I am repairing (tryin to any way) a Sunn Alpha 112 amp for a friend. The amp is completely dead. The only action is when you turn the power switch on, the light (neon bulb I think) in the power switch lights up. I tried connecting a patch cable from the accessories to and from jacks and also tried connecting headphones to the headphone jack and still no sound. There is no humming and no thump when you turn the power switch on. I've tried setting the output knob to various settings and the drive knob to various settings. I have disassembled the amp enough to unseat the control panel and stand it on end on top of the amp with the speaker still connected. There are three fuse holders on the circuit board. F1 is in series with the 110V AC input. F2 and F3 are in series with the + and (-) outputs of the bridge rectifier circuit, respectively. However, the F2 and F3 fuse holders have NO FUSES INSTALLED!! Seems odd but I thought I'd ask here if this may be some oddball normal configuration. At first I thought F1 (1.5A 250V Slo-Blo) was blown as the glass was cloudy but my ohm meter says zero ohms. But there is a black wire that connects to the circuit board next to this fuse holder and the end of it looks like it is melted from getting too hot. While I was reinstalling F1, this wire came loose from the circuit board, leaving a miniature cone of what looks like milky white epoxy. Any ideas?
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