Fiber plant APC vs UPC... once again...

Jeff Kell jeff-kell at utc.edu
Sat Apr 6 19:17:09 UTC 2013


We are looking into doing cableTV/HFC distribution on campus, and fiber
runs for HFC typically run APC connectors to avoid reflectance on the
analog HFC signal where it is significant.  We we're looking at
converting some existing data UPC to APC for existing runs, and on the
new ones either do a parallel split (UPC and APC) or just stay uniform
(research seems to indicate APC is the winner).

In asking some other groups (EDU LAN managers) I've heard both
extremes... stick with all APC (and jumper APC-to-UPS on gear to data
terminations), and I've heard the exact opposite (UPC is fine, just
jumper UPC to APC at the terminations).  The last time I asked here, the
consensus seemed to be APC was ok, or else do parallel splits.

My best understanding is that going APC across the board, and just using
jumpers (APC to UPC) at the data ends should be fine, and I'm leaning in
that direction.  Are there any significant issues there?  Do APC
terminations "confuse" a data OTDR since you're now missing the expected
reflections?  Other issues?

Before the RFQs go out on the fiber expansion, I'd like to have a clear
goal in mind here :)  Any reason NOT to go APC for the installed fiber
plant and just adjust the terminating jumpers based on the endpoint targets?

Thanks (again),

Jeff





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