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Interesting power supply

Started by Unknown August 9, 2014
Seems to be just a full-bridge rectifier and capacitor voltage divider.  Just wondering how well it works:

http://www.ebay.com/itm/90pcs-220UF-63V-Low-impedance-power-amplifier-AC-DC-POWER-SUPPLY-BOARD-DIY-KIT-/370877884267?pt=US_Amplifier_Parts_Components&hash=item565a0b676b

How much current can you get out of it?  It says 25A rectifier, but not sure about output current.
Den l=F8rdag den 9. august 2014 17.39.02 UTC+2 skrev edward....@gmail.com:
> Seems to be just a full-bridge rectifier and capacitor voltage divider. =
Just wondering how well it works:
>=20 >=20 >=20 > http://www.ebay.com/itm/90pcs-220UF-63V-Low-impedance-power-amplifier-AC-=
DC-POWER-SUPPLY-BOARD-DIY-KIT-/370877884267?pt=3DUS_Amplifier_Parts_Compone= nts&hash=3Ditem565a0b676b
>=20 >=20 >=20 > How much current can you get out of it? It says 25A rectifier, but not s=
ure about output current. what's interesting about it? it is just a standard rectifier cap combo=20 they just went overboard with the number of parallel caps, audiopholery or= =20 maybe they just got them cheap=20 -Lasse
edward.ming.lee@gmail.com wrote in
news:94298d61-eba9-4606-8b73-0ebd9d2137c2@googlegroups.com: 

> Seems to be just a full-bridge rectifier and capacitor voltage > divider. Just wondering how well it works: > > http://www.ebay.com/itm/90pcs-220UF-63V-Low-impedance-power-amplifier-A > C-DC-POWER-SUPPLY-BOARD-DIY-KIT-/370877884267?pt=US_Amplifier_Parts_Com > ponents&hash=item565a0b676b > > How much current can you get out of it? It says 25A rectifier, but > not sure about output current. >
It also says "input voltage:AC 12V". Its not a PSU, its just a bridge rectifier + bulk capacitor filter to be used with a big transformer. 12 to 15A would probably be OK -- Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED) ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk [at]=@, [dash]=- & [dot]=. *Warning* HTML & >32K emails --> NUL
> > Seems to be just a full-bridge rectifier and capacitor voltage > > divider. Just wondering how well it works: > > > http://www.ebay.com/itm/90pcs-220UF-63V-Low-impedance-power-amplifier-A > > C-DC-POWER-SUPPLY-BOARD-DIY-KIT-/370877884267?pt=US_Amplifier_Parts_Com > > ponents&hash=item565a0b676b > > > How much current can you get out of it? It says 25A rectifier, but > > not sure about output current. > > It also says "input voltage:AC 12V".
It's probably a typo. I think they mean AC -> 12V.
> Its not a PSU, its just a bridge > rectifier + bulk capacitor filter to be used with a big transformer.
No transformer. In the connection picture, they wire it direct to the power amp. There is a small transformer on the right, but it's probably a separate circuit.
> 12A to 15A would probably be OK
On Sat, 9 Aug 2014 08:39:02 -0700 (PDT), edward.ming.lee@gmail.com wrote:

>Seems to be just a full-bridge rectifier and capacitor voltage divider. Just wondering how well it works: > >http://www.ebay.com/itm/90pcs-220UF-63V-Low-impedance-power-amplifier-AC-DC-POWER-SUPPLY-BOARD-DIY-KIT-/370877884267?pt=US_Amplifier_Parts_Components&hash=item565a0b676b > >How much current can you get out of it? It says 25A rectifier, but not sure about output current.
Idiotic. Those long skinny PCB traces will dominate the output impedance. Are the caps 220u or 330u? Some audiophool will like the way it sounds, I guess. Is that a fake tube in the pic halfway down? -- John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at highlandtechnology dot com Precision electronic instrumentation
On a sunny day (Sat, 9 Aug 2014 08:39:02 -0700 (PDT)) it happened
edward.ming.lee@gmail.com wrote in
<94298d61-eba9-4606-8b73-0ebd9d2137c2@googlegroups.com>:

