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Power!!!

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i don't think that you understand, the output from the transformer has a high frequency oscolation combined with the sine wave. my power supply is going to be home made. i did an expiriment and learned that a voltage regulator with a current limiting resistor, connected to the base of a 3055 transistor, you get the same voltage out. all i need is to know the PNP equivalent of the 3055, i need a reliable function generator circuit (prefeerably somethin simple).
 
I can't see the high freq. oscillation. Anyways if you are seeing it that's because of the 4700 uF electrolytic caps internal inductance. Use some 100nF bypass capacitors.
 
ok i'll try that. i was kind of currios as to why so many poer supplies had those. my solution, (which made the problem worse) was to add a resistor to connect the caps to ground. Still no idea on what the PNP version of the 3055 is? i'm having trouble finding it on my own.
 
4700μF/ampere is the recommended value for the circuits posted further down the page in your posted link. 18 amps is going to involve some mighty large caps or a whole group of smaller ones bundled together! Looks like a fan is necessary to keep the heat generating components on the cool, calm side. None of those circuits are that great. There's no short circuit protection other than a fuse after the bridge rectifier itself. The transistors could very well go bust if current/heat climbs beyond limits. Search some more on Google using proper wording and you'll see many links to high current variable output power supplies.
 
the fan has been taken into account, and there is a circuit in place that will keep the fan operating properly, and by modifying the speed. the circuit that i posted was just a general circuit, on the more refined diagram, there is a fuse on each output. i am also working on a short circuit detector for the circuit using a LM2902 op-amp. it should detect the short on either rail. it is going to referenced the unregulated voltage instead of one of the regulated voltages.
 
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