As noted, a composite distribution
system requires a distribution
amplifier (DA) and a separate cable run from that device to each display. An RF distribution
system would require a modulator and some combination of taps and/or splitters (not 'T' or 'Y' connectors), you essentially have a backbone that you tap off of for each
monitor. In both cases the signal amplification required, the appropriate cable type (typically RG-59 or RG-6) and the details of the distribution would be dependent on the actual distribution necessary and factors like
monitor locations and physical relationships, run lengths,
etc. For example, if you have multiple monitors located together with RF distribution then a multi-way splitter or tap may make sense, which would affect the cable run lengths and losses involved.
Personally, I think RF distribution makes sense for your application as running
home run cabling for every
monitor may be impractical. However, there still has to be some thought put into the
system layout. Typically the first step in laying out an RF distribution
system is figuring out where to put taps or splitters to serve the individual displays and where you will use single output or multiple output devices. The difference between a splitter and a tap is that a splitter literally splits the signal, each output is the same and is typically lower than the input
level (-3 to -4dB for a two way split, -6 to -7dB for a four way split and so on), while a tap has one 'through' output with minimal loss (typically around -1dB) and one or more outputs with some greater loss (you select from among several tap values as required). The idea behind taps is that locations further away incur greater losses due to the length of cable and other intervening taps and splitters so in order to try to maintain the same
level at all locations you use taps that insert a desired loss with the tap values or losses typically decreasing as you get further down the
line. That is the general concept of RF distribution design but for a temporary setup it may not be necessary to go into the
level of detail that you might for a permanent
system.
It looks like Radio Shack only carries one
RF modulator,
RF Modulator - RadioShack.com, so I assume that is what you have. That product is apparently intended to connect a video game to a TV, the
manual provides nothing on the output
level, however I doubt it would drive a distribution
system. I don't know what the amp you purchased is but I would guess that an RF
amplifier would be required after the Radio Shack modulator.
For both RF and
composite video distribution, the termination quality can be crucial. You mentioned getting a spool of cable and adding connectors. Nothing wrong with that as long as the connectors are properly terminated meaning the proper strippers and either crimpers or compression tool for the cable and connectors used. Poor terminations will result in poor
image quality.
You might also have to watch where you run cable as if it is above ceilings or in cases,
etc. then you may be dealing with
plenum spaces. If the cable is run in
plenum spaces then it needs to either be in
conduit or
plenum rated cable. Similar for risers between floors, that cable may need to be
riser rated or in
conduit.
