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jonnyGURU
10-18-2006, 07:18 PM
Well... someone in another forum just ASSUMED I didn't know how to scope for ripple.

Apparently it was their way of justifying getting an OCZ despite > 120mV ripple. lol

So for the record, I'm going to post this here for future reference!

Here's the load tester:

http://www.sunmoontec.com/cpzs.asp?MidCode=SM-8800多功能電源測試儀

ATX12V specifies that ripple and noise are measured at the connectors with a 0.1uF ceramic capacitor and a 10uF electrolytic capacitor to simulate a system load.

These caps are installed behind the panel of the SunMoon tester, soldered to the inside of the BNC the scope leads screw onto. The old SM-268 had only one BNC output and one pair of caps. In fact, I had to re-solder those caps back into place after replacing the BNC after the BNC cable got caught on the edge of the desk. What a bitch that was! Ever see a 0.1uF ceramic cap?!?!

A selector knob switches what rail goes past these caps and out the BNC for the scope. So if I turn the knob to 12V1, etc.

The new 8800 has two BNC's, two sets of caps and the selector knob selects what TWO rails output via the BNC to the scope.

That'll be all. :D

jonnyGURU
10-18-2006, 07:36 PM
Photo of back side of BNC...

(Sorry it's a crappy cell phone picture.)

Super Nade
10-18-2006, 07:40 PM
Also, I believe such a combination (i.e Ceramic/Lytic or Tantalum/Lytic) is used to damp resonance to to the BNC's RF pickup/60 Hz noise. If that is his/their argument, why is the ripple on other units much lower than the OCZ? Why is the same levels replicated on all FSP units?

brandon
11-28-2008, 02:53 PM
When using a USB Instruments Stingray (or any other oscilloscope), is a differential probe required to test for ripple?

Oklahoma Wolf
11-28-2008, 03:51 PM
Yep, unless you're plugging straight into a SunMoon BNC.

Holy old thread bump, Batman! :D