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Groups > sci.physics > #530371
| From | benj <nobody@gmail.com> |
|---|---|
| Newsgroups | sci.physics |
| Subject | Re: Capacitor Question |
| References | (2 earlier) <pan.2015.11.03.23.06.12@localhost.localdomain> <p2sngc-esb.ln1@mail.specsol.com> <pan.2015.11.04.02.49.26@localhost.localdomain> <Xhi_x.106405$962.6918@fx09.iad> <pan.2015.11.04.07.31.01@localhost.localdomain> |
| Message-ID | <tFs_x.4$FR4.2@fx17.iad> (permalink) |
| Organization | TeraNews.com |
| Date | 2015-11-04 14:04 -0500 |
On 11/04/2015 02:30 AM, Fabian Russell wrote:
> On Wed, 04 Nov 2015 02:17:11 -0500, benj wrote:
>
>>
>> These are pretty large and expensive units!
>> I presume you are drawing some serious current here.
>>
>
> Expensive? No way. DigiKey has 'em for $2.75 a pop.
4700 microfarad at 50 volts? I'm looking at "screw terminal"
electrolytics at Mouser and they are nice but $89 each!
> Serious current? Not really. 3 amp regulators are no problem.
> I do a lot of audio work and the low voltages involved can often
> require a lot of current.
With a regulator all you need is enough C to keep ripple low enough that
the regulators can clean it up at full current. Though more capacitance
is always better! Most of my amps use pretty small filter caps (that I
would consider too small, but hey) and they look pretty cheap too. Seem
to work fine though it's not "high end" gear.
> I built a power supply for a 50 Watt audio amp. I think
> I got 10 amp regulators in there. (I'll have to open it up
> for a look). The big problem was finding transformers able
> to give a high enough current output.
I've got a few 50 watt amps and the filters in there are pretty small as
I recall. Certainly not the big blue screw terminal monsters.
> But my supplies are general purpose and I can use them to power
> low current circuits as well. It's good to have headroom even
> if not always needed.
>> I'd suggest going with a modern switching supply instead.
>>
>
> There are two reasons for not using a switching supply.
>
> 1) They always have to have a load attached or else poof.
> 2) They are far more complicated in design and why burden
> oneself unnecessarily?
1. Proper design and modern semiconductors takes care of that.
2. Because of the very problems you are encountering having to filter
line frequencies. Size, weight, cost, life, etc. Just consider the power
supply in your computer! Can put out massive current yet is light, small
reliable and almost free! Filtering high frequencies takes far less
capacitor than low.
Today Class D Amps are the shiznit!
--
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/:/\:\ \ /:/\:\ \ /:|:| | ___ /::\__\
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/:/\:\ \:|__| /:/\:\ \:\__\ /:/ |:| /\__\ \:\/:/ /
\:\~\:\/:/ / \:\~\:\ \/__/ \/__|:|/:/ / \::/ /
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\:\/:/ / \:\ \/__/ |::/ /
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Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-03 22:14 +0000
Re: Capacitor Question gilber34 <fafa@invalid.com> - 2015-11-03 16:35 -0600
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-03 22:59 +0000
Re: Capacitor Question gilber34 <fafa@invalid.com> - 2015-11-03 18:10 -0600
Re: Capacitor Question jimp@specsol.spam.sux.com - 2015-11-03 22:47 +0000
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-03 23:07 +0000
Re: Capacitor Question jimp@specsol.spam.sux.com - 2015-11-03 23:20 +0000
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-03 23:42 +0000
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-04 02:49 +0000
Re: Capacitor Question gilber34 <fafa@invalid.com> - 2015-11-03 21:40 -0600
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-04 04:01 +0000
Re: Capacitor Question jimp@specsol.spam.sux.com - 2015-11-04 06:03 +0000
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-04 07:07 +0000
Re: Capacitor Question jimp@specsol.spam.sux.com - 2015-11-04 20:29 +0000
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-04 20:51 +0000
Re: Capacitor Question jimp@specsol.spam.sux.com - 2015-11-04 21:08 +0000
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-04 21:53 +0000
Re: Capacitor Question jimp@specsol.spam.sux.com - 2015-11-04 22:20 +0000
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-04 22:42 +0000
Re: Capacitor Question jimp@specsol.spam.sux.com - 2015-11-04 23:07 +0000
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-05 00:28 +0000
Re: Capacitor Question jimp@specsol.spam.sux.com - 2015-11-05 00:46 +0000
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-05 00:39 +0000
Re: Capacitor Question jimp@specsol.spam.sux.com - 2015-11-05 00:58 +0000
Re: Capacitor Question benj <none@gmail.com> - 2015-11-04 18:25 -0500
Re: Capacitor Question benj <none@gmail.com> - 2015-11-04 18:37 -0500
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-05 00:09 +0000
Re: Capacitor Question benj <nobody@gmail.com> - 2015-11-04 21:35 -0500
Re: Capacitor Question gilber34 <fafa@invalid.com> - 2015-11-04 21:51 -0600
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-05 04:19 +0000
Re: Capacitor Question gilber34 <fafa@invalid.com> - 2015-11-05 11:10 -0600
Re: Capacitor Question "reber g=emc^2" <herbertglazier0@gmail.com> - 2015-11-05 09:15 -0800
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-05 18:08 +0000
Re: Capacitor Question jimp@specsol.spam.sux.com - 2015-11-05 19:26 +0000
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-05 19:44 +0000
Re: Capacitor Question jimp@specsol.spam.sux.com - 2015-11-05 19:56 +0000
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-05 20:53 +0000
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-05 21:52 +0000
Re: Capacitor Question benj <none@gmail.com> - 2015-11-04 18:41 -0500
Re: Capacitor Question gilber34 <fafa@invalid.com> - 2015-11-04 21:54 -0600
Re: Capacitor Question benj <nobody@gmail.com> - 2015-11-04 02:17 -0500
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-04 07:30 +0000
Re: Capacitor Question gilber34 <fafa@invalid.com> - 2015-11-04 07:48 -0600
Re: Capacitor Question benj <nobody@gmail.com> - 2015-11-04 14:04 -0500
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-04 19:28 +0000
Re: Capacitor Question benj <none@gmail.com> - 2015-11-04 18:49 -0500
Re: Capacitor Question gilber34 <fafa@invalid.com> - 2015-11-04 20:41 -0600
Re: Capacitor Question Fabian Russell <root@localhost.localdomain> - 2015-11-05 03:16 +0000
Re: Capacitor Question gilber34 <fafa@invalid.com> - 2015-11-04 21:58 -0600
Re: Capacitor Question "reber g=emc^2" <herbertglazier0@gmail.com> - 2015-11-04 12:14 -0800
Re: Capacitor Question benj <none@gmail.com> - 2015-11-04 18:44 -0500
Re: Capacitor Question gilber34 <fafa@invalid.com> - 2015-11-04 20:41 -0600
Re: Capacitor Question gyansorova@gmail.com - 2015-11-05 16:34 -0800
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