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Bigbottle MM/MC Hybrid Valve Phonostage PCB

Hi Marra, here are the correct voltages:

V1 pin 1 and 6, 82-95V, depends on MM/MC mode, Jfet characteristics and LED forward voltage. More importantly the 33K anode load resistor should have 105-110V at the high voltage end.
This is from the MosFet and derived from a voltage divider from full HV supply.
V1 pin 3 and 8, around 2V (1.8-2.2) again depends on Jfet characteristics and LED forward voltage in MM mode.

V2 pin 1 and 6, around 130V, depends on the ECC83.
V2 pin 3 and 8, around 0.9V

V3 pin 1 and 3, this is full HT, 225-235V perfect.
V3 pins 3 and 8, around 135V, depends on ECC83. Make sure the 1N4001 is in the right way around.
 
Hi Oliver and Craigtone,

Just to confirm about the transformer specification. A secondary of 165 V @ 100 mA and an 18 V @ 2 A secondary with centre tap is the ideal trafo for this build? Or is it better to have a single 9 V @ 2 A secondary with the diode mod as in post #269? I want to place an order for the toroid tomorrow and just want to make sure of what spec to use.

Many thanks for everything so far, Kevin


P.S. Was just checking my valves, and discovered that I have Teonex, CVC & Elites ECC88s and Elites 12AX7s. Also have 2 Elites 6DJ8s.
 
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Hi Oliver and Craigtone,

Just to confirm about the transformer specification. A secondary of 165 V @ 100 mA and an 18 V @ 2 A secondary with centre tap is the ideal trafo for this build? Or is it better to have a single 9 V @ 2 A secondary with the diode mod as in post #269? I want to place an order for the toroid tomorrow and just want to make sure of what spec to use.

Many thanks for everything so far, Kevin


P.S. Was just checking my valves, and discovered that I have Teonex, CVC & Elites ECC88s and Elites 12AX7s. Also have 2 Elites 6DJ8s.
I always get 9.5-0-9.5v @1A