I picked up a nice, clean 2225 last month off CL and it plays/sounds great. Last night I replaced the dial and meter bulbs with blue LEDs from Parts Express. And that results turned out really nice. See before and after pix.
I then set about checking/setting Power Amplifier and Power Supply adjustments and was able to dial in everything except the J712(+)/J718(-) and J713(+)/J719(-) adjustments to 20 mV per the Service Manual. The closest I could dial in was down to 60 and 63 mV respectively. DC offset at speaker terminals is 3 mV and 1.5 mV.
History: Looking over all the boards it is obvious someone has already replaced all the electrolytic caps on all boards, including the amplifier board. And I have yet to verify that all the new caps are properly sized replacements.
So other than wrong cap somewhere, why else might I not be able to dial in the proper 20 mV? Bad trimmer pots maybe?
I then set about checking/setting Power Amplifier and Power Supply adjustments and was able to dial in everything except the J712(+)/J718(-) and J713(+)/J719(-) adjustments to 20 mV per the Service Manual. The closest I could dial in was down to 60 and 63 mV respectively. DC offset at speaker terminals is 3 mV and 1.5 mV.
History: Looking over all the boards it is obvious someone has already replaced all the electrolytic caps on all boards, including the amplifier board. And I have yet to verify that all the new caps are properly sized replacements.
So other than wrong cap somewhere, why else might I not be able to dial in the proper 20 mV? Bad trimmer pots maybe?
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