The mercury vapour madness continues. Here is a power supply for RCA 1443 midrange drivers. It uses 816 mercury vapour rectifiers in a bridge rectification arrangement with two 6CG3 TV Dampers.
The RCA1443 has a high voltage field coil which requires 115 VDC at 170mA current. This spec makes a tube rectified supply feasible. Especially when the drivers for left and right are fed in series, then the voltage doubles to 230V.
Smoothing of the voltage is done in a purely passive fashion using chokes and oil caps.
Digital displays have been added to monitor voltage and current.
Output voltage can be adjusted in several steps to account for variations in line voltage and actual current draw from the drivers.
With a current of 170mA the blue glow of the 816 tubes is clearly visible at daylight:
And becomes more visible in the evening ...
... or at night
The 6CG3 tubes provide a nice slow warm up as can be seen in this video clip:
Here seen from another angle: