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Old 30th Sep 2021, 10:15 pm   #3
Graham G3ZVT
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Join Date: May 2010
Location: Greater Manchester, UK.
Posts: 18,676
Default Re: singer 2502c pedal repair

Quote:
Originally Posted by M3VUV51 View Post
would i possibly be correct in thinking the caps have gone low capacitance causing ing the diac to conduct faster hence switchind the triac to fully on faster hence no ramp up on the speed control? tia m3vuv.
Possibly, but I would suspect the BT134 first.
Check for a short between MT1 & MT2

Looks like they've used a 500v type, replace it with a BT134-600 or 800
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