Main body of this page still under construction.
Battery-Independent FPP Modification
The HT1550 will normally allow FPP with a special "red battery" attached which contains a chip allowing FPP. This can be bypassed by editing and re-flashing the radio with modified firmware.
The information for modifying the firmware on the HT1550 was discovered by the user Mars from the site communications.support and the modified firmware file is available for download here.
This file will need to be flashed to the radio using a valid flash cable and modified flash software, available elsewhere on the W9CR Wiki.