Sensibly equivalent¶ to:
The UU6 full wave rectifier was produced from 1938 by Mazda and this exhibit shows the typical Mazda envelope and metalising.
Essentially the UU6 is a UU4 on an MO base. See UU6 for internal structure. 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! 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.
The reverse is just metallic paint.
The maximum reservoir capacitor has to be 16 µF.
The classic envelope is 32 mm in diameter and, excluding the MO base pins, is 78 mm tall.
References: Datasheet, 1040 & 1043. Type UU6 was first introduced in 1938.
Absolute Maximum Operating Conditions¶
Updated September 14, 2013.