Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: mantale1 on January 17, 2011, 06:23:27 PM

Title: $50 bot, 4 AA radioshack battery pack
Post by: mantale1 on January 17, 2011, 06:23:27 PM
I'm using the radioshack battery pack for the $50 bot. It's unclear from the tutorial and the $50 bot pdf whether I should solder the batter pack to the 3 male pins directly wired to the 5V regulator or if I should bypass that as the pdf doc says. What should I do?
Title: Re: $50 bot, 4 AA radioshack battery pack
Post by: Soeren on January 17, 2011, 10:17:36 PM
Hi,

I'm using the radioshack battery pack for the $50 bot. It's unclear from the tutorial and the $50 bot pdf whether I should solder the batter pack to the 3 male pins directly wired to the 5V regulator or if I should bypass that as the pdf doc says. What should I do?
Where in the .pdf do you see any mention of bypassing the regulator?

The power for the servos and the power for the rest are two different supplies. You may have luck running the servo supply to the voltage regulator input and thus avoid the 9V battery, but don't bypass it (or you'll kill your ┬Ácontroller).
What isn't clear from the .pdf is, that you need to connect the grounds of both supplies.
Title: Re: $50 bot, 4 AA radioshack battery pack
Post by: mantale1 on January 18, 2011, 01:29:28 PM
Well the reason I was confused was because in the tutorial the situation was described as one could either use a 4AA battery pack or a 9V battery. I was concerned because I did not want to bypass the voltage regulator, but the pdf doc suggests the the 4AA battery pack at 6V does not need to be wired to the regulator.
Title: Re: $50 bot, 4 AA radioshack battery pack
Post by: Soeren on January 18, 2011, 05:16:04 PM
Hi,

[...] but the pdf doc suggests the the 4AA battery pack at 6V does not need to be wired to the regulator.
Exactly - the positive wire from the 4xAA only goes to the servos, for which a 9V (PP3) wouldn't be able to supply the current needed.
Title: Re: $50 bot, 4 AA radioshack battery pack
Post by: VegaObscura on January 18, 2011, 09:04:37 PM
The tutorial at no point says you can use a 4AA Battery pack OR a 9V battery.  You can use either a 6V battery pack or both a 4AA battery pack and a 9v Battery.  Remember, you always need at least 6V to power the board, and a 4AA battery pack (assuming NIMH rechargable batteries) will only give you 4.8V.

Again, 6V OR 9V+4AA
Title: Re: $50 bot, 4 AA radioshack battery pack
Post by: mantale1 on January 18, 2011, 10:54:16 PM
Sorry about the confusion, I'm using the AA batteries X 4, not the NiMh rechargeable pack. So I have 6V. Thanks
Title: Re: $50 bot, 4 AA radioshack battery pack
Post by: Soeren on January 20, 2011, 11:34:25 AM
Hi,

I'm using the AA batteries X 4, not the NiMh rechargeable pack. So I have 6V.
Just a FYI...
4 primary cells (eg. alkaline) will start out at 6V, but before considered flat, the voltage have gone down to 3.6V - you won't be able to use more than say 25% of their capacity or less, as the voltage regulator needs at least 5.5V in to work.