Meter accuracy as well??

My setup is on an RV-7A, EchoUAT w/ the SkyFyx-EXT, Garmin GTX-330 transponder.

It took me 3 flights to get Transponder Threshold setting dialed in...finally got a good FAA ADS-B Performance report at 1150 as the Transponder Threshold setting.

R,
Dan
 
Quick question....

GPS Accuracy....what are y'all showing as GPS Accuracy using the EchoUAT on the ForeFlight HUD Display bar? I am showing 30 Meters. But when I use the Stratus 2S, I show 1 Meter accuracy on the ForeFlight HUD display bar. Should the EchoUAT give me 1 Meter accuracy as well??

My setup is on an RV-7A, EchoUAT w/ the SkyFyx-EXT, Garmin GTX-330 transponder.

It took me 3 flights to get Transponder Threshold setting dialed in...finally got a good FAA ADS-B Performance report at 1150 as the Transponder Threshold setting.

R,
Dan

The Echo output doesn't include GPS position information, so the GPS position accuracy you are seeing in ForeFlight is coming from either the iPad internal GPS if you have a wifi+cellular version, or an external source such as a Bad Elf via bluetooth if your iPad is wifi only. On the other hand, the Stratus data stream does include GPS information, which could explain the difference.
 
echoUAT + SKYFYX-ext and Garmin GTX327

My combination:
echoUAT + SKYFYX-ext and Garmin GTX327

Can someone tell the pros and cons to hard wire vs. "sniffing" installation.
 
The Echo output doesn't include GPS position information

Where do you find this information Lars?

I have a wifi only ipad (No GPS, Badelf or otherwise) and my Echo output (Wifi SSD: PingXXXX) displays position on my Foreflight. Sometimes 30 meters, sometimes 1m... Never really thought much about where it came from until your post.

Can someone tell the pros and cons to hard wire vs. "sniffing" installation.

This may or may not be related to the sniffing versus hardwiring... Mine's set up as a sniffer and a lot of times when going from VFR squawk to picking up a squawk code like flight following, controllers will ask me if I have 2 transponders. Or they ask how many RV's are in my Flight :) I think it's the lag in which it takes the sniffing to figure out that I've changed squawk codes or something. Not too sure, I hope someone can elaborate here on the technical side.
 
Last edited:
echoUAT + SKYFYX-ext and Garmin GTX327

Thanks Justin.

My combination:
echoUAT + SKYFYX-ext and Garmin GTX327

Still looking for pros and cons to hard wire vs. "sniffing" installation. In my case GTX327 RS-232 out (pin# 20) is available.
 
Reliability

Can someone tell the pros and cons to hard wire vs. "sniffing" installation.

Hard wired should be reliable 100% of the time. The sniffing is looking for a very small voltage in your aircraft wiring which is the transponder output ( pressure altitude and squawk code). It would seem, the threshold adjustment some have needed to perform, is in a effort to find and interpret this . So direct wired from transponder to echo is best IMHO. I have a KT76A, no can do or I would. This is what I was told by Dave ECHOUAT support.
 
Reliability

Thanks Butch. 100% reliability is good - however I can't believe that "sniffing" technology can't be too much away from hard wiring either when you get settings correct.
 
Where do you find this information Lars?

I have a wifi only ipad (No GPS, Badelf or otherwise) and my Echo output (Wifi SSD: PingXXXX) displays position on my Foreflight. Sometimes 30 meters, sometimes 1m... Never really thought much about where it came from until your post.



This may or may not be related to the sniffing versus hardwiring... Mine's set up as a sniffer and a lot of times when going from VFR squawk to picking up a squawk code like flight following, controllers will ask me if I have 2 transponders. Or they ask how many RV's are in my Flight :) I think it's the lag in which it takes the sniffing to figure out that I've changed squawk codes or something. Not too sure, I hope someone can elaborate here on the technical side.

I contacted uAvionix and ForeFlight directly. Both confirmed that there is no position info in the Echo data stream. I had worked on an RV installation where the owner insisted that he was getting some sort of wildly varying position info on his wifi only iPad, similar to what you report. Not sure what's going on, but I wouldn't rely on the position info you are seeing.
 
D100, GTX 327, ECHO and SKY-FYX ETX is my combo

I am 90% done with this installation. It's that last 10% which seems to take forever. uAvionix didn't include my mux cable despite the request. While I wait for its arrival I'd appreciate some feedback on my understanding.

The D100 is set for FORMAT 4, Icarus. GTX327 CHNL 1 has to be set to ICARUS ALT because that?s the format of the data coming coming in from the D100 Alt Enc.

The D100 sends out Alt Enc data using Pin 13 of its DB25 to GTX 327 Pin 19.

