Nice. ;) I currently have an RM547 and a 555. I
lack the power
supply umbilical cable for the 555 though. I had a 545A many years ago.
I think the connectors (althoguh maybe not the back shells) are still
abailable, if expensive. It should be possible to make up the cable.
Oh, and even
the heater supply to most of the valves is regualted, by a
circuit that takes into account the RMS value of the waveform.
Glorious.
Of course :-)
In case you'rte wondering, the circuit is based round a bright-emitter
diode in the PSU box. The filament of this valve runs off the instument
heater transformer. The anode current thus depends on the heater
temperature, and thus the RMS value of the heater voltage. The anode
current controls the grid voltage of a pentode, the anode circuit of that
contains the cotnrol windign of a saturable reactor which controls the
suppl to the hater transformer. A very elegant circuit.
I also have a 1S1 plug-in (1GHZ 'sampler', it aliases high-frequency
repetitive signals down into the passband of the 'scope) and it
associated cathode follower probe (which has a small triode valve inside
the probe itelf). And yes I have used it.
-tony