Dual 18 volt 5 amp power supply

[argonrepublic]

I have a mixing console that requires +/- 18 vdc and 5 amps.

I attempted to build one from schematics for a +/- 15 vdc power supply and it didn't work out.

I have a decent transformer. 17-0-17 7.5 amps,
I have a 7818 and a 7918 regulator.
I have 2 TIP35C and 2 TIP36C.

I do not know how to calculate resistor and capacitor values. I do not know which capacitors to use.

I really need this mixer and help to make it work.

Thanks

 

[DUG]

Is this what you are thinking?

 

[DUG]

Or with dual current boost transistors.

 

[PRR]

> 17-0-17 7.5 amps

This is dubious for 5A DC. The conversion for Amps DC back to AC is 1.6-1.8. You need 8A or 9A of AC rating to get 5A DC.

You will get 24V raw DC, dropped to 18V. So 6V drop times 5A is 30 watts, a large heatsink, at least as large as used for a 60W amplifier channel.

DUG has done the value selection and I agree.

This is not short-proof. (That would be complicated.)

What many-many-many studio operators do is get two open-frame power industrial supplies and strap them. These are fully engineered to work well long-term despite abuse. Acopian and Lambda (now TDK) are long-time quality suppliers.