Jesse wrote:
No, you can only have one traffic source. So the traffic must be mixed before the display part, what some systems do, like the Garrecht TRX systems. One must indicate the duplicates on aircraft which you receive in multiple ways. And show only the most accurate one.
The GTX 345 will accept input from the Avidyne 600 TAS systems and combine the output for a Garmin display.
Shorrick_Mk2 wrote:
For the same price you’re much better off with a L3 9000 which gives you TAS (way better than Avidyne’s), ADSB and Mode S all in the same box.
No where near the same price, but it is a nice solution if you are willing to pay for it.
Jesse wrote:
In Europe one has to get approval from the telecom agency to have this kind of equipment, as 978 MHz is generally not allowed in Europe. Europe lacks ADS-R and TIS-B, so you won’t have the advantages as you would have in the US.
I understand that 978 MHz is reserved by ICAO for UAT and there are no prohibitions on emitting on that frequency outside of the US, it is just that not many will have a receiver and it won’t satisfy any ADS-B Out requirement. There are aircraft with dual frequency installations for Out and they should have no difficulty flying outside of the US.
The GTX 345 will accept input from the Avidyne 600 TAS systems and combine the output for a Garmin display.
In such a config, where will the voice warnings come from? Does the GTX345 have its own audio output which could be resistor-mixed with the audio output from the TAS box? (or use an intercom which has two spare unswitched inputs)
NCYankee wrote:
I understand that 978 MHz is reserved by ICAO for UAT and there are no prohibitions on emitting on that frequency outside of the US, it is just that not many will have a receiver and it won’t satisfy any ADS-B Out requirement.
Are you sure on that, as Garmin informed me that permission is required. That way one could choose too use UAT here as well as ADS-B alternative, as there aren’t many ADS-B mandates in Europe for low end to middle class GA.
I just looked up the Dutch application for radio license, though 978 MHz is not included on Dutch aircraft radio licenses. It seems that ICAO might allow US stations to do that, but not for other nationalities?
That makes also seem that Garmins information is correct and that a Dutch customer would need permission before installing an GTX-345, as UAT is not included in his radio license.
NCYankee wrote:
ADS-B In will have limited applicability outside of US except for potential air carrier usage.
Surely ADS-B in will have applicability depending on how many people radiate ADS-B signals. If there is an OUT mandate then IN becomes more useful.
Agreed, but the opinion of transponder manufacturers I spoke to at EDNY was that ADS-B OUT will never be mandated for VFR OCAS in Europe.
Same as the transponder itself isn’t, in most places.
That will keep ADS-B near-useless for traffic avoidance purposes in the areas where you need traffic info most of all.
I am sure this discussion will be different in 20 years’ time, but we are where we are.
Good evening everyone, I emailed Peter a bit over the past few months who graciously helped me with some avionics questions in a Commander that has some boxes in common with his airplane, and we were talking about this very transponder just today. He suggested I post here. I am not in Europe, I live in Texas.
I have Aspen panels, a CX80 GPS, and as of last week a GTX345.
Funny thing about the 345, there is something wrong with the heading input apparently. Since it has both ADS-B reception and a standby AHRS that it projects over bluetooth to an iPad, it has heading input pins. I noticed when leaving my radio shop after the installation, departing on runway 35 and turning to the east, that my shiny new transponder had for some reason rebooted itself in flight during my climb and initial turn. Seemed odd but afterward it worked okay for the remainder of the flight home.
When I got to my home airport I just happened to taxi and park on a heading of 360, which put the 345 into an infinite reboot loop. Apparently someone else, also in the United States, got a 345 and plugged it into the heading pins from his Aspen panel and got the same results. They seem to think the problem lies in the fact that Aspen outputs heading encoding representing values from 0 to 359, instead of 1 to 360. That could explain our issue with a divide-by-zero crash in Garmin’s software, if that’s the issue. Or it could be Garmin’s fault and they’re just blaming Aspen for it, who knows.
I’m honestly not sure if the input of the 345 is ARINC429 or just RS232. If it’s 429, I will greatly enjoy complaining to everyone who will listen (no one) about how wronged I have been by being sold avionics that do not meet spec. How dare the FAA certify devices that are not compliant with the specifications that have existed since 1973! If it’s RS232, no one cares about that even less than no one cares about the 429 incompatibility.
The thread in which we’re all picking on the Garmin rep on the Beechcraft avionics forum is here…
During a boring train ride I happened to look at the Beechtalk thread. I am not sure that the way it is being represented here is entirely accurate. The Garmin rep seems like he is trying to help. It is not clear if the Aspen was approved ie tested beforehand. Of course Garmin should have better filtering but it is a brand new product. These things happen more and more as avionics are more software and less hardware. Suggest we get used to it.
