The CV545 is an indirectly heated HF pentode that employs the old UK standard heater rating of 4 Volts at 1 Amp. As no CV545 data could be found the commercial PDF is given below.
Mazda give the use of the AC/SP3 as for Short Wave receivers and Television Sets and as a video amplifier it can modulate a cathode-ray tube. The AC/SP3 features a special heater construction to reduce induced mains hum and making it suitable for the early stages of amplifiers.
The commercial valve was graded on test into premium low hum A valves and the rest as grade B - fine for normal use. This probably explains the written A on the base cap
The reverse is plain zinc loaded screening paint.
This top view shoes the tops of the grid supports as well as the cooling loop on the control grid support.
The classic envelope is 39 mm in diameter, and excluding the B7base pins is 111 mm tall.
