How to split coaxial cable tv?

Can I split a HDMI signal, convert it to coax cable and have the TV still be able to use it with decent strength?

• So, Comcast TV boxes used to have an HDMI Out and a Cable Out, and I made use of them both on my TV; HDMI In for watching regular TV, and Cable In for watching Picture-In-Picture TV while I use my laptop on the HDMI In.Visual representation, in case that made no sense in word form;http://orig05.deviantart.net/5a52/f/2015/139/1/a/untitled_by_whyme777x-d8u1h6e.png(Before anyone mentions that there's two HDMI inputs, PIP isn't able to use the HDMI signals next to each other, the small one HAS to be Cable)Unfortunately, these new boxes ONLY have HDMI Out. So my question is, can I use the one HDMI Out, attach a HDMI 2-splitter plus a HDMI->COAX converter on one branch after it, and will it still have a signal strong enough and of the right format that my TV can use and still have decent picture? AND, will Comcast's equipment detect the reduced signal strength and shut down on me? -.-''I don't have the money to burn on a failed experiment, so trial and error is out of the question :(

• Answer:

  I would suggest you contact Comcast tech support for this so that they can give you better suggestions and avoid yourself away from the risk.