GTS800 Active Traffic System

Since I plan to fly outside the US and in areas where TIS-B is not available, I got a GTS800 active traffic system for "cheap" on eBay (as in, 75% less than a new one). It was advertised as new but missing papers (A&Ps, please keep losing those papers!), so I wanted to verify that it was working and that it was indeed new.

The unit has two 78-pin high-density connectors and one 37-pin connector (plus the 8 connections for bottom/top antennas):
GTS800 connectors
Checking the pinout in the installation manual, it seemed I only needed to connect a few pins in the 37-pin conector for power, plus a few pins in one of the 78-pin connectors for USB to the computer. I got breakout boards for that (this, this and this):
Power and "remote power on" connections on 37-pin breakout board
USB breakout connected to the 78-pin breakout board
then connected it all:
Break-out boards plugged to GTS for testing
I had to get a special A-to-A USB cable, after a "duh" moment when I realized the USB breakout card I got had the same connector as the computer - I should instead have gotten this one. Luckily I had that cable.

My first attempt was frustrated - it just didn't turn on or get recognized by the computer, and the power supply was making a weird noise - turns out I was trying to use a 2A power supply, and it requires more than that (manual says 2.6A, I saw 2.1A after it starts up). Tried a different power supply, and it just worked!
GTS plugged to a proper power supply (the bottom one had a 2A current limitation)
The software showed me exactly what I wanted to see - that it had been turned on for only about 5 minutes, and it had recent firmware versions (so it was indeed new):
The software detects it!
Recent firmware versions
At first I was also worried that the fans didn't turn on, but as soon as the temperature reached about 35˚C, they turned on and the temperature stabilized.

With this, the GTS can go back to the shelf and wait until it's time to actually install it - at that point, I'll need to figure out its ground plane - probably following the recommendations from this VAF post as well as this blog post - not trivial, but doable.

Special thanks to VAF user Strasnuts for the help!

Tailcone bottom done!

Progress has been slow due to a number of other events (such as studying for my CPL-AMEL checkride), but we finally finished riveting the bottom part of the tailcone! Next step is to attach the aft deck:
No clecos on the bottom part anymore! :)
The only exception is the avionics shelves in the front - I left those holes open to make it easier to crawl inside the cone. I'll rivet them after the top skin is on.

As I prepared to rivet the longerons below the aft deck, it became apparent that the F-1011 bulkhead was rubbing against it, and that could cause damage and fracture later:
Bulkhead rubbing against longeron
As much as I hate filing and removing primer with that, the solution was to file it down so they don't touch:
Bulkhead filed clear of longeron
Not much more details to share - it was mostly repetitive riveting work.

Time lapse:

Total tailcone time: 192.9h
Total tailcone rivets: 1438

More tailcone riveting

1161 rivets later, I'm probably about halfway done in riveting the tailcone:
Side skins mostly riveted
I had a lot of help here, so I could back-rivet most of it, with my wife holding the bucking bar:
Wife helping me back-rivet
Next up is riveting the two rows that join the bottom and side skins (clecoed above), then the aft bottom skin.

Time lapse:

Total tailcone time: 180.2h
Total tailcone rivets: 1161