[tvlurker]

It's possible that the OP is confusing a two-output splitter (one input and two outputs) with a bi-directional splitter (allows signals to pass in both directions.), and calling the two-output splitter "two-way".

As 57 correctly points out, digital cable requires a working return path in the 5-42 MHz range in order to allow the STB to communicate with the headend. In addition to needing 2-way communication for OnDemand, you also need it for viewing low-demand channels that are delivered via SDV (switched digital video service).

 

[tvlurker]

A 52-1002MHz splitter will not work with a bi-directional cable system, since the cable system's return path is below 52 MHz.

As for the 5-2300MHz device, generally, passive splitters (that means, with no amplification) should be bi-directional. An active splitter (that is one with an amplifier) is NEVER bi-directional unless it explicitly says so.

An easy way to test is to see if any switched video channels work. If you tune to a low-ratings channel in your area, chances are it won't work, and you'll get an error on the screen.
The other way is to look at the diagnostics screen of your Set Top box. If it says "BCAST only" , ( I forgot which field it is, but it's on the first diagnostic page of an 8300), it means you have no return path. You'll have to search for the instruction on how to enter diagnostic mode for your particular Set Top Box.