Phase Splitter Unit

Part No. B4A A81 160 001
Serial No. GAF 019
Mod. No. B7939

This unit was supplied with single phase 115V AC at 400 CPS from the Type FI 45G inverter. The Sperry B22 gyro required three phase which was generated within the phase splitter.
The specification called up the main phase to be 115VAC -+ 5volts .
This could be adjusted by RV1 on the inverter. The other two derived phases to be 115 VAC -+10. As the phase splitter unit is load dependent these voltages may not be achieved for all attitude gyros (to achieve this it may be necessary to change capacitor C1 to either 0.56µF or 0.68µF.)
The unit also contains a transformer that supplies 19 +/- 2 V AC to the erection system within the B22 gyro. As the erection system uses mercury switches, the 19 VAC was switched off by a relay on selection of Climb, throttle open or shut, this was to reduce acceleration and deceleration effects on the mercury switches.

This item's case bears various marks:
"756/lss5";
"Phase Splitter Unit";
"C.T.N.S 264";
"Warning High Voltage 115V"