Sensibly equivalent¶ to:
The UU7 is a full wave rectifier. It probably dates from the late 1930s.
Essentially the UU7 is a UU5 on an MO base. Quite why they decided to metallise these rectifiers remains a mystery but the only obvious consequence was that they tended to overheat until the metallising corrected the problem by flaking off! as can be seen above.
This series of rectifiers was not as robust as the stalwart UU5, at least until the 1950s when Mazda seem to have realised that domestic HT rectifiers do not need metallisation See UU7
The maximum reservoir capacitor is 16 µF.
The classic envelope is 44 mm in diameter and, excluding the MO base pins, is 95 mm tall.
References: Datasheet, 1040 & 1043. Type UU7 was first introduced in 1938.
Absolute Maximum Operating Conditions¶
Updated February 20, 2013. shape:classic construction:pinch type:rectifier.fw age:1930.1940 base:mo heater:4.0v pins:8 pin:1.h.k pin:2.- pin:3.a(2) pin:4.- pin:5.a(1) pin:6.m pin:7.- pin:8.h