Open or shorted wire in your encoder harness? A bad input gate on the transponder?
The EET-200 provides the avionics technician a clean, quick and reasonably priced method of emulating an altitude encoder output by providing a known good altitude code source to aide in isolating each data bit D2 through C4. Simply unplug the altitude encoder and substitute the EET-200; rotating the knob will move the transponder through a variety of preprogrammed altitudes testing each data bit in sequence.
Suspect a problem with the altitude encoder?
Unplug the encoder and plug both the transponder and the encoder into the EET-200. Use the built in vacuum syringe to simulate any altitude from below sea level to over 30,000 feet (using supplied 12\x94 x 1/8\x94 tubing, not pictured). Compare the encoder output to the supplied altitude code chart to determine if an error is present.
Strobe function not working?
Simply toggle the strobe switch on the EET-200 to simulate an open strobe on the digitizer or the transponder.
Power supply connected correctly?
Simply unplug the altitude encoder and substitute the EET-200. If the power LED glows green then your good to go, if it glows red then your power is connected improperly.