[tracker2] T2 will not connect to computer

[pruittn2]

I have a T2 that will not connect to the computer.  I have verified that the 
null modem cable is good and pins 2 & 3 crossover from one end to the other.  I 
have performed a loopback test on the serial port to verify it is good.  When I 
power up the the T2 the RX led glows faintly and continuously.  There is no 
initial blink of any of the leds as described in some other posts.  I am 
powering the T2 with a 9VDC 300ma wall wart.  Any ideas on what to try or check 
next?