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Reliable Sci Atl Cable Box power control?

Here in Vegas Coz cable is constantly changing things with the firmware on the scientific Atlanta AND Cisco cable boxes. Last I checked, the power-on-with-numeric option had been removed. I was wondering what works better to verify power status on these boxes - a power current sensor or a video sync sensor. I ask this because most of the boxes we work with are DVRs, so the hard drives are always on, pulling power. Thanks.

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    viningvining Posts: 4,368
    Most of those boxes have a switched outlet on the back. In settings make sure the outlets power is set to on with the box not always on Plug in a 12vdc xformer into it and i like to epoxy an isolation relay with a built in signal diode, http://www.altronix.com/index.php?pid=2&model_num=RB610, on the back and then to an IO port.

    FYI, The link show a board of 6 relays that snap apart into single boards.

    The plug in xfomer 12vdc leads go to the relays control coil terminal and the isolated relay contact terminals go to the IO.
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    John NagyJohn Nagy Posts: 1,734
    The IO ports can take raw 5 to 12vdc instead of a relay closure, simplifying the use of a small wall wart with no relay required. The smaller and lower wattage the better, but the IO port is designed to hold up under many milliamps.

    FYI, the IO ports also OUTPUT a small voltage when programatically turned on. Enough current to run those same breakaway relays. So you can use the external relays attached directly to the NetLinx IO ports and get high-current relay action with very little effort.
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    viningvining Posts: 4,368
    Personally i like to isolate when ever easy and practical. This may not be all that practical but it stems from when we used the Niles light sensor which had a built in power supply and output voltage so when the coil's field collapsed (no light) the the IO port would freak out until coil completely discharged. We've been using them for everything ever since and never gave it any thought when we stop using the light sensor and started using the switcheg outlet.

    Here's a good link with IO info.

    http://www.amxforums.com/showthread.php?1258-What-are-IO-ports-for&highlight=Signal+diode
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    DHawthorneDHawthorne Posts: 4,584
    It's been a while since I've seen a Scientific Atlanta box that the switched outlet actually was switched, even though set that way in the box options. I've not been able to come up with a reliable way to turn them on automatically, and have resorted to giving customers a power button: "if you don't see a picture, press this button."
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    John NagyJohn Nagy Posts: 1,734
    This turns into another case where the better product, a cable TIVO, isn't selected because the one from the cable company is cheaper. Then the integrator spends hours on unsatisfying workarounds, and in the end the customer pays more for less.
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