If you want ICARUS ALT data to go out on GTX Pin 20 to the ECHO, set GTX output for ICARUS ALT.

If you want the GTX OUTPUT on Pin 20 to send ?squawk code / ident status?, set GTX OUTPUT ="REMOTE".

The GTX 327 has only one output (Pin 20). ICARUS ALT data can be sent to the ECHO two ways, either via sniffing or via the Mux cable. Squawk/ident info cannot arrive at the ECHO via sniffing so it must be sent out via Pin 20 on the GTX.

Until my MUX cable arrives, set output on the GTX327 to REMOTE so that Squawk arrives via wiring and rely upon sniffing to send ICARUS ALT data to the ECHO.

The Mux cable is the preferable method because it is more reliable.

Comments welcome. Thx.
 
D100, GTX 327, ECHO and SKY-FYX ETX is my combo

I am 90% done with this installation. It's that last 10% which seems to take forever. uAvionix didn't include my mux cable despite the request. While I wait for its arrival I'd appreciate some feedback on my understanding.

The D100 is set for FORMAT 4, Icarus. GTX327 CHNL 1 has to be set to ICARUS ALT because that?s the format of the data coming coming in from the D100 Alt Enc.

The D100 sends out Alt Enc data using Pin 13 of its DB25 to GTX 327 Pin 19.

If you want ICARUS ALT data to go out on GTX Pin 20 to the ECHO, set GTX output for ICARUS ALT.

If you want ?squawk code / ident status? to go out on GTX Pin 20, set GTX OUTPUT ="REMOTE".

The GTX 327 has only one output (Pin 20). ICARUS ALT data can be sent to the ECHO two ways, either via sniffing or via the Mux cable. Squawk/ident info cannot be sent to the ECHO via sniffing so it must be sent out via Pin 20 on the GTX.

Until my MUX cable arrives, set output on the GTX327 to REMOTE so that Squawk arrives via wiring and rely upon sniffing to send ICARUS ALT data to the ECHO.

The Mux cable is the preferable method because it is more reliable.

Comments welcome. Thx.
 
I contacted uAvionix and ForeFlight directly. Both confirmed that there is no position info in the Echo data stream. I had worked on an RV installation where the owner insisted that he was getting some sort of wildly varying position info on his wifi only iPad, similar to what you report. Not sure what's going on, but I wouldn't rely on the position info you are seeing.

That's wild because I was told by uAvionix that I could use a wifi only iPad and it would show my position on WingX and FltPlanGo. Other pilots on threads here say the same thing. I suppose some things you just have to go up and test with your own iPad to get the real scoop.
 
My WiFi only iPad works fine w/iFly when it?s connected to the EchoUAT. The little gps indicator on the iFly system depicts a green vertical bar indicating I?m getting the position through the gps SkyFYX attached to the EchoUAT. I don?t know why it wouldn?t work with any other EFB. YMMV. Bob
 
The Echo output doesn't include GPS position information, so the GPS position accuracy you are seeing in ForeFlight is coming from either the iPad internal GPS if you have a wifi+cellular version, or an external source such as a Bad Elf via bluetooth if your iPad is wifi only. On the other hand, the Stratus data stream does include GPS information, which could explain the difference.

Just now wrapping up my install of the EchoUAT and SkyFyx combo with a Garmin GTX327, I called Uavionx support to get clear information regarding the GPS information.

I spoke with Dave in tech support (also an RV-8 guy on this forum) and he assured me that "absolutely GPS information is broadcast over WIFI to any connected device. GPS position is part of the GDL-90 protocol."

This should put this controversy to bed. If you like, call Dave directly. He'll tell you the same thing.
 
Got ADSB working using sniffing

My 9A setup is Dynon D100, AVARE, Samsung Tablet, AP74, GTX327, echoUAT, SkyFYX-EXT and CMAX bluetooth to serial for the AP74.

On Jan 19,2020, I finally got good PAPR results. Here are my notes which apply ONLY to my combo. I am not an EE but very methodical.

Make sure the GTX327 has the latest software.
Set CHNL1 to ICARUS ALT, output = Remote.
The Samsung Tablet has an internal GPS which would suffice for my VFR flying but not for ADSB. Two GPS sources are available to the Samsung when the Sky-FYX EXT (GPS) was added. I disabled the internal Samsung GPS and that extended the battery. The Samsung finds GPS signals thru WIFI. Set the Samsung WIFI = PINGxxxx before launching Avare I/O.

AVARE has a feature where it can use ALL AVAILABLE GPSs, Internal Only, or AVARE IO Module Only. When using echoUAT WIFI PINGxxxx and SkyFYX-EXT WAAS GPS, set AVARE to ALL AVAILABLE.

