Hey everyone,
I like the general build of the Yaqin MC100B, but I am less impressed by its input selector an dvolume pot. Space inside is a bit cramped, so I'm considering turning it in to a power amp.
Since the front input is rated at 0.6V, it appears useful to use this input.
Looking at the schematic, the only thing the switch looks like it's doing is putting R1 (150 Ohm) and R2 (330 Ohm) in parallel over R3 (can't read the value on the schematic 1K2 ?) (bonus question : what is this madness with R1 and R2 ? Why not use a 75 Ohm and be done with it ) (bonus 2 : what is that R5 39K doing there ?)
All that would then remain is simply rip out the volume pots, which for no obvious reason are still active when you use the front inputs.
Or would I be better served by upgrading the volume pot and building a relay input board ? And doing away with that input switch alltogether ? (Incidentally, I don't see the point of it. Any clues anyone ?)
I've considered selling it but there does not seem to be a lot of interest except from lowballers, so I'll keep it.
Thanks,
Pete
I like the general build of the Yaqin MC100B, but I am less impressed by its input selector an dvolume pot. Space inside is a bit cramped, so I'm considering turning it in to a power amp.
Since the front input is rated at 0.6V, it appears useful to use this input.
Looking at the schematic, the only thing the switch looks like it's doing is putting R1 (150 Ohm) and R2 (330 Ohm) in parallel over R3 (can't read the value on the schematic 1K2 ?) (bonus question : what is this madness with R1 and R2 ? Why not use a 75 Ohm and be done with it ) (bonus 2 : what is that R5 39K doing there ?)
All that would then remain is simply rip out the volume pots, which for no obvious reason are still active when you use the front inputs.
Or would I be better served by upgrading the volume pot and building a relay input board ? And doing away with that input switch alltogether ? (Incidentally, I don't see the point of it. Any clues anyone ?)
I've considered selling it but there does not seem to be a lot of interest except from lowballers, so I'll keep it.
Thanks,
Pete
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