The KTW63 is a beam or kink-less tetrode for HF and IF amplification in broadcast receivers and replaced the W63. The valve is variable mu designed to have the stage gain controlled by a voltage derived from the final rectified signal.
Note: The 6K7 family has pin 5 connected to the suppressor grid whereas the KTW63 has an internal connection to g3 and pin 5 has no connection. These valves are sensibly equivalent but not identical.
This exhibit has the etched ellipse containing the Type designation and is this a UK M-OV product.
The branding is given by the paper label. Marconiphone being a consumer brand.
The top of the screen and within is the top mica showing the tops of the electrodes.
The classic envelope is 39 mm in diameter and, excluding the IO base pins the valve is 103 mm tall.
References: Data-sheet & 1040. Type KTW63 was first introduced in 1938. See also1938 adverts.
