Sandia Starts Shipping STX 165 Transponder

New instrument packs many functions in a small package.

Sandia STX 165
Sandia STX 165
Sandia STX 165

Sandia Aerospace, the Albuquerque, New Mexico, avionics manufacturer, said it has started delivering its new STX 165 Mode C transponder with built-in encoder. Designed to occupy a minimum of panel space, the transponder can slide into a one-half 3-ATI opening, and measures seven inches deep.

In case you’re not familiar with the term “one-half 3-ATI,” here’s what it means: A 3-ATI measurement is a standard three-inch airline transport indicator cut out – the typical size of round-dial instruments such as the airspeed indicator, altimeter and so on. One-half 3-ATI means the instrument takes up the form factor of a 3-ATI hole, but at only half the height.

In addition to displaying transponder code, the STX 165 can also read out pressure altitude, includes three timer functions and can be purchased with optional OAT probe, density altitude output and icing alert. List price of the STX 165 is $1,700.

Sandia has also introduced a remote version of the transponder, the STX 165R, designed to interface with onboard nav management systems or for use UAV applications.