[bubbaj]

I finally got around to getting a wall wart for my Meta42. The Meta42 is normally powered by 2 9V batteries. I picked up a 24VDC 400mA supply. When I power it up I get a strong hum. No source required. Anything I can do about this? Is a better power supply needed?
Thanks
bj

 

[Dreamslacker]

What kind of power supply are you using?

Linear?
Switching?
Linear regulated?
Switching regulated?

 

[bubbaj]

It's a black one!

I really don't know. Here's what it says on the unit:

SR Components
AC Adaptor
Class 2 Transformer
Item No: DC-24-400-3.5
Model NO: DDU240040

Input: 120VAC 60Hz 14.5 W
Output: 24VDC 400mA

That probably doesn't answer your question but that's all I know.
bj