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RF Switcher?


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Folks, I'm looking for an RF switcher with multiple inputs and IR remote for some of my old gaming systems that I've not performed any video mods on.  Frankly, some of the mods don't look as good as the clean RF from the console anyway.  My Bally Astrocade, Fairchild Channel F, Intellivision, and some others look great via RF.  But does this mythical RF switching beast not exist?


I don't want an A/B switch like those Radio Shack sold for a while.  I need at least 4 inputs - more would be better.  And I want it to be well shielded.  Heck, if someone had the plans for one I'd build one!


Related question - I see many BNC-connector-based SDI switchers (I could get some adapters to make these work for me) for modern digital TV signals.  And though I think they would function since their bandwidth is much higher, I believe they may induce some delay due to the internal circuitry related to the digital signal processing.  Thoughts?

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You might be able to find what you want by doing a search for "RF multiplexer" as I am sure there must be products out there, however they may be expensive.

I may be wrong but I do not think that an SDI switchers is a good solution as I believe that first you would need to convert the analogue RF into Serial Digital, additionally from a cursory look into SDI it looks like a production format, not a consumer format and so you would need to convert the output to back to RF or to HDMI before you can use it.  


If I wanted such a thing a could not find one, or at least one within my budget I would consider building one using a microcontroller and some Double Pole Double Trow (DPDT) 5V relays. I use Double pole relays to switch both signal and ground to try and avoid any ground loops occurring. Two possibles for the remote are...

1) A simple IR LED and a Photo-transistor connected to the Interrupt on change pin of the microcontroller, every time you press he only button on the remote it selects the next input, the downside is that if you are on 5 out of 8 and want 2 you have to go all the way to 8 and circle around. 

2) I use a microcontroller BASIC called Proton which has a command for reading Sony (and compatible) remote controls that could derive the number of the remote button pressed and therefore be used to directly select which of any 10 inputs (0-9) you want. I have a purchased copy but one of the free to compile devices would probably be suitable.


However, I would probably purchase just one of the intended relays a connect the RF via that first, just to test that the resulting signal quality is OK, I don't know why a relay would affect it but it is best to check before going all in and building the whole thing.   

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