The underside of the SA.97. The top half is clearly the PSU. There are two transformers
and one choke. The metal rectifier serves to provide a negative voltage to complement
the output of the 5V4G. This is necessary for symmetrical drive to each pair of deflector
plates. Although not clear from the photograph, there are two EHT rectifiers (long
thin Tufnol tubes). These provide -
Across the bottom, left to right is the Timebase generator, +250V stabiliser circuit and +210V Stabiliser circuit.
The frequency marker pulses are ‘merged’ with the fly-