Sensibly equivalent¶ to:
The DF33 is a variable μ RF pentode for dry battery operation. Mullard designate this device for service at both RF and IF in broadcast receivers.
The filaments had to have the lowest possible consumption due to the cost of the dry batteries.
On the reverse can be seen the wire connection to the metal loaded paint. The adhesive circle holds the wire in place to ensure good contact with the paint.
The wide glass tube envelope is 29 mm in diameter and, excluding the IO base pins, is 68 mm tall.
References: Data-sheet, 3002 & 1040. Type DF33 was first introduced in 1939. See also 1939 adverts.
Absolute Maximum Operating Conditions¶
Updated January 05, 2022.