Question for digital TV techs: I would like to inject a source as an input channel between set top box/aerial?

Question

Here is the scenario.

My location: Australia

I am running an LG 5100P HD set top box to receive free-to-air digital channels.

The set top box is connected directly to a Samsung LCD 22" monitor via the set top box's DVI output. Audio is supplied via a mini stereo running off the set top box stereo out.

The problem: Running a monitor without composite video input means that the monitor works great as a TV but I am unable to use alternative sources like DVD players or media players. The set top box has no inputs other than the aerial connector understandably.

Possible solutions I have come up with:

- Put a computer in the mix to run the monitor via its dsub VGA input. _Unpreferred_ solution as I already have computers running. I already have another audiovisual centre and this is for casual living room.

- Buy a Dell 2408WFP which has hdmi, dvi, composite video and component inputs. Easy option but with a AU$720 price tag.

- Buy a composite video to RGB dsub VGA converter to use on VGA input of the monitor. Yuck... c**p resolutions for high price.

My dream solution and the question for anyone technical out there:

Connect something like the old RF modulators used for analog output of game platforms. The dream is that it connect between the aerial plug and the back of the set top box. This dream device would have the capability of creating an input digital channel piggy backed on the signals already received. Perhaps tuned to a couple of alternate channels like the old RF mods used to do.

Your set top box would pick up the alternative input provided by the device as a extra channel beyond those already being received via antenna.

Does anything like this _dream device_ exist? Are there any techs out there who would tell me how possible/impossible this would be to create.

Digital broadcasts obviously use a particular range of frequencies and encoding types. I imagine what I want is quite complex but I can see that it would be a pretty useful tool.

Thanks.

Answer 1

The best solution I can see is to get a AV receiver. This will allow you to add other inputs and use the video processor to up-convert the image to HDMI or DVI. With assignable inputs you could change the audio source easily. I like the model below and will bonus give you 7.1 audio.

As far as your "dream" solution I don't see a pre-made product to help you out. However what you propose is not out of the realm of possible, it just won't be an off the shelf solution. Coupled with the fact that you would need to essentially create the broadcast locally which is not with the reach of the masses.

Good luck.

Answer 2

A standard RF modulator (composite/S-video to RF) should work. They usually provide two channels options 3 or 4.  

You will need also an RF switch at the input of your set-top to switch between antenna and your RF modulator ( an RF mux could work as well).