Bi-directionality in passive equipment?
There are many questions relative to whether a splitter or a tap are bidirectional, mostly when a splitter is used as a mixer. Splitter and mixer can indeed be implemented in a single device, since the RF losses are the same for both directions. The only difference resides in current circulation: since the device is equipped with diodes, circulation is directional. The way a tap works is different, and cannot be considered bidirectional as opposed to a splitter. Tap losses (between input and bridging connection) are not equal to through losses (between output and bridging connection). That is why this circumstance has to be taken into account when figuring out the use of signals in the return channel (5 MHz – 30 MHz).
Given a set of installed series, can the last tap be replaced by a splitter to improved attenuation?
The use of a splitter to replace a tap is not recommended when the different outputs correspond to different users. The reason for this is that the rejection among the outputs of a tap is much higher than the rejection among the outputs of a splitter. Furthermore, any operation performed by a user on its UAP could impact the neighbour sharing that same splitter. Another issue that should be taken into account is the network load. When a tap is installed as the last equipment, a load is inserted on its path so that the whole network is adapted to 75 Ohm. If a splitter is installed instead, the network will not be fully loaded, which will produce impedance mismatches.