I have Beomaster 1000 (Type 2301) that after some months of use I’ve finally got round to recapping. I’d also like to check and set the bias current but am scratching my head slightly. The service manual instructions are to set at 60mA measured at point “I” on the schematic which is collector of two of the AD149 transistors… which doesn’t look to be anywhere accessible ?? There’s a bundle of wires that head towards the output transistors on the front edge of bottom of the case but I can’t see anywhere to tap into the wires that would be point “I”.
Later “black key” versions of the Beomaster 1000 I’ve worked on (obviously wholly different as they are Silicon transistors rather than the Germanium mine has) instead give a voltage to check across a resistor that would be the equivalent of the 0.47 Ohm (691) in the snippet of the schematic. But current at collector and emitter are not going to be the same so I don’t have a value for voltage that I could set the bias to on my type 2301.
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