The MVS-Pen is a variable μ RF pentode designed for radio receivers. It is indirectly heated and features the then standard UK heater of 4.0 V at 1.0 A.
Initially in 1933 the MVS-Pen came with a B5 base cap. In the same year the B7 base version was released.
Thereverse is plain zinc paint.
The classic envelope is 45 mm in diameter, and excluding the B7 base pins is 105 mm tall.
References: Datasheet, 1040 & 1043. Type MVSPen was first introduced in 1933.
Absolute Maximum Operating Conditions¶
Thanks to Andy Cowley for supplying the above PDF datasheet.
Updated March 17, 2014.