Cell phone Bluetooth should be OFF lest the phone might seize CMAX and deny it to AVARE I/O which creates "sentences" for the autopilot. However, two devices (Samsung and my Android cell) accessing PINGxxxx WIFI seems to work. However, WIFI cannot be used by two APPs on the Samsung at the same time (such as ECHO monitor and AVARE I/O). I tried it several times and could not get reliable results but the only task my Samsung has is flight services. I monitor the echo using my cell.

Here is my rudimentary understanding of sniffing and it comes from many Vans contributors to whom I am forever thankful for helping me make sense of this.

SNIFFING EXPLAINED: The power transcoder inside the ECHO detects noise (signals) from the transponder that are induced on the power wires (within the aircraft) during transmission (when pinged by ATC or another plane). ECHO circuity and logic recover that ?noise? and turn it into the squawk and altitude information to feed ADS-B broadcasts. SNIFFING allows a single point of entry for the squawk code and altitude. No wiring is needed.

I must admit, the folks at Uavionix are bloody geniuses having figured this out. All I know is that it works.

Set the D100 Alt Enc to FORMAT 4. The D100 is wired to the GTX327. D100 Pin 13 connects to GTX Pin 19. After changing the GTX as above, Pressure Alt appeared on the GTX screen and also on the ECHO Monitor App running on the cell phone. I was elated, 2 months of work and research finally resulted in Miller Time.

Repeated PAPRs tell me this continues to work so while I have the MUX cable, if it ain't broke, I'm done.

Hope this helps.
 
Garmin sued uAvionix because they were convinced that their patented over the air (RF signal reception) method had been duplicated. That suit quietly went away. The method of picking data off the main bus voltage is sheer genius in my view. Very out of the box thinking. If you research the designers resume and see the TIVO amongst other clever electronics, you will be surprised. full disclosure----my employer sells their products----
Having said that, I prefer RS-232 when possible. The mux serial combiner has allowed that in many cases.
 
GPS data in Echo stream

I have the uAvionics echo installed in both my RV6 (sniffer) and RV7 (mux hard line). In both cases, it drives my wifi-only ipad mini with ownship position. The position itself is derived from the GPS feed it gets from my GNS430W, and is the same as it uses for the ADSB-out messages.

I don't believe it repeats position information out over it's serial output links. Maybe that was the confusion?

It did take me a while to get the software and serial ports configured correctly to work with the MUX and with my EFIS. In my case, in part because I had tried to use one serial port for in and out on the EFIS, but it turns out the IN needed to be at a different speed than the OUT.

These days, though, both are working nominally with the iPAD, and in the RV7, also with the hard wired GRT EFIS.

One other install note is that I went back and wired the echo power supply from the GTX327 switched output so that turning off the transponder also turns off the ADSB (as is helpful when actually in formation). Just a thought to share since I didn't think of it the first time.

I too have noticed the query from ATC about two transponders when picking up flight following. I believe the issue is with the ATC computers understanding (or lack there of) of anonymouse mode. You can configure your echo to use an anonymous ID when squaking 1200. When you pick up a discrete squawk code, it automatically switches to your real mode S code. The ATC computer then concludes there are two airplanes in the same place until the old one "times out". Seems to take about 10 seconds.
 
Heres how I do it

After installing quite a few EchoUAT systems, using TXP Monitor, I use the following method to set up the Transponder Sensitivity.

After all of the App programming is done, I push the plane out of the hangar so I can get a good GPS signal.
Connect the App to the Echo.
Once I get the GPS Altitude, I look to see if Pressure Altitude is being displayed. (If you don't get GPS then you need to get that working first since a report will not generate without the GPS.)
If no Pressure Alt, I crank down the TXP Sensitivity until Pressure Altitude appears on the Monitor page of the App. (I almost always have to crank down the TXP Sensitivity from the preset 1500.)
Once I get both GPS and Pressure altitude to appear (These will probably not be the same) its time for a flight. So far the ADSB reports have always passed using this method.
 
Wiring the echo

SCR said: One other install note is that I went back and wired the echo power supply from the GTX327 switched output so that turning off the transponder also turns off the ADSB.

That's an interesting idea. I put my echo and my CMAX BT to Serial on a separate breaker.

Yes, getting it all to work took a long time but I made conspicuous notes along the way so I didn't have to back track or forget what I did in the future. The biggest roadblock was a crappy BT to Serial I bot. Sometimes it worked, sometimes not. Drove me nuts. The CMAX product has been bulletproof. I use AP all the time so that component was essential. Understanding SNIFFING took a lot of coffee.

