Mark III+ blowing fuses

Mark I's, II's, III's and the almight IV

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Mark III
Posts: 212
Joined: Wed Jan 31, 2018 8:32 am

Re: Mark III+ blowing fuses

Post by jrb32 » Thu Jan 24, 2019 5:15 am

As I said before the cheapest way of testing without buying any more equipment unnecessarily would be:

Go back to John Kelly and take your stepdown transformer with you this time.

Get him to test it. If it gets really hot with your stepdown transformer and blows a fuse, and it doesn't with his (the one he originally tested it on), then obviously there is some kind of weird incompatibility going on with your stepdown transformer. Easy. Simple. 100% confirmed.

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Posts: 387
Joined: Thu Jul 09, 2009 1:41 am
Location: Canberra, Australia

Re: Mark III+ blowing fuses

Post by McBarry » Tue May 07, 2019 3:41 am

Totes agree with Woodbutcher65 re caps..
ALSO check the Sprague on the B+ to ground - it's mounted near the power tubes.
And if the ground polarity switch is in use, the Sprague attached to it would immediately be suspect..

Keep us posted, esp for future readers.. Cheers, Dave
Mk I,export,GEQ,cream
Mk IIA,exp,rev,cream
Mk IIB,exp,rev, tweed
Mk IIB,exp, rev,GEQ,simul, black
Mk III head,rev,GEQ,cream
Mesa Studio 22+, fan
Kitty Hawk M1 head
Fender 75, exp, 1973,15".
Fender 6G6A Bandmaster 1962
Fender AA763 Bandmaster 1964

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