664493
#664493 3 pins
P1800, 1800S, 1800E
ch 1 - 32.799
until 1970-07
675887
#675887 2 pins
1800E
ch 32.800 - 37.549
MJ 1971 only
1970-08 - 1971-07
685946
#685946 2 pins, later without

1800E
ch 37.550 - 39.414
1971-08 - 1972-07-22

1800ES
ch 1 - 8.077
1971-08 - 1973-07-27