16-05-2018, 11:21 AM
(16-05-2018, 09:18 AM)Geordie McBoyne Wrote: Curiously, the AW36-21 CRT is date stamped R7J, late 1957 or is it 1967?
R = Mitcham
7 = 1957*
J = October
* Two reasons: no domestic valve so, presumably, no CRT production at Mitcham by 1967 and, to differentiate between the 50s and 60s, a week number from 1 to 5 was added, thus B7J2 would be Blackburn, 1967, October, second week of month but B7J would be 1957.
