I have a project that I want to set up in a situation where it will run all day, for at least two days in a row. It's got a Picaxe 08M and one of the Tenda MP3 boards, powered from the Picaxe. I don't think that AA batteries will make it all the way through, and I don't want to get a frantic phone call telling me that the project is down and that I need to get back and change the batteries!
So I'm looking at regulated power supplies. Jameco (near me) has several that look good, such as this one:
https://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10001&langId=-1&catalogId=10001&pa=1940660&productId=1940660
But a quick look at Manual 1 tells me that I should use a 9V supply and build a small circuit to regulate it down (see page 26). Why is this? Shouldn't I just get the 5V supply and be done with it?
So I'm looking at regulated power supplies. Jameco (near me) has several that look good, such as this one:
https://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10001&langId=-1&catalogId=10001&pa=1940660&productId=1940660
But a quick look at Manual 1 tells me that I should use a 9V supply and build a small circuit to regulate it down (see page 26). Why is this? Shouldn't I just get the 5V supply and be done with it?