Hello, Really need some help here if anybody can. Bought a Sorado on ebay. Have seen several configurations of the chassis. Mine has two 6550's right in front when you open it up, a transformer at either end, and two smaller tubes. One is in the far right corner behind one of the transformers. The other is behind the power tubes. But right in the middle of the chassis, near the grill cloth is a hole about one inch diameter with a couple of screws around the outside of it. One schematic I have seen shows a capacitor there, but no tube in the far corner. Another seems to show no hole there at all.
When I plugged the amp in, it played fine for about 20-30 minutes, then blew the fuse. Now it immediately blows every new fuse I put in it. I have been advised that if the 6550's are bad, it will blow fuses. So I have a two part question. Most importantly, is anything supposed to be in that hole, or was there "generic" hole-drilling in the chassis? And if the chassis is correct, why am I blowing fuses ?
The tag with the serial number is partially worn away. It reads MMX45502. The "X" appears to be either an 8, a 9, or a 0. That's my best guess. The owner said it was from 1969, and played well last time he used it, 3 years ago! It has groove tubes, which I have not been able to have tested yet. Since the fuse blows immediately, I can't now tell if they even light up.
Any and all suggestions would be appreciated. Thanks much
