I have a 168 and 328 Stalker. I have been using the 168 Stalker with a 5vdc Arduino power supply connected to the JST connector without problems.
I tried using the same power supply with the 328 and it would not power up. I measured the voltages on the 5vdc pin and measured 3.143 volts. I then powered the 328 with the Uart_SB adapter and it worked fine and the 5vdc pin measured 4.97 volts. After reviewing the Stalker documentation, it indicates that the voltage for the JST should be 7-12 vdc which is higher than a standard Arduino power supply. I then tried powering the 328 with the JYE tech ocsilloscope 9VDC power supply and the Stalker operated properly then. Even with this power supply the 5vdc pin only measured 4.53 volts.
It appears that the onboard power controller does not regulate power very good and might be the reason some users have had problems with the SD card and Xbee. If other users are having any problems with their Stalker, they might want to check the voltage on the 5vdc pin to make sure there is enough power available.
It looks like it might be better to power the Stalker from the Uart port. Does anybody have recommendations for a safe power supply that can be used? The standard Arduino power supply puts out 5.21 vdc but I’m not sure it is safe to connect it directly to the Uart port.
Yes, Please supply a 7~12v power to the White JST connector.
we are sorry for the 5V Power regulate circuit is not comfortable on your board while supply 9V from the JST connector.
Please measure the 3.3v power.
No problem power the 5.21V(Arduino 5v) to the Uart Port.
And we are planning upgrade the Stalker now, Do you have many suggestions?
Please send email to me: albert.miao seeedstudio.com
Thanks
Just wanted to echo this problem. I’ve been trying to get a color LCD shield from sparkfun running on the Stalker but could not get the 3.3V required for operation. I was not even able to get 3 V on the pin when running from either a usb port, 9V battery, or a regulated power supply. Only by adding a secondary power supply did I get it to work. Power regulation seems to be a challenge. Any information that would fix this is appreciated.
I am using the DFRobot Keypad LCD shield on the Stalker but had to disconnect pin 10 because it interfered with the SD card write. I took a quick look at your shield and it looks like there might conflict with pins 11 and 13. You might want to look at the following thread that covers the pin usage on the Stalker:
There are a number of threads about the Stalker on the general Tech forum that were placed there before the dedicated Stalker thread existed. Is it possible to have them moved to the Stalker forum?