Not getting any audible ADS-B traffic warnings or terrain stuff. The 750 shows a Bluetooth connection to the 345. Taking it in to the avionics shop on the 29th but maybe just a configuration issue. Any advice?
GTX345, GTN750xi, GMA35 not getting audible warnings
- Thread starter Joe_B1
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Ryan Klems
Line Up and Wait
For terrain alerting, your 750 would need to be 1) On software version >= 6.5 2) Have the audio output on the 750's main connector wired to an unswitch/unmuted input on the audio panel (this is separate from COM and NAV audio) and 3) Have terrain alerting configured in the 750 settings. Do you hear the keyclicks when tapping on the screen of the 750? As to the ADS-B traffic warnings, the GTX345 is pretty restrictive on when it will actually give aural warnings for traffic, so it might be behaving properly, but it is possible that the audio alerting was not connected even though it's a requirement. You could boot the GTX345 to the config mode and go to the audio settings where it has a test function and verify that executing the audio tests that you hear the alerts. Not sure what you mean that the 750 shows a bluetooth connection to the 345... they do not interconnect over bluetooth, what you may be seeing is the GTN can manage the GTX's bluetooth connection, making it a bit easier to handle pairing to the GTX (and if you have the FlightStream 510 that's different but similar).
Ryan Klems
Line Up and Wait
Sorry, I just realized it was a 750Xi, not the pre-Xi, so you definitely have the software to do terrain alerting. But you still need to verify #2 and #3.
Ryan Klems
Line Up and Wait
I can't recall if that tone is generated by the GMA or the GTN, but if you just go to settings -> system -> audio on the GTN750xi and adjust the click volume and see if you can hear it or not. If not, then the main audio wasn't connected to the GMA. You should also be able to verify alerting was enabled by looking at the AFMS your installer would have filled out and provided to you on installation, section 7.5 should have one of the boxes checked as to whether terrain alerting was enabled or not. They should have also provided the GTN Xi instructions for continued airworthiness and a filled out Appendix A indicating if terrain alerting was enabled under the terrain configuration section, and if thorough they would have listed all the audio interfaces to the audio panel in the interfaced equipment list for the GTN in the Appendix A as well.
Der Fliegermeister
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All available alerting can be simulated in remote configuration mode from the GTX. The audio is pinned to an unswitched port at the GMA, not via Bluetooth. Has nothing to do with it.
First thing I would do is verify all the configs. Second thing (and I'm not recommending you do this yourself) is pull the GMA and do a pin inventory. Compare it to the pinout in the IM and determine quickly whether the unswitched audio ports have been used and which ones. If so, then I would start ringing from the GMA to the 750. Sometimes techs can't remember if they used blue for hi or low...ask me how I know lol
First thing I would do is verify all the configs. Second thing (and I'm not recommending you do this yourself) is pull the GMA and do a pin inventory. Compare it to the pinout in the IM and determine quickly whether the unswitched audio ports have been used and which ones. If so, then I would start ringing from the GMA to the 750. Sometimes techs can't remember if they used blue for hi or low...ask me how I know lol
That's honestly above my pay grade. The avionics shop even did something to the GTX and I can't even get into the setup menu. This is after a pretty huge panel upgrade so I guess I can't complain too much. I have an appointment to fly up and have them take a look at it on the 29th so I am sure it will get resolved. Who knows, it may even be something stupid that I did. It's quite a complex system and I am still learning it. Thanks for the reply, I will post back with some answers when they get it all working properly.
WannFly
Final Approach
I have pretty much the exact setup as you, I haven’t heard a traffic callout or terrain callout yet. If you can hear the key tone from the GTN, and on 345 you can test multiple things like set up altitude monitor and go up or down 200 feet you should hear from her, that will prove the config is good.
