RF splitters

Discussion in 'Archived Threads 2001-2004' started by Yee-Ming, Aug 1, 2002.

  1. Yee-Ming

    Yee-Ming Producer

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    anything in particular I should look out for in buying one?

    I am thinking of splitting the RF "aerial" entering my living room into two, one to connect direct to the TV, and the other to the cable tuner box, so that I can still use PIP when at least one is terrestrial TV.

    I've seen a S$6 one which looks like a T-shaped pipe-junction, which simply screws onto the socket and provides two output sockets, and an S$18 one with a small cable to attach to a metal block with one input and three output sockets. any thoughts?
     
  2. Jonathan Smith

    Jonathan Smith Stunt Coordinator

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    I had a setup just like your for using the PIP on our TV. It all depends on your cable service, but many times your signal will look pretty bad after you split it. One solution is to buy an integrated splitter/amplifier, but I ended up having problems even with that (our cable is digital, and the signal going to the digital box still got degraded enough that it caused a lot of noise).

    I have abandoned the PIP altogether now since I don't really consider it very useful. If you want to give it a go, I'd say your best shot is a splitter/amp so you don't lose signal strength. They have them at Radio Shack btw.

    Good luck.
     
  3. Dimitrios Stathopoulos

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    A couple of things to be careful of with a splitter is reducing your RF level into the tuner. That splitter is going to have about 4-5 dB of loss. I know they are labled as 3.5 dB loss but that isn't then whole picture. The total loss is the splitting loss and the losses through the transformer and windings. So typically you will see about 3.5 dB in splitting loss and another 1dB of loss for I2R losses.

    Also make sure you match the impedance of your devices, ariels are typically 300 ohms and that splitter and your tv's tuner input is a 75 ohm device, so you might have to get a balun or some other sort of impedance matching device.

    Also you have to be careful how and where you install one of these inline amplifiers, if you hit your tuner with too much gain then you can saturate the mixer used in the cable tuner.

    ds
     
  4. Yee-Ming

    Yee-Ming Producer

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    whoa. looks like I'm stepping into a minefield here in considering doing this.

    I thought a simple "mechanical" split, much like a Y-lead, might be sufficient? that's what the two things I described in my first post appear to be, at least to my uninformed mind. if I do go that way, after the split the "standard" 1m or so cables would be attached to the two output splits and to the respective devices (TV and cable box), the split is not intended to convey the signal to another room or such (which I can see might lead to concerns about signal degradation).

    whew, looks like I need to read up a bit on electronics. can't remember my high school physics anymore...
     

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