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The power supply has stabilized regulated voltage 115-350V/170mA made on the cheap and readily available 2 x PL504 and EF80 tubes. Polish UL1550 circuit works as a source of reference. It is much more stable than the classical stabilizer diodes, works successfully with currents of 2-6mA. This allowed a significant reduction of losses across the resistor limiting stabilizer current.
A classical circuit bridge rectifier was applied, which in addition to great voltage and less power losses, allowed for increasing the capacity of the filter, ie, series-parallel combination of four capacitors 220uF/250V which allowed to obtain a set of a total capacity of 220uF/500V. Voltage on them is 450V, also discharging resistor 220kohm/2W was applied.
For such a simple design, voltage is remarkably stable. Its ripple at 300V/80mA consumption is about 50mV.
Unusual voltage of PL504 lamps glow, 27V, was received from the wound transformer 2x12V to 2x14V and adding 1,5ohm reductive resistor.
Besides, the power supply has also alternating voltage 320V/170mA, 6,3V/3A, 5V/3A and stabilized 12,6V/1,5A dedicated to preamplifier lamps glow and other sensitive circuits.
The device was built using a circuit stabilizer 7812 with two diodes Si plugged between the system and the mass, resulting in 13,4V voltage. This voltage is fed directly to the transistor base 2N3055, and as a result of the voltage drop at the output by B-E connector (emitter), there is 12,6V unchanged from the charging current.
Link to original thread (useful attachment) – Lampowy stabilizowany regulowany zasilacz 115-350V 170mA
