Hi! If you have used a TC35 GSM modem I need some info such as maximum voltage, current ratings, how you interfaced it to a circuit other than using the DC jack & the serial port. I'm facing some difficulties when interfacing.
I gave about 10V to the 3rd Vcc pin. Now it only shows only a Red light. Could it be burn ? The shop's website which I purchase it, states that it supports 5-24V. Is it only for the DC jack ?
Are you talking about the TC35 module or TC35 connected through the interface board shown on your photo? For the module, there's a Siemens hardware manual, for the interface board, ask your local vendor respectively the board manufacturer.