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squiffy
2006-03-09, 13:53
To the Squeezebox hardware team...

Any plans to implement a power over ethernet variant of the squeezebox?

If yes, what kind of time frame are we looking at...unless I don't understand the technology properly, it doesn't look like I can just take out a soldering iron and go to town to enable it.

However, as a feature, it would be very handy to have, such that you could place the device anywhere on a CAT5/5e network no other wires would be necessary.

stevieweevie
2006-03-09, 16:06
AFAIK you can buy PoE kit to use with any Ethernet equipment?

Now Power over Wireless would be something I'd subscribe to!

max.spicer
2006-03-10, 04:03
Yeah, wireless electricity is something that's long overdue. Come on Slim, get your act together! :-)

Max


AFAIK you can buy PoE kit to use with any Ethernet equipment?

Now Power over Wireless would be something I'd subscribe to!

Patrick Dixon
2006-03-10, 04:38
Yeah, wireless electricity is something that's long overdue. Come on Slim, get your act together! :-)

Max
It's called 'lightening'.

Stand out on a golf course (with your umbrella up) in a thunderstorm and 'get connected'.

aubuti
2006-03-10, 04:48
Now Power over Wireless would be something I'd subscribe to!

Hmm, time to dig up Nikola Tesla's old notes? http://www.straightdope.com/classics/a3_274.html

jonheal
2006-03-10, 05:52
Just stick the bare wires from one of the ethernet cables coming out of your switch or hub into a wall socket. That should do it. Here, just like thisssdsaseeeee eeiiiiieieiIIIIIIIIEEEEEE!!!!!!

jonheal
2006-03-10, 06:29
Now that we have all had our fun with Squiffy, I started thinking about it.

POTS systems, if I'm not mistaken sent 48V down those skinny wires to ring your phone. Surely those two unused ethernet wires could handle 5 lousy volts at 2 amps.

Some adventurous soul could patch into the cable going to the squeezebox and connect the exisiting transformer to the cable (with some diodes or something to keep the current from running back into the switch/router). Then, a little soldering in the SqueezeBox to patch the two powered ethernet wires to the point where power normally connects to the board. Someone could. But not me. :-)

jimdibb
2006-03-10, 06:48
But which switches/routers actually supply power that way? ALso, I guess
it's convenient, but with so many upgrading powersupplies, how many would
really downgrade to the power that would come over an ethernet cable from
some random switch?

This whole thing brings up an interesting thing from my office. When they
put in wiring for wireless access points, they put 2 ethernet jacks next to
each AP. I figured one was for the signal, and they were goind to run power
through the other one. But when they were done, each one only had a single
wire. This is clearly the technology used.

On 3/10/06, jonheal <jonheal.24gh801141997402 (AT) no-mx (DOT) forums.slimdevices.com>
wrote:
>
>
> Now that we have all had our fun with Squiffy, I started thinking about
> it.
>
> POTS systems, if I'm not mistaken sent 48V down those skinny wires to
> ring your phone. Surely those two unused ethernet wires could handle 5
> lousy volts at 2 amps.
>
> Some adventurous soul could patch into the cable going to the
> squeezebox and connect the exisiting transformer to the cable (with
> some diodes or something to keep the current from running back into the
> switch/router). Then, a little soldering in the SqueezeBox to patch the
> two powered ethernet wires to the point where power normally connects
> to the board. Someone could. But not me. :-)
>
>
> --
> jonheal
>
> Jon Heal says:
> Have a nice day!
> http://www.theheals.org/
> ------------------------------------------------------------------------
> jonheal's Profile: http://forums.slimdevices.com/member.php?userid=2133
> View this thread: http://forums.slimdevices.com/showthread.php?t=21936
>
>

pfarrell
2006-03-10, 06:52
Jim Dibb wrote:
> But which switches/routers actually supply power that way?

More and more every day. It is the coming thing, as you more than
save a wire, you have one less thing to worry about.

> guess it's convenient, but with so many upgrading powersupplies, how
> many would really downgrade to the power that would come over an
> ethernet cable from some random switch?

No audiophile would use it, but it is really convenient.


> This whole thing brings up an interesting thing from my office. When
> they put in wiring for wireless access points, they put 2 ethernet jacks
> next to each AP. I figured one was for the signal, and they were goind
> to run power through the other one. But when they were done, each one
> only had a single wire. This is clearly the technology used.

There are four spare pairs in most CAT5/6 systems.
Reducing part counts is a big deal for manufacturers.
While the hated wall wart is cheap, it is far cheaper
to not have it at all.


--
Pat
http://www.pfarrell.com/music/slimserver/slimsoftware.html

jimdibb
2006-03-10, 06:55
Very interesting. Thanks

On 3/10/06, Pat Farrell <pfarrell (AT) pfarrell (DOT) com> wrote:
>
> Jim Dibb wrote:
> > But which switches/routers actually supply power that way?
>
> More and more every day. It is the coming thing, as you more than
> save a wire, you have one less thing to worry about.
>
> There are four spare pairs in most CAT5/6 systems.
> Reducing part counts is a big deal for manufacturers.
> While the hated wall wart is cheap, it is far cheaper
> to not have it at all.
>
>
> -

jonheal
2006-03-10, 08:06
But which switches/routers actually supply power that way? ALso, I guess
it's convenient, but with so many upgrading powersupplies, how many would
really downgrade to the power that would come over an ethernet cable from
some random switch?

This whole thing brings up an interesting thing from my office. When they
put in wiring for wireless access points, they put 2 ethernet jacks next to
each AP. I figured one was for the signal, and they were goind to run power
through the other one. But when they were done, each one only had a single
wire. This is clearly the technology used.

On 3/10/06, jonheal <jonheal.24gh801141997402 (AT) no-mx (DOT) forums.slimdevices.com>
wrote:
>
>
> Now that we have all had our fun with Squiffy, I started thinking about
> it.
>
> POTS systems, if I'm not mistaken sent 48V down those skinny wires to
> ring your phone. Surely those two unused ethernet wires could handle 5
> lousy volts at 2 amps.
>
> Some adventurous soul could patch into the cable going to the
> squeezebox and connect the exisiting transformer to the cable (with
> some diodes or something to keep the current from running back into the
> switch/router). Then, a little soldering in the SqueezeBox to patch the
> two powered ethernet wires to the point where power normally connects
> to the board. Someone could. But not me. :-)
>
>
> --
> jonheal
>
> Jon Heal says:
> Have a nice day!
> http://www.theheals.org/
> ------------------------------------------------------------------------
> jonheal's Profile: http://forums.slimdevices.com/member.php?userid=2133
> View this thread: http://forums.slimdevices.com/showthread.php?t=21936
>
>

Anyway, I wasn't talking about "real" