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Hi,Being obseesed with R load parafeed at the moment, I'm trying to do it quickly with 300B. If above thing can work fine, I can use off the shelf power tranny from local source. It seems to be able to work, but I hope to hear from the knowledged.
Also is it possible to use input choke (between the rectifier and capacitor) with voltage doubler?Thanks!
Follow Ups:
ALL you are right word I think.
It's funny that I realized that what I did was just normal (+) (-) supply used for OP amp supply like Steve O said, like there's nothing new under the sun. Obsession and lack of knowledge drew a funny question from me like this.I feel comfortable now except the current rating of the transformer.
CY,
I guess it depends upon your definitions.Most commonly you see a circuit without the bottom cap and without the 2 left had side capacitors. Then the cap is charged via 1 diode from one half of the secondary on 1 half cycle and via the other diode and other half secondary on the other half cycle.
With that arrangement and (for example) a 240-0-240 secondary you would get about 300V DC.
With your circuit as shown and the same (for example) transformer what happens is that one cap is charged from 1/2 secondary and the other is simultaneouly being charged from the other half seconday on 1 half cycle and they simply swap over for the other half cycle. Therefore you would get 300V DC across each cap and 600V DC in total. So from that point of view, YES it is a voltage doubler.
One caution. Most 240-0-240 (again for example) transformers are rated with the assumption that the circuit will be as per the most common circuit referred to at the top and that you will be drawing current from only half of the centre tapped secondary at a time. With the circuit as you have drawn you will be drawing current from both secondary halves all the time and so you need a transformer with double the current rating - or comming at from the other direction you can only use the transformer up to half of its current rating.
the only difference between this and most circuits using a FW bridge is that the CT (which usually develops 1/2 the output voltage) is connected between the caps. I suppose this would eliminate the need to use balancing resistors on the caps, but other than that, it's nothing special.
...as seen in countless transistor amp designs.
Close, but no cigar. "El Cheapo" uses a "full wave" doubler in its B+ supply.Voltage multiplier circuits are STRICTLY cap. I/P. The place for the choke is after the doubler cap. stack. Think "extended" CLC (pi section) filter. Again, that's exactly what we did in "El Cheapo".
BTW, the rectifier winding has to be RMS rated for 4X the DC draw. You use LARGE value caps. in the doubler stack.
Eli D.
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