Nashville Electronics Cap Question

[Ismellelephant]

Been a while since I've been here, but I am now retired and trying to fix a Sherwood S 5000 II 80 watt amp. I am hoping someone might be familiar with this cap
It is a multicap, a Nashville Electronics 300mfd 50v cap. I don't fully understand the pinouts. One bare lead was soldered to chassis, the other bare lead to a couple of diodes and a 22 ohm resistor, and the black lead to a 1k resistor, the 1k resistors other end to the bias pot, and blu/wht transformer lead. The cap is bad, the only reading I could make was from the black lead to the bare lead that goes to the diodes and a 22 ohm resistor. Using a multimeter I got 59uf. I have a schematic but I can't find this cap in the schematic. Does anyone know the pinout for this cap? Not sure what I need for a replacement or how to wire it back up. Thanks for any help.

 

[century tek]

Was it bad to begin with? Looks like it has 3 individual capacitors inside one can. Pretty simple. All the outer lugs are ground so the can itself is common negative. According to what I see in your pics, all 3 wires are 300 MFD (µf) @ 50 volts. On your schematic, it would be labeled something like C1A, C1B, C1C for the 3 capacitors inside.

You can either search down a single can capacitor, or use 3 individual capacitors if there is room underneath for whatever you are working on.

Boy I gotta tell ya, and please don't take offense , but if you didn't know what a simple can capacitor looked like, what's inside, or be able to interpret the writings, I think I would leave it to someone else who knows what they are doing. It's easily repairable but if you didn't know what the wires were or where they went to, you would have a doorstop.

 

[zackthedog]

Been a while since I've been here, but I am now retired and trying to fix a Sherwood S 5000 II 80 watt amp. I am hoping someone might be familiar with this cap
It is a multicap, a Nashville Electronics 300mfd 50v cap. I don't fully understand the pinouts. One bare lead was soldered to chassis, the other bare lead to a couple of diodes and a 22 ohm resistor, and the black lead to a 1k resistor, the 1k resistors other end to the bias pot, and blu/wht transformer lead. The cap is bad, the only reading I could make was from the black lead to the bare lead that goes to the diodes and a 22 ohm resistor. Using a multimeter I got 59uf. I have a schematic but I can't find this cap in the schematic. Does anyone know the pinout for this cap? Not sure what I need for a replacement or how to wire it back up. Thanks for any help.

It looks like a replacement with three caps stuffed in a can and sealed with resin. Looking at the schematic it seems it was meant to replace C60, a three-terminal can cap. Here are some good pix of a stock S-5000 II, perhaps these will help you figure out what was replaced and what should be there:

http://audio.rdsrepair.com/sherwood-s-5000-ii.html

 

[Ismellelephant]

Actually I am a retired electronic tech but mostly worked on SMD stuff under a microscope. I have repaired many guitar tube amps and not totally clueless, lol. But I appreciate the cautionary intent. I just hadn't seen this cap before and one bare lead that appeared to be positive was soldered to chassis ground. But a private messaged informed me that this cap, being involved in the bias circuit, it was not unusual to have a cap's positive lead at ground potential. The private message also supplied a more accurate schematic of this amp and I now see this cap in the bias circuit. On the schematic I had I couldn't find the bias circuit at all. BTW think there are two 300 mfd 's in this package. Two bare positive leads, one negative black lead as shown in dotted box on attached schematic.
All the other can caps leads were clearly marked and appear ok but would be replaced as I go along. One other 120 mfd paper cap is being replaced along with this 300 mfd as a starting point. This amp is actually in pretty good shape, I also have same era receiver. So far I found a couple of disconnected wires and it needs new 7868 tubes. I bought EH7868's which have larger diameter pins so socket changes might be necessary at the very least.
Thanks for the responses.

 

[gadget73]

Looks like a 2 section with a common positive. Common positive to chassis, the two individual negatives go where they go. One to the diode, one to the tube heater, and the 22 ohm sits between the sections. I'd sub that with a pair of 330uf 50v on a terminal strip and call it good. Stick the original can back in the hole to make it look right.

 

[Ismellelephant]

Thanks for all the help. This amp is now working and sounds good to my old ears. Any tips or suggestions on selling this amp and working untouched S2100 receiver? I am more of a old guitar amp guy and would like to get this into the hands of someone that could do these items justice. Any info is greatly appreciated.