Wiring Harness, For connecting a Trig TT23 Transponder Unit to an Air Avionics ACD-57 Air Control Display Unit
This is a pre-wired wiring harness which makes installation faster and trouble-free.  It may also save you delays and repair bills should you accidentally connect something incorrectly.  This wiring harness is assembled and tested using a cable tester by Larry Goddard.  It has a DB-9f connector at the ACD-57 end and a DB-25m connector at the TT22 or TT23 end.  It also includes power input leads for 10 to 30 VDC. The power input leads exit the DB-25m connector at the TT22 or TT23 transponder end.  The power input leads are 0.5 m long.  The 0.5 m length is perfect for installations where the TT22 or TT23 Transponder Unit will be mounted near the ACD-57 display (such as in front of the instrument panel in the nose of a glider).  For installations with the TT22 or TT23 Transponder Unit mounted behind the pilot I recommend the 3 m version of this cable. 
Note: Wiring for external "Squat" and "Ident" switches is included.  The squat switch input is for aircraft with built-in squat switch.  Such as the Peregrine-Airspeed-Switch-Kit. The use of a squat switch is highly recommended for sailplanes that will fly in wave - so the transponder will remain in flight mode when the GPS position remains stationary.