AC PSU for cmoy

[TerTop 0]

Hi been lurking quite sometime now . I noticed some ppl built an ac powered source for the headamp. May i asked where can i find a tutorial for this ac power source? Also does anyone measured what is the nominal ripple reading of this PSU? Actually planning to built a cmoy with OPA627 with 15Vp-p. Any idea?

Edited April 13, 2004 by TerTop

[tropicalrips 0]

this is the PSU that i built for my Cmoy

its also powering a cmoy using opa627 with Buf634 as buffers

i don't know what is the nominal ripple on the setup how do i measure this anyway

i hav a 12-0-12v transformer, the design is from a DIY kit for a dual regulated PSU that i bought i think Tangents site has a tutorial for something similar

[jtfoo 0]

Want to measure ripple, best is to borrow Jason's oscilloscope and visually see the ripples in wave.

 

If you're poor like me, but still own a DMM that is precise, then set it to measure AC voltage. Can still measure some mV of ripple.

[tropicalrips 0]

jason is your scope gethering dust

[Firefox 0]

Hi been lurking quite sometime now . I noticed some ppl built an ac powered source for the headamp. May i asked where can i find a tutorial for this ac power source? Also does anyone measured what is the nominal ripple reading of this PSU? Actually planning to built a cmoy with OPA627 with 15Vp-p. Any idea?

Most power supplies built based on the LM317/337 or LM78XX/79XX regulators are good enough for amplifiers. You'd not hear any humming unless the power supply is not well built or unless you have a ground loop in the system.

[hacknet 0]

if you want to measure ripple, put a large value cap in series with your ac meter and measure the supply. the dc cap would filter out the DC leaving the variation in the supply. the reading you get would be the RMS of the ripple. i`ve got a scope and it really doesn`t help much other than tell you that there is ripple

[TerTop 0]

Hi been lurking quite sometime now . I noticed some ppl built an ac powered source for the headamp. May i asked where can i find a tutorial for this ac power source? Also does anyone measured what is the nominal ripple reading of this PSU? Actually planning to built a cmoy with OPA627 with 15Vp-p. Any idea?

Most power supplies built based on the LM317/337 or LM78XX/79XX regulators are good enough for amplifiers. You'd not hear any humming unless the power supply is not well built or unless you have a ground loop in the system.

Ah.. thanks for the assurance. I managed to a linear regulated wallwart 24VDC with <100mV ripple rating for RM124.

http://www.rsmalaysia.com/cgi-bin/bv/searc...chText=400-6939

 

Do you guys think this is good enough? Or the diy would perform better? May i know roughly what is the cost of complete set DIY with the LMxxx chip mentioned above? Thanks.

[jtfoo 0]

if you want to measure ripple, put a large value cap in series with your ac meter and measure the supply. the dc cap would filter out the DC leaving the variation in the supply. the reading you get would be the RMS of the ripple. i`ve got a scope and it really doesn`t help much other than tell you that there is ripple

Your scope not useful ar... Then sell to me cheap cheap.. I'm a poor diyer and my most expensive tool is my DMM which does not cost more than $100..

Edited April 15, 2004 by jtfoo

[jasonhanjk 0]

Normal 317 config is about 40mV ripple.

[TerTop 0]

Normal 317 config is about 40mV ripple.

Great info Jason! Between the two LMxxx chips, which one is more recommended specifically?

[jasonhanjk 0]

317 和 337.

[dreamie 0]

317 和 337.

Forgot to switch language mode after flaming at sgchinese?

[TerTop 0]

After searching for a while, Im thinking about the Jan Meier PSU design. But it is fixed at 30Vpp. Any idea how to change it to be variable between 12Vpp and 30Vpp?

 

Link over here. http://headwize2.powerpill.org/projects/sh...=meier3_prj.htm

Edited April 16, 2004 by TerTop

[jasonhanjk 0]

317 和 337.

Forgot to switch language mode after flaming at sgchinese?

No. I am flaming back those singapore gina who are attacking at that web.

[jasonhanjk 0]

LM337 and 337 can bo cofigure to be variable.