Sensibly equivalent¶ to:
The RL18 is older Type designation for the EC53 miniature UHF oscillator triode. This class of valve dates from the late 1930s and was intended for VHF receiving applications (TV front ends and Radar IF Strips) and as active probes for VHF valve voltmeters and oscilloscopes. The size of the valve relates to the need to make its input and output leads thick and very short compared to the wavelengths at which it is required to operate.
The internal design is similar to the acorn valves.
The thin glass tube envelope is 15 mm in diameter and, excluding the base pins, is 50 mm tip to tip.
References: Data-sheet & 1043. Type RL18 was first introduced in 1946. See also 1946 adverts.
Absolute Maximum Operating Conditions¶
Updated April 09, 2015.