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Author Topic: Fuse blown during use  (Read 237 times)

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Offline slm

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Fuse blown during use
« on: May 08, 2017, 11:17:08 pm »
Hi All

Kaiju has been singing since january and last night fuse blew during use . Pulled tubes and performed some resistance checks and found 6.2 ohms from terminal 37 to 38 . also zero ohms across diode on 38l . That doesn't seem right ? is that diode and capacitor gone down - is it likely cap shorted and took out diode ?

Do I just replace both ? is it likely to have damaged anything else ?

Thanks in advance

Simon

Offline Caucasian Blackplate

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Re: Fuse blown during use
« Reply #1 on: May 12, 2017, 11:04:42 am »
Did you try replacing the fuse and turning the amp back on?

If a diode is "gone", especially if it is shorted, you will know because it will explode and there won't be anymore diode in your amplifier.   Capacitors are much the same!
Paul "PB" Birkeland

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Offline slm

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Re: Fuse blown during use
« Reply #2 on: May 12, 2017, 01:02:41 pm »
Yes tried again and fuse blew instantaneously . That was the only screwy measurement I could find . Visually they look normal . Not sure how else to investigate cause ?

Offline Doc B.

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Re: Fuse blown during use
« Reply #3 on: May 12, 2017, 01:34:58 pm »
Disconnect the rectifer diode from 38, then measure its resistance from one end to the other, without being connected to the cap. That will tell you if the rectifier failed or the cap.
Dan "Doc B." Schmalle
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