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Old 15th Jan 2018, 11:46 pm   #26
ms660
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Join Date: Apr 2011
Location: Cornwall, UK.
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Default Re: Hitachi SR-302 light bulb identification

Quote:
Originally Posted by ms660 View Post

EDIT: Might have sussed it now.

Lawrence.
Doing the R channel:

S6b is the reverse side of S6a wafer but viewed "through" S6A, the bottom two contacts of S6B are connected to the bottom two contacts of S6A so both of the LH ones are connected to speaker terminal A+ and both of the RH ones are connected to the R channel.

S6A (and thus S6B) are shown in the off position, first position clockwise is position A, S6A wiper connects speaker terminal A+ to the R channel, S6B doesn't connect anything to anything.

Next position clockwise is position B, S6A wiper breaks contact with speaker terminal A+ and connects speaker terminal B+ to the R channel, S6B wiper connects to the R channel contact only.

Next position clockwise is position A+B, S6A wiper still connects to speaker terminal B+, S6B wiper connects speaker terminal A+ to the R channel, net result is A+B connected in parallel to R channel.

Next position clockwise is headphones only which is self explanatory.

.....I think.

Lawrence.
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