Next you have to fly really close to something to hear those. I am hoping flying in the ATL airspace will trigger the bitching Betty
Next you have to fly really close to something to hear those. I am hoping flying in the ATL airspace will trigger the bitching Betty
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The thing that got me wondering we were flying from KCON to KASH a while ago talking to approach. They were calling traffic lower than us on a parallel course. He was at about 1000 feet, we were at 2200 descending to 1500. According to ADS-B, we were converging and I opted to make a right 90 to give separation. At one point we were uncomfortably close an not a word from the Garmin. Maybe my filters are set too tight but I will find out next Tuesday at the avionics shop.
WannFly
Final Approach
i dont think you have much control over the filters other than - dont know traffic which are above XX feet. ATC will call those long before Garmin will, especially the panel mounted ones. If you had your EFB connected to the panel via BT, you would hear a whole lot more chatter. The manual has some info on what logic it uses to call out traffic. b/w - did GTN ever pop up a traffic warning on the screen? so has i have seen 2 pop up warning that too while landing, no audio (as it should under 500 AGL or some numbers like that).
This is a topic of discussion between me and Brad @Sinistar quite often, he has GTX 345 but no Nav, he gets lot more calls and rightfully so. I am no authority on garmin products, but my suspicion is when you add the Nav with terrain and all that jazz, it adds various layers of calculation before calling out traffic or terrain. others have reported that when this set up calls for traffic, you better do something about it.
Edit: another thing to check - do you get 500 feet callout while landing? if so, you know GTN is talking to you.
Hang 4
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Only if that feature is set to on. I flew with mine for years before I knew I could get it to annunciate 500ft. Key clicks are the easiest way to test if the connectivity is there.
WannFly
Final Approach
Good point. OP, if you are taking the plane back, make sure the 500 feet callout is configured
NightSkyReader
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Joe, I have a 750 doing the same thing. No clicks, call outs, nada. Did your shop ever get to the bottom of it?
Yes, the big problem was having the key click volume too low (it seems to affect the alerts as well). That is pilot configurable via the settings menu. One other issue was the alert volume set too low and that is only accessible through the installer configuration menu.
NightSkyReader
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I found the click volume setting and it was already at around 75. I turned it all the way up and still don’t hear clicks. I did some research and discovered I can hold down the Home button on boot and get to a config mode where some audio settings can be adjusted but it requires some navigating through pages to get to that screen and I’m worried I’ll break something along the way. Sounds like a job for a pro.
WannFly
Final Approach
before changing anything, take pictures so you can go back to what it was.
Yeah, I would not mess with the config menu!
Ryan Klems
Line Up and Wait
If you don't hear the clicks at all, even when turning them up, then likely the GTN audio was not wired in to the audio panel. This is a separate audio connection from the COM or NAV audio and is required to be able to hear the clicks, 500' callouts, etc.
NightSkyReader
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Why would someone not connect the two? I have an older audio panel: Apollo SL15m. Do you know if I have to upgrade?
It's supposed to be connected to a non mutable input on your audio panel.
Ryan Klems
Line Up and Wait
Your audio panel has two unswitched inputs, so should be no problem to wire it in. Even if they are already in use for something else you can just parallel the inputs with summing resistors. As to why it wasn’t wired in the first place, how long ago was it installed? It wasn’t until 6.5 software came out that the audio outputs did anything but key clicks, so I could see someone perhaps just not hooking it up, it’s an optional (but useful) connection.
NightSkyReader
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The only thing I think might be using those unmuted inputs would be the GFC500 for disconnect annunciations, altitude limits, etc. Does that sound right? No pun intended. Trying to learn all this stuff.
Either way definitely a job for an avionics guy. I’ll start beating the bushes.
I really appreciate the info and help!
Oh and I think it was all installed in 2018 by previous owner but don’t hold me to that. I’ll have to look through the logs.
Either way definitely a job for an avionics guy. I’ll start beating the bushes.
I really appreciate the info and help!
Oh and I think it was all installed in 2018 by previous owner but don’t hold me to that. I’ll have to look through the logs.
If you have ADSB- IN, I am pretty sure that the transponder uses one of those inputs for traffic.
