I'm trying to find the pinout for an obsolete SEI crystal oven, which
contains a HC6U sized crystal socket. SEI are now part of C-MAC, who were
unable to provide me with any information.

The oven measures 26 x 23 x 49mm including 4 pins. Presumably 2 pins are for
the crystal and the other 2 for the oven heater - but can anyone advise on
the necessary supply voltage?

The label reads:

SEI
CRYSTAL OVEN
QC. 1500 A
TEMP. 75 C
SER. No. 077094
MADE IN ENGLAND

Tnx
Hans G0UPL
http://www.HansSummers.com