View Single Post
Old 10-31-2021, 04:39 PM   #6
R_J
Badcaps Veteran
 
Join Date: Jun 2012
City & State: ☻
My Country: Canada
I'm a: Professional Tech
Posts: 8,146
Default Re: Motor control board

It's nice top know one is getting warm, it would be nicer to know WHICH ONE? I will guess and say the +15 is getting warm and the -15 is not.
If both components have the same numbers it is unlikely they are both positive and negative voltage regulators

Do both regulator ic's have a common ground? have you checked the IN on the -15 ic to see if it has any voltage?
The transformer secondary is likely center tapped and the center tap goes to ground, and one part of the winding supplies each ~ on the bridge rectifier, then the + of the bridge supplies the positive IN for the +15v regulator and the - of the bridge supplies the negative IN of the -15 volt regulator

Last edited by R_J; 10-31-2021 at 04:53 PM..
R_J is offline   Reply With Quote