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By MDMac
#114212
I've been trying to get this sparkfun project (http://tinkerlog.com/2009/05/15/interfa ... lit-gm862/) to work successfully but haven't had any luck. I've included an image of my circuit (please excuse the messy wiring): http://yfrog.com/mvphotonov2444646pmj

I've tried using various cell phone batteries to no avail. The console will show that the module turns on, the led blinks only once, but when it tries to initialize the the modem I always get "no response". The transistor is not a bc337 but a MPS2222A from radio shack. Also, the capacitor is a 100uF tantalum capacitor from digikey http://search.digikey.com/scripts/DkSea ... ND&x=0&y=0.

The picture shows me powering the module using the arduino mega's 5v output, but I've tried the power supply at my uni's lab and various cell phone batteries (up to 1500mAh, but not exactly 2000mAh). Not sure if this is a problem with the peak amperage of 2A (which seems a little much) or a wiring problem. Any thoughts?