[ Nevin Engle wrote in 120106:
> The 12 ampere fuse in the bottom was blown but none of the others.
> ... As soon as the 'on' switch is depressed the fuse blows again.
> What is the likely culprit?
Hi All, Blowing out a 12 ampere fuse indicates a significant short
circuit. I'm surprised you can't see (or locate) a part in the system
that looks overheated or charred.
One of the first things you learn as an electronics technician is
"don't replace a blown fuse and try it again until you've located the
problem." The correct step to take after a large fuse has blown is
to examine the schematic and determine which components in the system
could possibly short and cause the large fuse to blow. Then you test
those components with an ohmmeter.
If you don't have the schematic drawing, or don't know how to read it,
or don't have an ohmmeter, you're not qualified to work on the device.
Be that as it may, I have sent the wiring diagram for the Wurlitzer 1203
to Robbie so he can put it in the technical section of the MMD web site.
Frankly, as electrical systems go, the Wurlitzer isn't that complicated,
and, looking at the schematic, the first thing I'd check are the diodes
in the DC power supply.
Musically,
John A Tuttle
Player-Care.com
Brick, New Jersey, USA
[ Look for the drawings under "Schematic Diagrams & Drawings" at
[ http://www.mmdigest.com/Gallery/Tech/index.html -- Robbie
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