[May 17, 2016]

Tonight was dedicated to getting all of the wiring in place for the GTN650. The following needed to be done:

  • Add in extra power and ground wires

  • Replace the BNC connector on the GPS Antenna coaxiax wire with a TNC connector

  • Remove old large-style female pins from the COM wires (PTT, MIC, 500 Ohm COM) and replace with miniature make connectors.

The first step was to solder on new ground and power wires to existing feeds.

Next I chopped off the old BNC connector.

I tested out how much wire I needed strip off of the GPS coaxial cable for the TNC male connector.

It wasn't the most fun project to strip and crimp in this limited space, but the BNC connector has been replaced with a TNC connector.

I started assembling the connector clam-shells. The P1001 connector gets a configuration module which conveniently fits in the connector housing.

All of the pins are installed and double checked.

Hmm, what next? I was thinking about putting the panel back in, but what if I forgot a wire? Or what if there was something not pinned out correctly? I needed a way to test it out without the panel installed. I used my laminated "HBP" Oshkosh sign to act as an insulator so the connectors on the switches wouldn't accidentally get grounded out. I also set my EFIS on a piece of wood on top of my panel supports so I could make sure it was sending and receiving RS232 and ARINC data.

I plugged the 650 into the backpanel without using the tray. Things seemed to be working! The unit powered on and I was able to update the databases.

More good news! ARINC data was being sent to the GRT EFIS after I configured the GTN650.

GPS is locked on!

Hmmm, the NAV doesn't appear to be working. PTT/Transmit on the COM radio wasn't working either, however, I could hear the AWOS broadcast.

These top two messages don't seem all that positive. It's about 11:30pm now, and I am too tired to continue to debug this issue. I will research it tomorrow and see if I can't find that root cause of the issue. I am sort of baffled, because the wiring has been triple checked. I hope it's not a bad unit.



Last Modified: May 19, 2024