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Fisher 170 Distortion
#26

Or another way, I simply would connect a scope and, while feeding the amp a sinewave, bring the idle while the crossover "step" disappeared.
If you feel the idle is too much, then bring it down a notch, as long as you cannot hear the step or it is barely noticeable on the scope.

There is a nice arrangement on an amp I built long time ago for myself with self-limiting of idle using feedback, I could set it as large as 300mA and there would be no thermal runaway.
An old and less efficient way to control the runaway is a thermistor in parallel with the trimpot that is mounted on heatsinks.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.


Messages In This Thread
Fisher 170 Distortion - by Ron Ramirez - 07-19-2014, 10:50 PM
RE: Fisher 170 Distortion - by morzh - 07-19-2014, 11:14 PM
RE: Fisher 170 Distortion - by Ron Ramirez - 07-19-2014, 11:18 PM
RE: Fisher 170 Distortion - by morzh - 07-19-2014, 11:20 PM
RE: Fisher 170 Distortion - by morzh - 07-19-2014, 11:26 PM
RE: Fisher 170 Distortion - by Mondial - 07-20-2014, 12:39 PM
RE: Fisher 170 Distortion - by morzh - 07-20-2014, 02:42 PM
RE: Fisher 170 Distortion - by codefox1 - 07-20-2014, 07:33 PM
RE: Fisher 170 Distortion - by Ron Ramirez - 07-21-2014, 11:38 AM
RE: Fisher 170 Distortion - by morzh - 07-21-2014, 03:08 PM
RE: Fisher 170 Distortion - by Ron Ramirez - 03-19-2015, 08:06 PM
RE: Fisher 170 Distortion - by Mondial - 03-19-2015, 08:46 PM
RE: Fisher 170 Distortion - by Ron Ramirez - 03-19-2015, 09:37 PM
RE: Fisher 170 Distortion - by Mondial - 03-19-2015, 10:40 PM
RE: Fisher 170 Distortion - by Ron Ramirez - 03-20-2015, 08:23 AM
RE: Fisher 170 Distortion - by Mondial - 03-20-2015, 08:48 AM
RE: Fisher 170 Distortion - by Ron Ramirez - 03-20-2015, 08:56 AM
RE: Fisher 170 Distortion - by Ron Ramirez - 03-20-2015, 11:26 AM
RE: Fisher 170 Distortion - by Mondial - 03-20-2015, 12:20 PM
RE: Fisher 170 Distortion - by morzh - 03-20-2015, 12:27 PM
RE: Fisher 170 Distortion - by Ron Ramirez - 03-20-2015, 04:42 PM
RE: Fisher 170 Distortion - by morzh - 03-20-2015, 05:06 PM
RE: Fisher 170 Distortion - by Ron Ramirez - 03-21-2015, 04:30 PM
RE: Fisher 170 Distortion - by morzh - 03-21-2015, 05:03 PM
RE: Fisher 170 Distortion - by Mondial - 03-21-2015, 07:30 PM
RE: Fisher 170 Distortion - by morzh - 03-21-2015, 09:15 PM
RE: Fisher 170 Distortion - by Ron Ramirez - 03-21-2015, 10:31 PM
RE: Fisher 170 Distortion - by morzh - 03-21-2015, 10:51 PM
RE: Fisher 170 Distortion - by Mondial - 03-21-2015, 10:51 PM
RE: Fisher 170 Distortion - by Ron Ramirez - 03-22-2015, 01:40 PM
RE: Fisher 170 Distortion - by morzh - 03-22-2015, 02:47 PM
RE: Fisher 170 Distortion - by PhilcoMike - 03-23-2015, 03:21 PM
RE: Fisher 170 Distortion - by Ron Ramirez - 03-23-2015, 04:31 PM
RE: Fisher 170 Distortion - by Ron Ramirez - 01-23-2016, 06:08 PM



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