A B- Question On My 46-250 - Printable Version

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A B- Question On My 46-250 - Johnny - 06-18-2009

Yes me again. This time I don't see any notes that I'm missing.

The black wire coming out of the Z300 transformer finds its way down to pin 7 of the 7C6 2nd detector/1st audio on the schematic. According to the schematic pin 8 of the 7C6 is B- and is common to pin 7 of the 7C6. So are pins 7 and 8 of the 7C6 common to each other?

Thank you,
Johnny

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Re: A B- Question On My 46-250 - exray - 06-18-2009

Yes. And Pin 4 is also common to them.

Here's what you missed Or rather what the draftsman missed. Down at the bottom of the drawing where the tube filaments are shown connected in series the tubes are not labelled but the 7C6 would be the last one in the string closest to ground. Its standard procedure to have the detector tube as being the one 'closest' to ground in a series string so as to minimize hum.

http://www.nostalgiaair.org/PagesByModel/592/M0013592.pdf

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