>Seems to be just a full-bridge rectifier and capacitor voltage divider. Just wondering how well it works: > >http://www.ebay.com/itm/90pcs-220UF-63V-Low-impedance-power-amplifier-AC-DC-POWER-SUPPLY-BOARD-DIY-KIT-/370877884267?pt=US_Amplif >ier_Parts_Components&hash=item565a0b676b > >How much current can you get out of it? It says 25A rectifier, but not sure about output current.
It would be better to use real capacitors with screw terminals: http://www.ebay.com/itm/141084938689 ebay has many more real capacitors Any bridge will do if it meets the current, but beware of the peak charge current. Anyway I see a 'tube' in that picture so somebody perhaps tries to sell 'HIGHER FIDILITY", and sub 10 Hz audio. In that case if that is your thing better use gold cables too. For an audio amp it makes NO SENSE whatsoever, as the feedback loop will get rid of the ripple that is already minimal in a symetrical design. Take botton ripple om max power and that is your peak to peak output voltage minus teh chisp intermnal drops, not clear what chips they use, look up spec. C is recharged every 10 mSs in Europe, Q = C.U = i.t 25 A and 20,000 uF and 10 mS ??? U = (i.t) / C U = 25 * .01 / (20*10^-3) = 12.5 V ripple 12.5V ripple on 63 V or is it 2 x 31.5 V... (just a wild ballpark) mm, seems something is wrong! You need a bigger C :-) or have less power available! And I do not think those chips in that picture actually draw 25A ... Mine works great with 80 W: http://panteltje.com/panteltje/amplifier/index.html My caps are smaller! So do not waste your money. math OK? Mine works! No tubes.
> >Seems to be just a full-bridge rectifier and capacitor voltage divider. Just wondering how well it works: > > >http://www.ebay.com/itm/90pcs-220UF-63V-Low-impedance-power-amplifier-AC-DC-POWER-SUPPLY-BOARD-DIY-KIT-/370877884267?pt=US_Amplifier_Parts_Components&hash=item565a0b676b > > >How much current can you get out of it? It says 25A rectifier, but not sure about output current. > > Idiotic. Those long skinny PCB traces will dominate the output impedance.
I don't see the trace. But they are just connecting adjacent caps (probably all in series), it could be very wide traces.
> Are the caps 220u or 330u?
It says 220u and 220u x 90 = 20,000u.
Den l=F8rdag den 9. august 2014 18.13.38 UTC+2 skrev edward....@gmail.com:
> > > Seems to be just a full-bridge rectifier and capacitor voltage >=20 > > > divider. Just wondering how well it works:=20 >=20 > >=20 >=20 > > > http://www.ebay.com/itm/90pcs-220UF-63V-Low-impedance-power-amplifier=
-A
>=20 > > > C-DC-POWER-SUPPLY-BOARD-DIY-KIT-/370877884267?pt=3DUS_Amplifier_Parts=
_Com
>=20 > > > ponents&hash=3Ditem565a0b676b=20 >=20 > >=20 >=20 > > > How much current can you get out of it? It says 25A rectifier, but >=20 > > > not sure about output current.=20 >=20 > >=20 >=20 > > It also says "input voltage:AC 12V". >=20 >=20 >=20 > It's probably a typo. I think they mean AC -> 12V. >=20
12V AC in, +/- ~17V DC out
>=20 > > Its not a PSU, its just a bridge=20 >=20 > > rectifier + bulk capacitor filter to be used with a big transformer. =
=20
>=20 >=20 >=20 > No transformer. In the connection picture, they wire it direct to the po=
wer=20
> amp. There is a small transformer on the right, but it's probably a sepa=
rate
> circuit.
the transformer just isn't on the picture, you'll need one -Lase=20
Den l=F8rdag den 9. august 2014 18.27.37 UTC+2 skrev edward....@gmail.com:
> > >Seems to be just a full-bridge rectifier and capacitor voltage divider=
. Just wondering how well it works:
>=20 > >=20 >=20 > > >http://www.ebay.com/itm/90pcs-220UF-63V-Low-impedance-power-amplifier-=
AC-DC-POWER-SUPPLY-BOARD-DIY-KIT-/370877884267?pt=3DUS_Amplifier_Parts_Comp= onents&hash=3Ditem565a0b676b
>=20 > >=20 >=20 > > >How much current can you get out of it? It says 25A rectifier, but no=
t sure about output current.
>=20 > >=20 >=20 > > Idiotic. Those long skinny PCB traces will dominate the output impedanc=
e.=20
>=20 >=20 >=20 > I don't see the trace. But they are just connecting adjacent caps (probab=
ly all in series), it could be very wide traces.
>=20 >=20 >=20 > > Are the caps 220u or 330u? >=20 >=20 >=20 > It says 220u and 220u x 90 =3D 20,000u.
there's a clear picture of the board,=20 http://i.ebayimg.com/00/$%28KGrHqYOKjwE2JTPG%28pHBNn%29msnGfg~~_1.JPG it is just s standard bipolar supply, all caps in parallel half for + half = for - -Lasse
> it is just s standard bipolar supply, all caps in parallel half for + half for
OK, i misunderstood this board. But would it work if the caps are in series, as i originally expected? Let say drawing 2A to 3A from the center of a capacitor voltage divider, away from the line and neutral (which could be reversed sometime).