The CV5358 (ECC88) is a VHF double triode with separate cathodes. The font that the Type is printed in is typical Mullard.
The ECC88 was designed for service as a cascode amplifier in the front ends of VHF radio receivers. One triode acted as the local oscillator and the other as the mixer (frequency changer).
The re-entrant anode giving a small working area and larger heat sink. Small capacitance construction.
Face view of one triode. The insulated heater is a hairpin of coiled wire. The cathode tube is a flattened oval. The mica sheets are doubled to give resistance to vibration and shock.
A different view: the central screen is clearly seen.
The thin glass tube envelope is 20 mm in diameter and, excluding the B9A base pins, is 47 mm tall.
References: Data-sheet & 1040. Type CV5358 was first introduced in 1958. See also1958 adverts.
