OFFICIALLY, the external drive must have its own power source. I believe the Passports are powered by the USB connection and that is NOT officially supported/recommended. Now, some on this forum have and still use USB connection to power the drive and have no problems to report.
Remember, the STB is powering your entire system which includes the switches and LNBF's at your reflector or reflectors. They are different configurations for each install. Some may be simple and looking at only 2 or 3 satellites or some looking at 4 or 5. Also, the Dish OTA Module is powered by the Hopper, NOT an external power source. This means that Dish does not want to overtax the Hopper with power demands not approved, and Dish may have other future devices they may design to use USB connection power rather than external power. So, Dish, for reasons Engineering has, does NOT want any USB powered HDD's connected to any of its boxes. I remember a past Tech Forum where they stressed again, using external power only, but not much explanation why.
OK. Bottom Line: Knowing Dish's official and approved external HDD's to be used with ANY of its boxes, the risk is your to take. One could see a situation where the box will no longer power the USB powered HDD if there are more demands or if the box is failing. You may lose your recordings. Also, if the USB powered HDD provides a tipping point in power demand, it could, in theory, cause problems with your LNBF's reliability, and even slowly kill them or other parts of your system. And each external HDD may have different power needs than another, so we don't know if a less power demanding USB powered external HDD is a better fit than a more power demanding USB powered HDD.
Knowing the risks, do what you want. As I pointed out, some are using USB external HDD with no problems, and they probably have an install that is not that demanding.
Personally, if a manufacturer takes pains to get the word out (from every instruction I have seen and Tech Forum stressing it), I err on their side, so, in my case, all my external HDD's have their own power source.
I think Dish wants to be certain that EVERY subscriber will always have reliable power for their external HDD that is not limited to certain installs that have more power demands than others. I think the engineers just want the ViP's and Hoppers to, ideally, power the SYSTEMS ONLY (and there are some switches that "should" be externally powered at all times such as the DPP44, while, on the other hand, the box can power different DP or DPP switches) and, of course, the Dish USB OTA using the box for power. From an engineers point of view, this ensures reliably powered external HDD's in all installs without taxing the box, weather some installs can handle powering the USB powered HDD or not, and provides for upgrades to your system with parts that NEED the box for its power. This way, everything is covered for reliability. Disks spinning up do take a surge of power the box, in some cases, may not be able to handle properly.
It's your decision, your risk. It's your programming to keep or lose. Your system to have one part to work buggy or just fail and deal with any inconveniences, or you could experience no problems for a very long time. Let us know what you decide.
