[time-nuts] Trimble 65256 OCXO

[Dave Brown]

This 10 MHz unit has a 5th pin that I can't find any documentation about. 
There have been posts in the past that have also indicated its use is 
unknown.  Looking at the base, the four connections in the corners are known 
quantities. (ground, EFC, 10 MHz out and + supply) No. 5 is midway along one 
side.
 I thought it may be a reference supply for the EFC pin- with a 12.03 volt 
supply the unknown pin measures at 2.803 volts-which is usefully above the 
required EFC voltage ( ~2.4 volts) to bring it on frequency.
 But does anyone have some hard data on this 'unknown' pin?
 DaveB, NZ