Amp used for the first time, in 2 years of regular mains use, with a
generator. Works fine with no problems. Coincidence ?, next gig back to
usual mains supply, at power up, blows the mains fuse. The GZ34 is failed
both sides, 0 percent output . Inspecting the fuse it has failed at an end ,
not the central (T) section and otherwise complete wire shows no sag or
discolouration. So possibly mechanical failure of fuse. If fast make/break
intermittant action of the fuse wire at an end , would that knock out an RR
valve? What in general happens in the failure of RRs ? I've only ever seen
75 percent , same as new, or 0 percent "goodness" at prescribed current
settings of the Avo valve tester.