July 29th, 2001
Today I spent some needed time finishing the throttle quadrant rebuild. I needed to rewire the switch assemblies on both grips to allow easier interfacing to the EPIC input matrix.
This is what the inside of the left throttle grip looks like. To prevent corrosion of the switch wiring everything has been potted with a gray RTV silicone caulking. The white area is new RTV that was used when one of the switches was replaced at the depot. Unlike what I did for the right grip, I left all the original wiring in place. This was done to avoid all the hassles of digging out the RTV and burning through the protective coating that the solder terminals had applied to them. During the rewiring work on the right grip, I destroyed the RETICLE STIFFEN/SRM REJECT switch in my attempts to remove it. Fortunately, I had a nearly exact replacement for it in my bench stock. I got lucky once. Lesson learned. Here is what the "working" face of the left throttle grip looks like
From right to left, the switches are: WEAPON SELECT, EWWS INTERROGATE, SPEED BRAKE, UHF1/UHF2 TRANSMIT, IFF INTERROGATE/AIM9 BORESIGHT, and TARGET DESIGNATION CONTROL. The Target Designation Control that's used in the F-15C is electrically similar to the F-16 flight control system in that they both use measurement of force to translate motion into electronic signals.
This is what the TDC looks like after being removed from the grip. The shaft that sticks out is where the cursor "button" attaches to.
In this image, you see the back of the TDC unit. The round assembly is the force sensor portion of the control. This translates finger pressure into cursor movement on the radar display. To the right, you can just make out the pushbutton that tells the radar system to lock on to the selected target. When you press on the cursor control, the whole assembly slides back to press this button. It's actually a pretty neat design.
This is what the cursor button itself looks like. This was a pain to remove due to the requirement for a 0.028 hex wrench to remove it. Fortunately, Robbi was able to find one at Tacoma Screw Products.
Prior to soldering up the DB15 connector to the wiring harness, I had to disassemble the upper portion of the quadrant so I could route the wiring in the location used by the old wiring harness.
Here is the throttle completely re-assembled with the new wiring harnesses on display. The right grip uses a female DB9 connector and the left uses a DB15. The TDC cursor controller is not connected right now due to the high cost of the signal amplifiers needed to properly use it. Back to the Tech Index