In Reply to: RE: St70 bias resistor posted by Steve Franklin on December 13, 2014 at 08:30:34:
I think the original 1W 15.6Ω was wirewound, but I do not know why. Maybe it was a more convenient way to get a 1% value in those days. If we're talking about a slightly modified version of the original biasing scheme in the Stereo 70, then we're talking a 1VDC drop across a 10Ω resistor at idle:1VDC = I * 10Ω
I = 100mAP = 1VDC * 100mA
P = 0.1WMaybe the resistor needs to be able to dissipate more power under dynamic conditions, I don't know. But, to be able to set the bias accurately, you probably want to make sure the resistors measure within 1% of value, however you can get that accomplished.
Anyone, please feel free to correct my math if needed.
Edits: 12/13/14 12/13/14 12/13/14 12/13/14
This post is made possible by the generous support of people like you and our sponsors:
Follow Ups
- RE: St70 bias resistor - petercapo 10:12:59 12/13/14 (1)
- RE: St70 bias resistor - Steve Franklin 13:14:17 12/13/14 (0)