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Old 16th January 2008, 06:39 PM   #1021
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Quote:
Originally posted by jacco vermeulen
Junk Fuwed Book:

With 1000uf caps instead of 2200=> charge ripple without CRC still less than 100mV.
Use 1000uf and double the R21/R23/R24(a) value, 0.6W typies (Cheesecakes even go doublesided)

MUR1xx, just as fast.

The pumpkin has C8 C10 C13 C14 - rated for 220-470uF and the Shunty has C2 2a 15 15a 16 16a rated for 1000 - 2200uF.

So assuming the same grade and series of electrolytic caps - what is the advantage or disadvantage of using a bigger vs smaller cap? Bigger cap = less ripple?

Still a noob

her shann
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Old 16th January 2008, 07:07 PM   #1022
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Rough formula:

Vripple = [ 1700 x Current(max) ] / uF number.

A smaller same brand/type cap is cheaper and has a higher ESR number.
By increasing the resistor value the number R*C remains constant, same corner frequency, same noise reduction before entering the 1st. reg. stage.
Does mean the voltage drop across the series resistors is higher, picking a transformer with 1 Vac higher secondaries straightens it out.

(btw: USA guys looking for fancy food spindle ptfe caps should type in : Voltronics A1 series, the big vendors likely have them for at least $25 the pop)
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Old 16th January 2008, 07:28 PM   #1023
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Quote:
Originally posted by jacco vermeulen
............
(btw: USA guys looking for fancy food spindle ptfe caps should type in : Voltronics A1 series, the big vendors likely have them for at least $25 the pop)

ya nutz
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Old 16th January 2008, 07:31 PM   #1024
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True, but it's just a suggestion for MarC to dive another dumpster.
The last one must have smelled funny, probably had a FED NARC sticker.
=>http://www.diyaudio.com/forums/showt...63#post1394363
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Old 16th January 2008, 07:34 PM   #1025
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Originally posted by Manu
Holger : watt is that on the gigantisch pic you've posted?

Manu

(BTW : sehr schön gelungen das Bild)
Danke.
http://www.wavac-audio.jp/he833_e.html
Had a pair of those for a review about two years ago.
Veeery ugly
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Old 16th January 2008, 07:42 PM   #1026
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U G L Y, I know ...

Both Shunty tested - working OK.
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Old 16th January 2008, 07:44 PM   #1027
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Old 16th January 2008, 07:49 PM   #1028
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Originally posted by spavleski



you forgot to say that you have few smoked resistors ( my last add in Cook......) and that you also have CM choke in it .......
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Old 16th January 2008, 07:50 PM   #1029
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Originally posted by spavleski
U G L Y, I know ...

Both Shunty tested - working OK.

Nice going! How did you get away with not running a heatsink, or is that coming?
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Old 16th January 2008, 07:51 PM   #1030
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Thanks
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