The RCA 4536 is a 4.5 inch image orthicon professional broadcast television pick-up tube. The 4.5 inch tube has a target area three times that of the 3 inch version. This extra area enables an improvement of signal to noise ratio. The 4536 was used in a range of four tube colour cameras in the early 1960s. The first was the RCA TK-42, the four tubes allowed designs with better registration. However, as all transistor cameras became commonplace with less heat generated than the older valve types, the newer plumbican tube cameras reverted to the three tube designs.
The TK-42 used the 4.5 inch image orthicon to provide high resolution luminance information. This was the black and white image. The lower resolution colour information was supplied by three videcon tubes. Initially transmission filters were employed but later developments used dichroic filters with a lower light loss.
The image orthicon has three main sections, image, scanning and electron multiplier. In this exhibit the scanning section is hidden by the silvered part of the envelope and the multiplier is concealed within the lower black part. SeeP807 for a picture of a multiplier section.
The the image section. The springs on the outside are for vibration dampening.
Another view of the image section.
Another view of the image section.
The optically flat input window.
The rectangular target within the image section. The target is scanned by the low velocity electron beam and the return beam carries the weak image signal. The signal is then boosted by the electron multiplier.
The 14 pin diheptal base.
The camera tube in the protective case. The case is 183 mm square and 545 mm tall.
Another view of the case.
The wide glass tube envelope is 79 mm in diameter, and excluding the B14A base pins is 475 mm tall.
Reference: Data-sheet. Type 4536 was first introduced in 1962. See also1962 adverts.
