On Jan 23, 8:59*pm, John Robertson wrote:
em pinball wrote:
I was working on my ami e-120 when i shorted the credit light out.
blew a fuse. replaced fuse and when i plugged it in the transformer
started to smoke. besides my stupidity can someone tell me what would
cause the transformer to smoke. i have another transformer that shows
36 volts coming out of it but want to make sure i dont have something
else wrong before i install it. thanks in advance norm

Check if the bridge rectifier is shorted. Often people replace the
original Selenium Bridge Rectifier (has green plates stacked on a shaft
and the AC/DC leads are soldered to lugs sticking out from the centre
shaft) with a more modern Silicon Bridge Rectifier (usually a black
square with four lugs sticking up), however they do not fuse the AC side
of the new bridge...leading to transformer failure if/when the new
bridge shorts out!

Fuse the AC lead to one side of the bridge (assuming this in NOT a
center-tapped transformer - in which case BOTH AC leads are fused with
1/2 the value just below) with a slo-blow fuse no larger than the total
current of the fuses that split from that circuit - a 1A and a 1A5 fuse
I think, for a total of 2A5 (read that as 2 point 5 Amp) slo-blow fuse.

There is also an Electrolytic Capacitor in the metal box that needs to
be checked for a short circuit...

John :-#)#

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i replaced the cable from the junction box to the carriage box,
replaced the switch on the tone arm cam and the rectifier. got it
working retty good now. problems no are in my button selectors. not
many work. thanks for the help norm