[sdiy] power woes

[Barry Klein]

Also, a Dunlop supply, different model, is available cheaper from 
Sweetwater:
http://www.sweetwater.com/store/detail/ECB003/

I've never heard of Dunlop supplies before...

Your problem may be that the DC load is actually too small.  The supply may 
need
a minimum load to regulate well - otherwise is may go into a lower switching 
rate
power save mode with lousy specs for your application.  Just for kicks try 
placing
a resistive load at your circuit input to see if this is what is happening.

Barry

----- Original Message ----- 
From: "dan snazelle" <subjectivity at hotmail.com>
To: "synth diy" <synth-diy at dropmix.xs4all.nl>
Sent: Saturday, March 06, 2010 7:15 AM
Subject: [sdiy] power woes


> Ok
>
> I am sitting here with a pile of DC adapters. (trying to find one to 
> bundle with my products)
>
> half of them cause HUM, half of them cause a whine (switching)
>
> Only 2 out of the pile don't cause ANY noise
>
>
> One is a DUNLOP class 2, 60hz 7w, 9vdc 200ma adapter which is made in 
> china and has a chinese model number of
>
> ad-0920
>
>
> i can find these online for $12-15 dollars a piece
>
>
>
> the other is one of the new BOSS switching adapters.
>
> (it costs 30 bucks!)
>
>
> one of the odd things is that some of the switching adapters or class 2 
> adapters have
> seemingly the same SPECS but cause different problems or noise
>
>
> SO...my question is whether anyone has any advice on DC adapters
>
>
> i might be able to get a bunch from dunlop but it still doesnt answer WHY 
> some cause noise and some dont
>
>
> thanks so much!
>
>
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at dropmix.xs4all.nl
> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>