There is a cable television line that enters from outside into our basement.
The first device the cable connects to is an in-line Viewsonics VSGB1GTSS.
The Viewsonics VSGB1GTSS is not a line splitter, so I'm assuming it's a
signal booster of some kind. The second device the cable connects to is a
Signal Vision 2-way splitter SV-2G 5-1000MHz, with two 3.5dB outputs.

My goal is to run a third cable line off this line. Thus, I will need to
change the 2-way splitter to a 3-way splitter. Is Cannel Vision a good brand
for a 3-way splitter? Will I need to change the Viewsonics VSGB1GTSS to
match the 3-way splitter?