Is it possible to Split Digital Coax?

Discussion in 'Archived Threads 2001-2004' started by Don Jungwirth, Oct 21, 2002.

  1. Don Jungwirth

    Don Jungwirth Auditioning

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    Is it possible to Split the Digital Coax signal into two separate receivers?
     
  2. AaronBatiuk

    AaronBatiuk Second Unit

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    Yes.

    Use a 75 ohm splitter, the kind used for splitting cable TV coax. You will need to either buy RCA to F-type adapters or replace the RCA connector from one end of each cable with a F-type connector (in order to connect it to/from the splitter). Do not attempt to just use a RCA Y-adapter. This will create an impedance mismatch (two 75 ohm loads connected in parallel is 37.5 ohms; the output impedance is 75 ohms, as is the impedance of the cable), and that can cause problems (signal loss, relflections, etc.).

    Note that in doing this, each output of the splitter will be reduced by about 4 dB (1/2 the input power or -3 dB, plus another -1 dB in losses), or to about 63% of the input voltage. So, the voltage at each receiver will not be 0.7 V (S/PDIF spec), but 0.44 V. This should not cause much of a problem, but it might, especially if the device's output is a little low already.
     
  3. David_Rivshin

    David_Rivshin Second Unit

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    How about using the composite video part of a video distribution amplifier?
    While not originally designed to split digital-coaxial signals, I believe they have the same electrical characteristics. It should maintain the output signal at the same level as the input, and also maintain 75Ohm input and output impedance. I'm sure anyplace like partsexpress or radioshack would have one.

    -- Dave
     
  4. AaronBatiuk

    AaronBatiuk Second Unit

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