Mixed report:
- When the oilcan effects are off, I get beautiful, dynamic, noise/distortion-free tone.
- The Reverb and Tremolo effects sound great.
- I bought a Tektronix 465B oscilloscope, a Lambda triple DC power supply, and a Fluke bench meter.
- I built a custom 4-switch foot pedal with parts from Home Depot - works great!
- The oilcan effects are noisy. There is a regular pop, synchronous with the rpm of the Rotating Sound motor, that can be heard even if the Rotating Sound effect is off. It can be heard when either the delay or the rotating sound effects are on at all, and gets louder as these effects are turned up.
- There is some noise that I can hear and see on my scope when the effects are on. It is (in addition to the cyclical pop) very high frequency, and sounds like static/grounding noise. I have replaced all of the components on both of the two amp cards mounted to each motor, with no noticeable effect.
- The Long Delay setting yields unimpressive results compared to the Short and Multiple settings. The long delay send wire that comes from the selector switch was broken off. It looked like the break had happened at the top (backmost looking at the amp), two pins away from the input wire. There are a few caps and resistors wired into this messy switch - doeas anyone have a hi-res picture of this switch wired properly? The scematic I have differs from the electronics inside - not sure if it's been modded or if it's just a different version.
I have completely disassembled both motor assemblies, inside and out, and meticulously cleaned everything right down to the screws and washers (used up two toothbrushes, five 00 brass wool pads, a brass brush, a steel brush, and more than 1000 two-sided Q-tips (no joke)). In fact, in addition to cleaning, resurfacing, and polishing literally everything, I also resoldered every connection in the entire amp. I replaced the power transistors, all of the electrolytics, the power resistor (which was killed by one of the original(? 22-3773) power transistors that shorted out), and completely restored the hardware, skin, and the crumbling original wooden deck. She looks like new! Again, I've got over 150 pics if anyone's interested . . .
In fact, playing through the clean channel, or the effects channel with both the Echo and Rotating Sound effects off, it drives an 8 Ohm 12" or a 4 Ohm 15" beautifully. This tells me that the preamp and power amp are clean and fine. All of the components on the can-cards are new, and still test ok taking them out of the circuit. The insides of the cans were completely disassembled and cleaned, and 20 ml of special-order oilcan oil was added. I put new belts on. Could the AC motors just be tired/old and leaking noise?
Anyone have any guesses/ideas/inklings? I'm out, and really excited to have that "AHA" moment worth 2000 Q-tip swabs.
My last idea is to replace the 2-prong AC plug/wire with a proper, three-prong, grounded set. There's no harm in doing this is there?
Thanks for all the help, this Supernova may as well have been called the Odyssey!
- When the oilcan effects are off, I get beautiful, dynamic, noise/distortion-free tone.
- The Reverb and Tremolo effects sound great.
- I bought a Tektronix 465B oscilloscope, a Lambda triple DC power supply, and a Fluke bench meter.
- I built a custom 4-switch foot pedal with parts from Home Depot - works great!
- The oilcan effects are noisy. There is a regular pop, synchronous with the rpm of the Rotating Sound motor, that can be heard even if the Rotating Sound effect is off. It can be heard when either the delay or the rotating sound effects are on at all, and gets louder as these effects are turned up.
- There is some noise that I can hear and see on my scope when the effects are on. It is (in addition to the cyclical pop) very high frequency, and sounds like static/grounding noise. I have replaced all of the components on both of the two amp cards mounted to each motor, with no noticeable effect.
- The Long Delay setting yields unimpressive results compared to the Short and Multiple settings. The long delay send wire that comes from the selector switch was broken off. It looked like the break had happened at the top (backmost looking at the amp), two pins away from the input wire. There are a few caps and resistors wired into this messy switch - doeas anyone have a hi-res picture of this switch wired properly? The scematic I have differs from the electronics inside - not sure if it's been modded or if it's just a different version.
I have completely disassembled both motor assemblies, inside and out, and meticulously cleaned everything right down to the screws and washers (used up two toothbrushes, five 00 brass wool pads, a brass brush, a steel brush, and more than 1000 two-sided Q-tips (no joke)). In fact, in addition to cleaning, resurfacing, and polishing literally everything, I also resoldered every connection in the entire amp. I replaced the power transistors, all of the electrolytics, the power resistor (which was killed by one of the original(? 22-3773) power transistors that shorted out), and completely restored the hardware, skin, and the crumbling original wooden deck. She looks like new! Again, I've got over 150 pics if anyone's interested . . .
In fact, playing through the clean channel, or the effects channel with both the Echo and Rotating Sound effects off, it drives an 8 Ohm 12" or a 4 Ohm 15" beautifully. This tells me that the preamp and power amp are clean and fine. All of the components on the can-cards are new, and still test ok taking them out of the circuit. The insides of the cans were completely disassembled and cleaned, and 20 ml of special-order oilcan oil was added. I put new belts on. Could the AC motors just be tired/old and leaking noise?
Anyone have any guesses/ideas/inklings? I'm out, and really excited to have that "AHA" moment worth 2000 Q-tip swabs.
My last idea is to replace the 2-prong AC plug/wire with a proper, three-prong, grounded set. There's no harm in doing this is there?
Thanks for all the help, this Supernova may as well have been called the Odyssey!