Garmin CNX80 - Any other users?

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Just installed a Garmin CNX80 with a S-Tec (GPSS)in my Cessna 182P
based on Vancouver Island, B.C.
The CNX80 takes quite a while to get use to (I had a Apollo 2001NMS
before)but I'm getting there! Wondering if anyone else has this
combination , and if so, I would sure like to compare notes with

-- Ken Stevenson, March 13, 2004


So how do you like the CNX80 and is your 2001NMS for sale? If so what components are included. Charlie McDougal

-- Charles McDougal, April 3, 2004

I was one of the first customers to buy the CNX80 back in June 2003. It took me a while to figure it out. I watched the video,read the book and so on. Not much help. I had to simply press buttons and figure it out the hard way. It had some bugs at first. I worked with Mike in Tech(at Garmin). The voice annunciator would say "500ft" at the incorrect altitude when on a GPS or ILS approach. It kept saying "Localizer Alive" when there was no Loc feq or approach programed in.It was interesting listening to ATC while another voice was in your headset at the same time. Then they updated the software and it did solve those,but there were a few other ones as well. When pressing Direct to a VOR it gave you a "curved course" if you will.They told me that that issue would not change. I just sold my 182 with the CNX80 in it. That was a bummer. I just purchased a U206 and need all new avionics. I did get very proficient with the CNX80 and really love it now. It does things that the Garmin 530 does not. I haven't made my decision as to which GPS to install but I am still leaning toward the CNX80 over the Garmin 530.

-- jeff Simunaci, April 9, 2004

I am now having a CNX80 installed in my V35B, along with an HSI and SL15 audio panel. An ADF and M1 Loran are being removed. To improve balance, I asked for the remote gyro to be mounted behind the instrument panel instead of in the tail. Has anyone else heard of doing that in a Bonanza?

First Impressions: I have never become competent at using an IFR GPS, but this unit (only used the simulator so far) seems pretty easy to use. Perhaps never learning a different model is an advantage. The user manual is really poor. Though not important, the installer told me that the CNX80 does not talk to my old DME because the CNX80 does not support parallel digital graycode. Garmin sells a box that fixes that. I am concerned about when I will receive the new 2.0 software that will presumably allow gamma-3 approaches.

I will post again when I have some experience. PP

-- Peter Peterson, April 16, 2004

Hi Peter. Since I don't have a Bonanza I cannot answer that question.But I do know about the encoder/gray box issue with the CNX80. I had to replace my encoder as well.The simulator/training deal is alright although you will find you will have to make certain key strokes or your flight plan,approach,or direct to will not function. I too had not used any other IFR cert GPS until the CNX80 and only know it. That could be a good thing for you too. Good luck,Jeff

-- jeff Simunaci, April 16, 2004

My faux pas - I mentioned the non-compatibility w/ the DME - which is true, but in my haste I incorrectly mentioned "parallel digital greycode". The DME has a parallel input while the CNX80 only supports serial-interface DMEs. Jeff - I also had to buy an altitude encoder because the CNX80 would not talk to my old one. It seems the CNX80 is conspicuous in this shortcoming. PP

-- Peter Peterson, April 19, 2004

Does the CNX-80 have an ILS display or must it interface with a CDI? Has anyone installed it in an experimental and if so was the installation instructions adequate? I have a MustangII with GX50 and am somewhat interested in replacing my GPS and #1 NAV/COM.

-- Wayne Sweet, June 24, 2004

Hi Wayne - I believe the long awaited 2.0 software (Q3???) is supposed to have an HSI or similar display screen. I don't know if it would be legal to use that to shoot an approach with.

I am still fighting some technical problems with the installation and the unit.


-- Peter Peterson, June 26, 2004

Right now you need a CDI with the cnx80. I believe that the 2.0 software is available now and there is a recall to fix a display problem and they will install the 2.0 when they fix the display.

I just did a gps aproach yesterday and when I broke out at 1500ft I found I was off the centerline of the runway by 400ft or more with the cdi centered. Has anyone else had this problem?

-- Walter Zaverucha, August 31, 2004

My GX50 can be manually set to 1 mn CDI sensitivity from the default 5 mn, which is required for the Navaid Device to accurately track the GPS. Can the CNX80 be so configured?? I have read the Pilot's Guide and the Installation Manual, with no indication of how to do this.

-- Wayne Sweet, October 3, 2004

Select the "Latest Website Updates" option. The 10/05/2004 entry has a list of the 2.0 software features.

I will be sending my unit in when I am ready to have the aircraft down for a bit.


-- Peter Peterson, October 7, 2004

I've had a CNX80 in my Saratoga for a year, and I love it. IFR from KSLK ATC often throws a full route clearance with airways. The CNX80 has the airways, and it is EASY to plug in the new clearance and still fly the airplane. With the Garmin 400/500 you have to get out your map and look up all the airway fixes & enter them.

It has been accurate on all GPS & ILS approaches, and altitude warnings are good too -- if you enter the baro correction, or have baro input.

-- Sandy Trevor, October 8, 2004

We installed a CNX80 with moving map MX20 last year in our 182P. The CNX80 takes a while to get used to, and is best learned using the downloadable simulator program on the ground, then trying it out in the air. Once learned, though, the combination is terrific. Interfaces great with my HSI and autopilot...almost too easy to fly x-country..approaches are easily selected on the fly, and it continues through the missed to the hold, which are also simple to do on the fly. I probably had 50-70 hours between on the ground and in flight before I figured out all the features, many subtle ones, and Im very satisfied with the combo. Only problem? Transponder, navcoms, GPS all are in the CNX80, and the MX20 depends on it too. There is a tendency to become completely dependent on the CNX80, and a good Plan B is imperative if the CNX goes south (never has).

-- Richard Freed, October 10, 2004