for my amp i building out of Randy Sloan's book.
In fact any info on a complete power supply would be cool. Transformer, rectifier, smoothing caps, ect.
In fact any info on a complete power supply would be cool. Transformer, rectifier, smoothing caps, ect.
Have a look at:
http://www.coldamp.com/opencms/opencms/coldamp/en/productos/sps80/index.html?
I think that they can also provide custom voltage versions from +/-40 to the standard voltage, +/-60V if I don't remember wrong.
http://www.coldamp.com/opencms/opencms/coldamp/en/productos/sps80/index.html?
I think that they can also provide custom voltage versions from +/-40 to the standard voltage, +/-60V if I don't remember wrong.
Sounds like a standard Transformer/bridge/caps PS will do - I assume that you don't need a regulated supply from the way you phrased your request.
You're looking at at least a 400 VA transformer (42V x 5A x 2), with 30-0-30 or dual 30VAC secondaries. This will give you 30 VAC x 1.4 = 42VDC nominal (minus diode drops). It will be a bit higher at idle, a bit lower under load.
A standard metal case bridge rectifier should do. Go for at least 25A rating. If you go nuts with filter capacitance, bump this up to 35A or more. Anything over 100V will work. You can use fast/soft recovery diodes if you prefer. A 100 nF cap across the AC terminals might help.
A rule of thumb for class AB amps is use 10,000 uF for every 100 watts of output in the main filter. Some use more, some less. You could do this and call it a day. Some add a smaller value electrolytic and even smaller film cap (100 uf and 1 uf for example if you use 10,000 uf) to bypass the main caps. Others add an R-C snubber. The snubber values depend on your transformer and main capacitors.
It's not hard to make a filtered PS. be wary of mains voltage and bring it up slowly with a Variac or use a light bulb in series with the mains connection the first time you power it up.
Monitor the output voltages from a safe distance - no voltage on one rail probably means you have a cap wired backwards. Shut down and fix it. Left connected the wrong way long enough the cap will burst/explode and cover your bench with foul smelling electrolyte.
Don't forget a mains fuse. You might need a slow blow fuse if your transformer is big.
You're looking at at least a 400 VA transformer (42V x 5A x 2), with 30-0-30 or dual 30VAC secondaries. This will give you 30 VAC x 1.4 = 42VDC nominal (minus diode drops). It will be a bit higher at idle, a bit lower under load.
A standard metal case bridge rectifier should do. Go for at least 25A rating. If you go nuts with filter capacitance, bump this up to 35A or more. Anything over 100V will work. You can use fast/soft recovery diodes if you prefer. A 100 nF cap across the AC terminals might help.
A rule of thumb for class AB amps is use 10,000 uF for every 100 watts of output in the main filter. Some use more, some less. You could do this and call it a day. Some add a smaller value electrolytic and even smaller film cap (100 uf and 1 uf for example if you use 10,000 uf) to bypass the main caps. Others add an R-C snubber. The snubber values depend on your transformer and main capacitors.
It's not hard to make a filtered PS. be wary of mains voltage and bring it up slowly with a Variac or use a light bulb in series with the mains connection the first time you power it up.
Monitor the output voltages from a safe distance - no voltage on one rail probably means you have a cap wired backwards. Shut down and fix it. Left connected the wrong way long enough the cap will burst/explode and cover your bench with foul smelling electrolyte.
Don't forget a mains fuse. You might need a slow blow fuse if your transformer is big.
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