I had already installed a generic ELT a couple of years ago, but recently a new advanced model has been released and will become mandatory in a few years and I decided to upgrade now when the aircraft is more accessable. The new model will transmit position on 121.5 and 406 MHz which can be picked up by satellite which will be more accurate and timely in the event of a crash. Ameri-king makes it easy as the new 451 model uses most of the hardware from the old model so replacement is relatively easy.
The new ELT fits into the old mount and also uses the same antenna and monitor wiring, so replacing the ELT unit was simple. I had to reposition the antenna mount as this did change slightly, and this required me to me make the mounting bracket.
