The pinout for the 2N3904 and the 2N2222A is shown below. In order to correctly insert the 2N2222A into the circuitboard you must bend the BASE pin between the EMITTER and COLLECTOR. Just remember the tab on the 2N2222A is closer to the EMITTER and the EMITTER pad is always square. Verify you have it inserted correctly otherwise the transmitter will not work.