Quick note on using USB power supplies on nanoPEB/CF7+

[+OLD CS1]

I was having horrendous problems with noise in my program cassette recordings and I accidentally found it was because the USB power supply I was using on my nanoPEB was causing the noise. I have not tested it but I suspect the USB output is not fully isolated from the live power.

 

At VCF I found the system with the nanoPEB and an F18A had noise in the video output. Different USB power supply, which I had used in the past without problem, was injecting noise. Now, in this case I believe the problem was due to the USB power supply being on the battery side of the UPS while the computer was on the surge-only side. That thought is hind-sight but the immediate solution at the time was to replace the USB power supply with a proper 5V PSU.

 

That said, a little 2200mAh battery pack runs everything just fine, and the low power draw means I can run the system for several hours. Oh, and those ratings on the battery packs are hardly ever correct -- these little WalMart specials I picked up for $2 each and while they will take 2200mAh they output about 1300mAh.

[+FarmerPotato]

I was having horrendous problems with noise in my program cassette recordings and I accidentally found it was because the USB power supply I was using on my nanoPEB was causing the noise. I have not tested it but I suspect the USB output is not fully isolated from the live power.

 

At VCF I found the system with the nanoPEB and an F18A had noise in the video output. Different USB power supply, which I had used in the past without problem, was injecting noise. Now, in this case I believe the problem was due to the USB power supply being on the battery side of the UPS while the computer was on the surge-only side. That thought is hind-sight but the immediate solution at the time was to replace the USB power supply with a proper 5V PSU.

 

That said, a little 2200mAh battery pack runs everything just fine, and the low power draw means I can run the system for several hours. Oh, and those ratings on the battery packs are hardly ever correct -- these little WalMart specials I picked up for $2 each and while they will take 2200mAh they output about 1300mAh.

 

I used my 5V1A laboratory bench supply for the nanoPEB. I see the nanoPEB drawing no more than 75 mA while actively loading files and running a game.

After 3-4 hours that would total about 1300mAh. Is that consistent with your battery life?