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Unread 05-01-2011, 22:28
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Re: noisy Power Distribution boards

Quote:
Originally Posted by Alan Anderson View Post
If you're just running a programming testbed, with no significant high-current loads, the "high" voltage of a fully-charged battery is going to be an issue. A 12 volt power supply capable of a few amps might work better. (Unless you really know what you're doing, use a linear supply and not a switching one.)
Interesting you should say that.
Usually when I get that noise loudly, it means my battery is low (I think it starts at 12v, but it may start a little higher.)

I have in fact used a switching power supply. (14v, 9A max continuous) If I have the Robot Radio plugged in when I start the robot up, it hangs around 3v. If I disconnect power to the robot radio, the power supply jumps up to 14v, and I can plug the robot radio in again with no problems.

As a general rule, the more switcher power supplies you have, the noisier it will become. I can sometimes reduce the noise by disconnecting the analog breakout and digital sidecar. (Except for my Black Jaguars, my hardware is 2009, so the Analog Breakout does not have a linear regulator).
Wouldn't it be nice to be able to disconnect power to the camera and robot radio power supplies when you didn't need them? I would think a 1A ATC fuse and holder would do that wonderfully.

I also get interesting results with the 14v switcher power supply when I have 9 Jaguars attached; several of them have a delayed startup from brownout.
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