The EF183 is a high gain variable μ RF amplifier pentode. It is a late 1950s design and superseded the EF85. The EF184 was the straight version of the design and replaced the EF80. All four valves have the same pin connections.
The EF183 is a frame-grid variable-mu RF pentode for use as an automatic gain controlled IF amplifier in television receivers. The heater is suitable for series or parallel operation by AC or DC.
The valve performance figures are given at 40 MHz and the normal TV IF frequency was around 33 MHz.
This exhibit is an import and the maker has used a solid sheet screen. Through the hole one can see the strap joining the two halves of the anode, the open pitch helical suppressor grid and the screen grid that passes flat across the cathode.
The supports above the base are copper.
The thin glass tube envelope is 22 mm in diameter and, excluding the B9A base pins, is 54 mm tall.
References: Data-sheet & 1040. Type EF183 was first introduced in 1959. See also1959 adverts.
