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-   -   Aleph 5 power supply. (http://www.diyaudio.com/forums/pass-labs/6110-aleph-5-power-supply.html)

Tony D. 17th September 2002 10:43 PM

Aleph 5 power supply.
 
I am building and Aleph 5 and I am wanting to use the power supply as shown at http://web.vip.hr/pcb-design.vip/power-5.html and I want to only use the first capacitor section of this supply, the 4 X 47,000uf portion.

Besides a higher ripple is there any reason why I can not use this section only? Or is it worth the extra expense and complexity to build the complete power supply?

And while I am on this subject what about building the front section only but using the inductor as well?

Thanks for any comments.


Tony D.

Nelson Pass 17th September 2002 11:03 PM

It's worth it, although if you want to, you could consider
47KuF / 2 mH / 47KuF and it would be cheaper and still
work well, especially if it's only for one channel. Make sure
the ripple rating of the first cap is about 3 times the DC
current draw.

PedroPO 18th September 2002 01:16 AM

well Nelson, you must say that on your Aleph service manual U used only Caps, no coils, and if thats good for you I guess Its good for me ;)

I'm going to use only 2X47kuF/ch and a small 4uF polyester cap in paralell with each big capacitor to reduce the cap inductance as many of the guys do.

I don't know if it is ok, but I think I read something written by NP about this subject, don't know where :(

please correct me if I'm wrong before I kill the PSU, hehe

Tony D. 30th September 2002 06:42 PM

Just a follow up question regarding this power supply, on the weekend I bought a pair of Solen 3.9uf inductors in 16 guage.

Would there be any reason why these would not substitute for the 2uf inductors that Nelson has suggested?

I bought the 3.9's for $2. each and would like to use them if possible as the cost effectiveness is there.


Thanks for any info.



Tony D.

Peter Daniel 30th September 2002 06:52 PM

What's the resistance of the inductors?

Tony D. 30th September 2002 07:20 PM

Hi Peter,

Per the Solen site the DCR of the inductor is .73R.


Tony D.

Peter Daniel 30th September 2002 07:25 PM

I think it is still OK, but as I remember some people complained about coils getting hot because of higher resistance.

Jason Hubbard 30th September 2002 07:29 PM

Capacitor Ripple Current
 
Nelson states that you should have a riplle current rating of 3 times the current draw.

I have some computer grade reservoir capacitors of 58,000uf, but i don't know the ripple current rating and have no manufacturers data.

Is there any way of measuring and/or calculating the ripple curent if it is not known?

Nelson Pass 30th September 2002 07:33 PM

Not that I know of. Just try them out, and if they
blow up, you probably have exceeded it.

:bigeyes:

hifi 30th September 2002 07:49 PM

aaah....the crash and burn method =) very effective... I guess you could check if the caps are hot to the touch or atleast "un naturaly warm" when in use that would most likely be a warning sign..

btw...i must question those supplyes why do one chose to put the larger capacitance before the inductor? and a smaler one after? ... to me it would be better to do the otherway around.. a bit lower current draw on start up a larger energy reservoar availibly to the amp (not isolated by inductor dcr) the inductor sees more ripple so it gets more work done...

why place the larger capacitance first??

/micke


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