I bought one of these newer dual frequency (1258 and 1280 MHz) 200 mW transmitters and a receiver but did not receive any documentation with the transmitter. The transmitter has four dip switches on it. I received it with switches 1, 2, and 3 in the off position and switch 4 in the on position. These settings seem to have it transmitting on 1258 MHz. I wanted to know how to change it to 1280 MHz. Also do the four switched do anything else. I presume some are basically non functional as this transmitter has some frequencies locked out.