Brandon,

If both tolerances were at the wrong end, it's called "a defect in
materials or workmanship". Both ends of the tolerance are supposed
to be within the design limits.

It looks like your unfortunate accident has started a whole new
set of workarounds, and at the risk of being labeled a Meade Basher,
if you have to develop a workaround for a fuse, there's something wrong.

Dave

The circumstances have to be understood to cover the situation I have had
and several others over the the years. The current loading on the fuse
creeps up slowly as the motor loading goes up over a long period of time
consequently the motor can self destruct before the fuse. It is the 2 cents
fuse against the 200 dollar motor.Fuses are great where there is a clear cut
failure of a current surge over a short period of time that blows the fuse
and saves the day.Jam your gearbox solid and hopefully the fuse will blow
and save everything. Ok why a 200 dollar motor . The motor is part of a
gearbox that can not be dissassembled without special tools and knowledge.
The motor is also unique to the electronics of this circuit to give optimum
performance.Yes the motor is worth about 2 dollars and for five you could
get a motor that is about five times better quality.Unfortunately without
re-calculating the components in the bridge circuit that controls it it
would not necessarily respond properly. These calculations also relate to
the internal resistance of the motor its inductance and the revs achieved
for current and voltage input under load.You would pretty well have to have
a very similar motor as a replacement. I originally myself stripped my
gearbox and fitted another motor when told that meade would not supply
one.It worked but not good enough.I tried asecond and had similar problems.
In the End I had to buy a complete gearbox and motor assembly. You guessed
it cost 200 dollars not the 500 dollars I had previously been miss quoted. I
replaced the whole lot after machining the motor mounting plate. The reason
for this is that I had been supplied the wrong one and I did not want to
send it back. The scope is now working perfectly.I have to admit that I
learned a lot about stripping Meade gearboxes and I also admit that this is
an unusual problem but the real pain has been the frustration and the time
wasted over it all becaus of the inadequacy of a 2 cent fuse in this case.

Brandon S. Jones

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