gres
Full Member level 4
Base amplifier was broken Schmidt. It had not original output transformer thad had been taken from some radiostation, and some new elements that showed someone tried to rebuilt amplifier changing 2x6VPP ending on to 2xEL34PP. Transforer can give only 225CAC and it's too archaic for 2xEL34PP. Luckyly i found good tranformer at internet that perfect suite for amplifier with 2xEL34PP. I also had also ready output amplifier with divided anode winding (2x350VAC without load and 235V with) and two glowing windings ( both with plugs for 4V and 6,3V), i decided to use vacuum rectifier ( firstly AZ4, but finally I used stronger 5C3S, decreasing glowing voltage at resistors from 6,3 to 5V) with series silicon rectifier with choice possibility as in Mes DR. Octal basis for 5C3S i had to placed deeper in chassis because lamp is so big. Choose rectifier is possibility at thanks to switcher at rear panel. Inverter comes from Orange AD15 and is configured for 6N2P or ECC85 ( haven't decided yet). Preamplifier is immortal Soldano Atomic with modifications. Condensers 10nF instead 22nF, second level booster Ck=1uF that is plugged by switcher at potentiometer gain and remove 470 pF. Different is also divider before master potentiometer. Instead 470k/150k is 470k/1M, completely different power filters. At preamplifier are 6N2P-EV instead ECC83.
Still original Schmidt elements are:
- casing ( with new finishing)
- chassis ( renew, with new holes for switchers, potentiometers, and cooling holes)
- ceramic noval basis.
- gain potentiometer 1M/Log integrated witch switcher ( for second level booster)
- speakers slot
- fuse slot
- power button
- 2 lamps EL34 RFT
Specially for this amplifier i've bought 4 potentiometers, 2 PR 10k ( bias system regulation), yellow diode LED, two resistors 1 ohm/5 watts.
More information at https://www.elektroda.pl/rtvforum/topic1448569.html