65MooneyPilot Posted March 8, 2023 Report Posted March 8, 2023 I have a GDL 88 hooked up to my Garmin 175 for ADSB in. I bought it used and installed it. For some reason I am not receiving ground targets. In the 175 it says ground targets not available. How do I enable the ground targets? Quote
65MooneyPilot Posted March 10, 2023 Author Report Posted March 10, 2023 Well not to many people have this combination I am guessing. I will probably go to a Garmin shop one of these days and have them look into it. It maybe just a setup issue. In the air it works great which is where it counts. Quote
JohnnyM Posted March 12, 2023 Report Posted March 12, 2023 (edited) As pointed out, this statement was incorrect. I removed to stop presenting incorrect info. Edited April 14, 2023 by JohnnyM I was wrong. Quote
gmonnig Posted March 12, 2023 Report Posted March 12, 2023 33 minutes ago, JohnnyM said: The GDL 88 is an ADSB out source. To get ADSB in, you would need something to receive it. Portable GDL 39, GDL52 would receive and provide the traffic/weather via Bluetooth to the GPS 175 Sent from my Pixel 6a using Tapatalk This is wrong. The GDL82 was ADSB out only. The GDL88 is ADSB IN/OUT. I have the 88 and it does bring ADSB in and displays it on your GPS, in my case a GTN650. As for the OP, I am not sure what you mean by ground targets. AFAIK, you need to be receiving ADSB towers to display targets and I don't receive any towers until a couple hundred feet off the ground. 1 Quote
ArtVandelay Posted March 12, 2023 Report Posted March 12, 2023 This is wrong. The GDL82 was ADSB out only. The GDL88 is ADSB IN/OUT. I have the 88 and it does bring ADSB in and displays it on your GPS, in my case a GTN650. As for the OP, I am not sure what you mean by ground targets. AFAIK, you need to be receiving ADSB towers to display targets and I don't receive any towers until a couple hundred feet off the ground. Not quite, you don’t need towers IF other planes have 978 ADSB transponders, the towers just rebroadcast standard 1090 signals on 978 band. OP should boot up GTN in configuration mode, and check settings for ADSB/88. Quote
glbtrottr Posted March 12, 2023 Report Posted March 12, 2023 This is wrong. The GDL82 was ADSB out only. The GDL88 is ADSB IN/OUT. I have the 88 and it does bring ADSB in and displays it on your GPS, in my case a GTN650. As for the OP, I am not sure what you mean by ground targets. AFAIK, you need to be receiving ADSB towers to display targets and I don't receive any towers until a couple hundred feet off the ground. You’re right, and not just.The GDL 82 was a neat little device due to ease of install - except for needing to add the waas GPS antenna for it. What is cool is that you literally daisy chain your existing transponder cable to the unit, with another cable coming out of it to the antenna. Power and ground, voila! ADSB out with out fear of a stolen Tailbeacon as people experience. I’ve installed a bunch. Avionics shops love these because they can make bank installing them at their current rates and billing practices.The GDL88, and the 84, which is a crippled 88, both provide in and out as you correctly stated. Install is a bit more involved. The 84 is a gdl 88 which has a built in SBAS / gps location receiver, but no provisions for panel mounted “in”. Just portables when paired with a flight stream 110/210.The Garmin documentation shows that you can send in your 84 to be upgraded to an 88, but last I checked with them they were not offering it. Bear in mind an 88 ceiling is 18k unless paired with a GTX330es/gtx33. An extra 4 lbs to get rid of a panel mounted transponder plus the added cabling… 2 Quote
skykrawler Posted March 12, 2023 Report Posted March 12, 2023 On 3/7/2023 at 11:54 PM, 65MooneyPilot said: I have a GDL 88 hooked up to my Garmin 175 for ADSB in. I bought it used and installed it. For some reason I am not receiving ground targets. In the 175 it says ground targets not available. How do I enable the ground targets? Are you receiving traffic at all on the 175? If not, the data line providing the input to the 175 may not be connected. The wording of your post implies it wasn't installed by a 'qualified' installer. Quote
gmonnig Posted March 12, 2023 Report Posted March 12, 2023 1 hour ago, glbtrottr said: You’re right, and not just. The GDL 82 was a neat little device due to ease of install - except for needing to add the waas GPS antenna for it. What is cool is that you literally daisy chain your existing transponder cable to the unit, with another cable coming out of it to the antenna. Power and ground, voila! ADSB out with out fear of a stolen Tailbeacon as people experience. I’ve installed a bunch. Avionics shops love these because they can make bank installing them at their current rates and billing practices. The GDL88, and the 84, which is a crippled 88, both provide in and out as you correctly stated. Install is a bit more involved. The 84 is a gdl 88 which has a built in SBAS / gps location receiver, but no provisions for panel mounted “in”. Just portables when paired with a flight stream 110/210. The Garmin documentation shows that you can send in your 84 to be upgraded to an 88, but last I checked with them they were not offering it. Bear in mind an 88 ceiling is 18k unless paired with a GTX330es/gtx33. An extra 4 lbs to get rid of a panel mounted transponder plus the added cabling… Yep, these were/are good units. When I did my avionics upgrade I did add a used remote GTX33ES to remove the panel mounted GTX327. These perfectly good GTX33ES go for about $1k-$1.5k. Every Cirrus and TBM with the Garmin suite had them, there are a ton of them out there. That made the plane useable worldwide with 1090out instead of 978. Quote
65MooneyPilot Posted March 12, 2023 Author Report Posted March 12, 2023 Yes , in the air I am receiving all the blue targets. 1090ES does not need to be rebroadcast, it should be on my IPad as brown targets if they are on the ground. I am going to recheck the setup and see if it looks correct. The 175 says the ground targets are not available. Yes I am not a Garmin dealer but I am an A&P that knows how to read wiring diagrams and the harnesses are built by Approach Systems. I know plenty of installers that tell me the Garmin setups can be a challenge. My GDL 88 is a receive only unit. Later models have ADSB out which I don’t need because I have a Trig mode S Transponder with ADSB out. Quote
carusoam Posted March 12, 2023 Report Posted March 12, 2023 How are we defining ground targets? As today, with modern ADSB out… we don’t wait to set our transponders to ALT at the runway prior to T/O… At large airports with ground equipment with transponders… this may be the ground targets being referred to? ADSB in, with re-broadcast and local ADSB towers… some people get lots of data while still on the ground…. Depending on their location. Could be the way we are defining what we are looking for… Great details GT, thanks for sharing them! Best regards, -a- Quote
65MooneyPilot Posted March 13, 2023 Author Report Posted March 13, 2023 Ok, here are the targets I am talking about. When you are on the ground and taxiing on the airport you should see other taxiing aircraft. They are brown in color. If you have your taxi chart selected you will see them moving on the chart. I wanted to find out if others with GDL88’s receive the ground traffic. Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.