NightSkyReader
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I have a GTX345 that is “connext”ed (or whatever Garmin calls it) to the 750. I have not heard a traffic call out or seen an alert reported on the 750 screen. Maybe havent been close enough yet but just the other day a Cherokee passed right to left about 500 feet below and was close enough that the cowling blocked my view. I was watching it on the 750 but no sort of alert was issued. I would think that would be close enough to generate an alert? Maybe not.
So does the transponder report traffic to the audio panel or does it report to the 750 which in turn reports to the audio panel, or is at least supposed to? I’m ignorant to how all that stuff talks to each other.
Ryan, I think you mentioned earlier in this thread testing audio out of the transponder by booting in config mode. How is that done?
So does the transponder report traffic to the audio panel or does it report to the 750 which in turn reports to the audio panel, or is at least supposed to? I’m ignorant to how all that stuff talks to each other.
Ryan, I think you mentioned earlier in this thread testing audio out of the transponder by booting in config mode. How is that done?
Ryan Klems
Line Up and Wait
The transponder will generate the traffic alerts and generate the audio to send to the audio panel. The 750 will also display a visual alert. The actual traffic alerts are pretty rare, I've had only a couple in my plane over the years.
Here is the section from the 345 IM on getting in to config mode and the audio settings page. You'd get the cursor on the "Test Audio" section and then pick one of the test tones and you should hear it in the speaker and headphones.
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NightSkyReader
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Did what you suggested, Ryan. Thanks for that file. The transponder is definitely talking. Actually changed the voice to female- found it more attention-grabbing than the male voice. All the test messages are loud and clear.
The funny part is, before I even fooled with the transponder I played around with the settings of the Aera 510 (didn’t think to mention I had that too) and noticed in the 510 the traffic alert setting was turned off. I clicked it on, not really thinking it would do much because it’s a little handheld sort of portable thing that is mounted into the panel. But shortly after that I got my first ever traffic call out about an airplane that was in the pattern (I was in the hangar).
So I’m guessing the 510 is what made that call out? Maybe the transponder is talking to the 510 through that plug-in panel mount connection? In that case I guess the 510 is using one of those unmuted inputs in the audio panel?
The issue I have with that is I use the 750 for almost everything and hardly ever even look at the 510. I would rather get audible prompts from the bigger unit that is within easier reach and easier to see. Maybe if it works, it works, and I should leave well enough alone and avoid the expense of checking the plane into an avionics shop.
The funny part is, before I even fooled with the transponder I played around with the settings of the Aera 510 (didn’t think to mention I had that too) and noticed in the 510 the traffic alert setting was turned off. I clicked it on, not really thinking it would do much because it’s a little handheld sort of portable thing that is mounted into the panel. But shortly after that I got my first ever traffic call out about an airplane that was in the pattern (I was in the hangar).
So I’m guessing the 510 is what made that call out? Maybe the transponder is talking to the 510 through that plug-in panel mount connection? In that case I guess the 510 is using one of those unmuted inputs in the audio panel?
The issue I have with that is I use the 750 for almost everything and hardly ever even look at the 510. I would rather get audible prompts from the bigger unit that is within easier reach and easier to see. Maybe if it works, it works, and I should leave well enough alone and avoid the expense of checking the plane into an avionics shop.
Ryan Klems
Line Up and Wait
The traffic alerts come from the GTX345, not the 750. Not sure what kind of alert the 510 was giving, is it interfaced to a separate ADS-B in system like a GDL52 or something? When on the ground you should not have been getting a traffic alert, especially not from the GTX, so wondering if the Aera has it's own traffic input? I think the terrain alerting and 500' callouts are nice to have from the 750 and would be worth wiring in (who knows maybe it even is wired in and they left a molex plug behind the panel that would allow swapping between the 510 and GTN or something). You can pull the GTN and look at the connector to see if the pins are there, if you are comfortable sliding the GTN out.