Re: Troubleshooting Channel Vision IR-Over-Coax

["Robert Green" <ROBERT_GREEN1963@xxxxxxxxx>]

"Rob Ivy" <robivy@xxxxxxxxxxx> wrote in message
news:1174260203.998667.261540@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> Hello everyone.  I'm looking for some assistance from those of you
> running an IR-over-coax system in your home.

First thing to do would be to try to get hold of their tech support.

> Here's a summary of my setup: I have Cat6 and coax home run from each
> room in my house back to a rack in my laundry room.  I'm routing cable
> plus modulating 2 Tivos  through a Channel Vision CVT2/8-PIA II
> amplified splitter to 5 TVs.  I have a Channel Vision IR-4000 engine
> attached to one of the 3 unused outputs on the splitter, and I have
> Channel Vision IR-4100 receivers on 4 of the 5 TVs.  I'm using Channel
> Vision IR-2105 targets plugged into the IR-4100s.  I have DC blockers
> on the 2 unused outputs on the splitter, the 5th TV, and the cable
> input to the splitter.  This setup is exactly as depicted in the
> channel vision literature.
>
> Here's the problem:  When any 2 of the IR-2105 targets are plugged in,
> everything works just fine.

Which two?  Your 120' runs or the two shorter runs?

> I can control my Tivos remotely from
> those 2 TVs with no problems.  However, when I plug in the third
> IR-2105 target, the response becomes spotty.  Some signals get through
> but most don't.  When all four IR-2105s are plugged in, there is no
> response whatsoever from any of the 4 locations.  I know that the DC
> is passing to all the targets, because the bright blue indicator bulb
> lights brightly when they receive IR, yet the IR is not making it back
> to the engine.

Have you taken a DC voltmeter to various points on the cable?  That might
tell you if you've got too much of a voltage loss.

> My only thought (and I'm no expert on any of this so this is just
> speculation) is that perhaps there is a limit to how much distance the
> DC can travel without weakening to the point where it can no longer
> carry the IR signal.   My four coax runs where the IR-4100s are
> located are of approx 40ft, 50ft, 120ft, and 120ft, respectively.
> Perhaps the single 12V DC input to the IR-4000 doesn't have the
> horsepower necessary?  The Channel Vision instructions state that 4
> IR-4100s can be run off of a single engine, and that the max distance
> to the engine is 500ft, however it doesn't say if that is 500 feet in
> aggregate or each individual run.
>
> Any help/thoughts/advice is MUCH appreciated, as this is driving me
> nuts.  Many thanks in advance.   -Rob

I would try covering all but one of the receivers at a time, with all four
connected.  With IR setups it's very possible that stray IR light is
overwhelming the system.  One way to check for that is to cover up the
receivers, test, then eventually remove the other three covers, one at a
time.  It might be helpful to cover them with metal cans while testing.  IR
receivers can often pick up stray EMI if the source is close enough. IR
receivers are typically located near strong EMI sources like TV's.

--
Bobby G.