Hi   I have an Audio research D250, its a wonderfull amp even though it eats a fortune of tubes and produce to much heat to be used in the summer. I have changed all the tubes and have done all the adjustments except "Ac balance" and now I need your help.   The manual says I should...

Hi   Im troubleshootinng my dead audio research Ls17 (cat pee). I found that the primary winding on a small transformer is burnt: The transformer supplys the control panel. It´s marked 60013614B on the top and 0630 on the side.   The transformer is supplied with 240V on the primary...

Hi   I have just discovered how fun it is to build an modify amps and Im planning to get moore serious with it. I want a good pc based oscilloscope to measure THD bandwith and so on. I guess it would help if the scope has a signal generator.   Ivé been looking at the picoscope 2200 and...

I found an old transformer it´s marked Noise protection transformer 3000VA. Can I use this transformer to my amp thats conected to the computer without connecting the computer to the transformer? Do I need a ground loop insulator? Here´s a scheme of the transformer made in paint ...