Frankly, with ADSB in and out, it's made flying a much more pleasant experience.
 
I have the Echo with a 430 and 327. I am going to do a test flight today. I also had to dial the transponder down to get a pressure altitude reading on the App.
It still goes off and on when just sitting on the ground. I guess ill find out when I fly today if I pass. Its not as easy as I thought and in retrospec I would have done a GDL 82 set up
 
I couldn't agree more. If you want to hard wire an ADS-B out product go with he GDL 82. If you are confident enough to trust sniffing (and you should be) go with the Echo. Street price on the GDL 82 is around $1630 so if you add the MUX and fuss to the Echo you will probably be ahead with the GDL. Then add your "in" of choice. Not knocking the Echo. I fly one in my 3 and would install it again in a heart beat. I have installed 2 other Echos in buddies RVs. I have installed more GDL 82's than anything so far. With the Echo just don't understand all the hardwired fuss when the sniffing works perfectly.
 
Last edited:
I never realized how the "sniffing" worked until I went to start it up. Mine was a real bitch of an install since my F1 has a ton of avionics in it. I learned how to install Garmin pins and how to remove them. I have lots of respect for guys that do it everyday
 
Flew mine today and got the dreaded Baro Failure message on my report, so I'm guessing I'll need to lower the threshold values. I don't mind the little bit of trial and error adjustments.. The install was super easy.
 
Use the monitor app

I lowered mine to 1300 and almost instantly started getting pressure alt showing in the app.

Uavionix advised me to have the App open in monitor mode while flying. Start lowering the threshold number 25/50 at a time until you see the baro alt setting ?populate.? It dropped out briefly after that so I went just a bit lower and it became rock steady.
A really easy way to get that threshold number set right.
 
echoUAT

GRT advised me that uAvionix said to reset Transponder Threshold to 1350 on all units effective in 2020 using Monitor App from uAvionix echo App from play store or Apple store.
 
In post 4 Kieth does a good job explaining why the mux is needed. The unit only has two serial interfaces and one is dedicated to gps input and the other needs pressure altitude and squawk code. The squawk comes from the gtx327 and alt from the encoder, so the mux combines them and sends them on the second interface.

The advantage is that it is dead reliable and more anonymous. I say more anonymous because your transponder might not see interrogations on the ground or in remote areas and when it is silent for a time the echo can’t sniff the alt and squawk so it reverts to spitting out your tail number.

I see this all of the time when flying with my bud near the Canadian border. His skybeacon goes in/out of anonymous mode.

Another thing to point out is that the mux only works with a serial encoder in Icarus mode. If you are sending alt from a G3X it won’t work in that case a GDL 82 is the better option.

For everybody with a serial encoder or a dynon (or GRT which from what I understand can now send the same signal as the mux thus eliminating it) the echo is a great option because it is smaller, cheaper, and provides ADS-b and GPS to a phone or iPad.

Bottom line, if anonymous is important, use the mux and if anonymous is important and you have a G3X, use a gdl82.
 
I use the sniff method for my Echo. . It took a number of trial settings of " threshold" value to find the correct level but once found it has worked fine since. I believe if I remember correctly that threshold setting was 980. Lower than what is usually recommended but seems to work fine . uAvonucs sent me a MUX that I have in the drawer but never found the need to install once Altitude was consistent on ADSB performance report.
 
OK, so after reading multiple threads on the echoUAT, I'm thinking it is probably the way to go in conjunction with my GTX327. I will probably go with the 'sniffing' option because it appears to work well without the wiring complexity.

At first, I was thinking I wanted the skyFYX GPS option (instead of their -EXT version) because it appeared that the antenna was smaller and I'd rather not mount another puck on the exterior of my plane. But now Tech Support at uAvionix is telling me they have discontinued the standard skyFYX GPS option, and only the -EXT version is available. Yes, the option still shows up on their website, but I'm told they're discontinuing it because there is NO advantage to it over the -EXT option.

That said, is there any reason I shouldn't go with the echoUAT/skyFYX-EXT with a GTX-327? It sounds like a lot of people are happy with the product and its performance once they get the sensitivity setting figured out via the app.

Right now, I have a Sentry Plus for ADS-B In on my iPad with Foreflight. So I guess I can eliminate the Sentry Plus if I install the echoUAT. Or should I keep the Sentry Plus and have both? I think I read somewhere that it might not be a good idea to have both (two sources of ADS-B In)?

I’m just trying to figure out all the ADS-B options and which would be best/easiest/most cost effective, knowing I have a GTX327. The GDL82 is more money, but might be easier to configure? Just a tad confusing at this point so I’d appreciate hearing a little more about your experiences.

Thanks!
 
Back
Top