I have removed the circuit boards from the cabinet found a cap that has blown one of the terminals off . I am not familiar with the cap wirering but on the cap it is written the ground side of the cap goes to the black wirer . This cap does not have a black wirer but there is a black dot on the terminal is this the ground
I will post photos of the board and a printed circuit.
I do not know which circuit is the one i am looking for
The black dot on the capacitor is the negative. However that may not be ground. Most amplifiers have both positive and negative power supplies. I think that your one has +24 V and -24 V supplies, so the capacitor will have its negative connected to -24V and its positive connected to ground, and another identical capacitor will have its negative connected to ground and its positive connected to +24 V.
A better picture of the top right hand corner of the circuit diagram would help. That is the power supply part of the diagram.
With an amplifier of that age, change all the electrolytic capacitors. Many repairs of much younger electronics involve changing the capacitors as they degrade with time and they are often far below rating after a decade or two. The large ones are the most important, but by the time that you have paid for those, the smaller ones will be a small fraction of the price.
A replacement capacitor will be marked differently, because capacitor marking has changed since that amplifier was built. Modern ones may be a lot smaller. On the big electrolytic capacitors, having a larger voltage and capacity than what you had before will only be an advantage.
You're perhaps too young?, split supplies are a relatively 'recent' innovation - and this amp uses a single supply, as they all did back then.
However, as regards this amp, they weren't a great amp, and weren't highly regarded - once fixed it's OK as a historical curiosity, but not really as a 'wonderful sounding amp' from olden days.
I'm not too young for anything. I've used slide rules, mechanical calculators, and my first use of a computer was via a teletype and a modem with a rotary dial phone, programmed off-line by storing the code on paper tape.
Back to the amplifiers, I missed out on repairing any reasonably-sized amplifiers until this century, so I thought that most larger amplifiers would have split power supplies.
I'm not too young for anything. I've used slide rules, mechanical calculators, and my first use of a computer was via a teletype and a modem with a rotary dial phone, programmed off-line by storing the code on paper tape.
Back to the amplifiers, I missed out on repairing any reasonably-sized amplifiers until this century, so I thought that most larger amplifiers would have split power supplies.
All the 'classic' amps like Quad and Leak were single supplies, the technology didn't really exist yet for split supplies (lack of high power PNP as much as anything else).