Sensibly equivalent¶ to:
The 1U5 is a diode pentode designed for detection and first audio voltage amplification in light weight portable radio equipment and the sensitivity of the pentode allows for a low anode voltage thus saving weight on the HT battery.
The diode is a small bright box near the top of the envelope.
Looking over the rim of the bright anode reveals the three wire grids. The open pitch suppressor grid close to the anode, the tighter pitch of the screen grid and finally the control grid close to the filament.
The thin glass tube envelope is 18 mm in diameter, and excluding the B7G base pins is 47 mm tall.
References: Data-sheet & 1040. Type 1U5 was first introduced in 1945. See also 1945 adverts.
Absolute Maximum Operating Conditions¶
Updated January 05, 2022.