In Reply to: Fisher 80AZ zmatic posted by stltrains on April 19, 2011 at 18:06:20:
Quite possible that there's a oxide film on the switch contacts so that an ohmmeter won't make it conduct - wouldn't be a problem on a power switch, as 117V would instantly burn it away. Anyway, the grounded end of the pot is the same as "off" anyway.
How it works: the negative feedback is a combination of voltage feedback (from the 16 Ohm terminal) and current feedback (the drop across a sample resistor, with three settings for 4, 8, 16). Voltage feedback lowers output impedance, curent feedback raises it, so the variable mix of the two can give any desired output Z. Most modern speakers are designed to work with low source impedance, so you'd probably leave it at zero.
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Follow Ups
- RE: Fisher 80AZ zmatic - Tom Bavis 07:30:55 04/20/11 (2)
- RE: Fisher 80AZ zmatic - stltrains 18:02:50 04/20/11 (0)
- RE: Fisher 80AZ zmatic - PakProtector 08:56:19 04/20/11 (0)