The CV4005 is a special quality version of the commercial U78 miniature HT full wave rectifier. The construction is of two anodes set around a common cathode assembly. Comparing the images of the U78 and the CV4005 it can be seen that the the SQ version has double micas top and bottom. Research into modes of failure of valves subject to vibration, as found in aircraft etc., found that adding a second sheet greatly reduced the destruction of the mica.
The two anodes are placed at right angles to one another.
The two anodes are placed at right angles to one another.
The thin glass tube envelope is 18 mm in diameter and, excluding the B7G base pins, is 59 mm tall.
References: Data-sheet & 1040. Type CV4005 was first introduced in 1959. See also1959 adverts.