Lawrence writes:

A friend has a Dremel model 1680 16 inch variable speed scroll saw. The
motor started working intermittently and shortly after that it stopped
working completely. The motor itself is fine since if the power is wired
directly to it the saw will run with no problem. This means the fault is
on the speed control circuit board. The problem with this is the fact
that Dremel has sanded off the part numbers on the two IC's on this
board so we have no idea just what they are or what the pinout would be.
Does anyone know where I might locate a schematic of this board so I can
troubleshoot it and see what the problem is? Or, if someone out there
has one of these puppies that has a fried motor and they want to part
with the speed control circuit board then let me know and I will pass
the info along to my friend. Thanks in advance.

Have you checked for bad solder connections?

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
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