Re: tube amp blows fuse

effi@xxxxxxx said:

>if the 6ca4 is the only tube plugged in the fuse blows immediately when
>the unit is turned on


It is possible that the 6CA4 (EZ81) developed a short between
electrodes, presumably the heater and one of the anodes.
You can replace the tube, or use 2 1N4007 silicon diodes with series
resistors of about 47 ohm/5 watts instead.

I suspect the supply caps will be OK, since the fuse blows
immediately. If they weren't, the fuse would only blow after warming
up of the 6CA4.

--

"Audio as a serious hobby is going down the tubes."
- Howard Ferstler, 25/4/2005
.

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