Can I use a 1-mm core fiber with the multimode versions of the Models 15XX and 14XX?
The fiber in the multimode versions has a 50-µm core and so the coupling efficiency from your 1-mm core fiber to the internal 50-µm core fiber will be very poor. One option is to use the free-space versions of these receivers. In this case, you will have to couple the light out of the 1-mm core fiber and then focus the light onto the 25-µm diameter active area.
