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tcgerhard
2008-04-15, 18:44
I'd like to use my SB3 to bridge the network connection from my DirecTV DVR (HR21) to my wireless network; the DVR's manual mentions "This socket provides 5 Volts DC Power. Please ensure your equipment is compatible prior to connection."

I'm assuming the 5V refers to the detection voltage used to sense compatibility with PoE, but don't know that for a fact.

Is connecting this device to my SB likely to create any problems?

Thanks.

seanadams
2008-04-15, 20:30
I'd like to use my SB3 to bridge the network connection from my DirecTV DVR (HR21) to my wireless network; the DVR's manual mentions "This socket provides 5 Volts DC Power. Please ensure your equipment is compatible prior to connection."

I'm assuming the 5V refers to the detection voltage used to sense compatibility with PoE, but don't know that for a fact.

Is connecting this device to my SB likely to create any problems?

Thanks.

This doesn't make any sense. Can you provide some more context for that quote from the DTV manual?

SB3 does not use POE, but it is fine to connect it to a POE switch. However, I suspect those comments have nothing at all to do with POE, and may have been referring to some other connector.

If it is in fact 5v then it is non-standard and must be intended to support some special DTV hardware. Standard POE is 48V.

tcgerhard
2008-04-16, 04:20
I'm thinking that the DTV device wants to act like a PoE switch, probably for some future application that they have in mind. From what I read about PoE, there is an initial voltage of 2-10v used to sense whether it's OK to turn on the 48v; I'm guessing the 5v is for that purpose.
I did connect the DTV box to an old hub with one working port (and now heading to the trash...), the link came up fine with no apparent damage to the hub.
If the SB3 is fine connected to a switch with PoE, I'll give it a try tonight.
Thanks.

peter
2008-04-16, 04:38
tcgerhard wrote:
> I'm thinking that the DTV device wants to act like a PoE switch,
> probably for some future application that they have in mind. From
> what I read about PoE, there is an initial voltage of 2-10v used to
> sense whether it's OK to turn on the 48v; I'm guessing the 5v is for
> that purpose.
> I did connect the DTV box to an old hub with one working port (and now
> heading to the trash...), the link came up fine with no apparent damage
> to the hub.
> If the SB3 is fine connected to a switch with PoE, I'll give it a try
> tonight.
>

One of my SB3's is connected to a POE enabled switch (endspan).
This causes no problems (but has no advantages either).

POE (802.3af) is designed to co-exist with non-POE enabled network clients.

Regards,
Peter