Fuses Blowing [resolved]

ALL212 · 1418

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Offline ALL212

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on: May 23, 2015, 10:00:52 AM
Figured I'd put this here instead of a new thread.   :-[  I've messed the voltage gods and they are killing my fuses!  Had the o'scope out and was just prodding around.  No snaps, no pows, no sparks - she suddenly just powered down.

Resistance checks good except 6 and 10 are straight to ground., 7 and 9 are good.  Fuse blows on power up.

Help!
« Last Edit: May 23, 2015, 11:33:50 AM by Caucasian Blackplate »

Aaron Luebke


Offline Paul Birkeland

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Reply #1 on: May 23, 2015, 10:03:53 AM
Which terminals were you probing with your scope?  What kind of fuses are you using as substitutes?

The 0 Ohms at 6/10 would indicate that you have modified the jack with the ground shorting modification.

Paul "PB" Birkeland

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Offline ALL212

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Reply #2 on: May 23, 2015, 10:11:43 AM
 :-[

I've angered the voltage gods and they are sacrificing fuses.  I had the oscope out and was prodding around - but no snaps, pops, sparks or smoke.  She suddenly just powered down.  Fuse blows on power up.  I'm using a .5a fuse.

All resistances are good and I have no signs of burnage or damage anywhere.

I've gone through all my .5 fuses but have a pack of 1.5's - not going there unless told to.

Help?

Aaron Luebke


Offline Paul Birkeland

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Reply #3 on: May 23, 2015, 10:45:41 AM
A 1.5A fuse is OK for testing purposes.  0.5A fast fuses may be the problem to begin with.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline ALL212

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Reply #4 on: May 23, 2015, 11:28:05 AM
Yes, I did the jack grounding, looked at the schematic for minute or two then realized what that issues was after my first post.  I put in one of those 1/4" to little adapters to spread the contacts and got the right resistance.

I'll snap the 1.5's...oh, they are 1.25's, no problem.

I've got heaters!!  I'll do the voltage checks just to make sure I didn't muck something up.

Sorry for the double post - I think I missed that you moved it and reposted as you moved it.

Thank you!

Voltage checks all good.  OK to leave the 1.25a fuse in?
« Last Edit: May 23, 2015, 11:38:48 AM by ALL212 »

Aaron Luebke