Hi,
I'm looking for the sce manual/schematic of this little Proton integrated amplifier with Sanken transistor from the late 80s...
Anyone please ? One channel is buzing/huming and pass no sound from the source... Lock down debugging project... would like to check the power trafo voltages.
Many thanks
I'm looking for the sce manual/schematic of this little Proton integrated amplifier with Sanken transistor from the late 80s...
Anyone please ? One channel is buzing/huming and pass no sound from the source... Lock down debugging project... would like to check the power trafo voltages.
Many thanks
Hi,
So I found something near, the shematic of the Proton M520... The am-200 has just different sankens and a little more volts in the regs, biass would not be the same as well, but the circuit board is very similar.... no speakers protection but a delay circuitry, symetric design for both, all discrete... the sankens are used in some Accuphase... the Proton has old carbon pots and no metal films resistors but the biggest wattages. one Sanken SC2887 & A1186 per channel...
one pot resistor for the ot voltage biass and that's all !
I recaped the culpritt channel : it plays louder than the other channel and in the same time plays at zero volume pot while still increasing the spl when turning up the pot ?
Does such description talk to anyone please ? What should I check then ?
Buffer after the pot or a bc transistor before the big sankens ?
So I found something near, the shematic of the Proton M520... The am-200 has just different sankens and a little more volts in the regs, biass would not be the same as well, but the circuit board is very similar.... no speakers protection but a delay circuitry, symetric design for both, all discrete... the sankens are used in some Accuphase... the Proton has old carbon pots and no metal films resistors but the biggest wattages. one Sanken SC2887 & A1186 per channel...
one pot resistor for the ot voltage biass and that's all !
I recaped the culpritt channel : it plays louder than the other channel and in the same time plays at zero volume pot while still increasing the spl when turning up the pot ?
Does such description talk to anyone please ? What should I check then ?
Buffer after the pot or a bc transistor before the big sankens ?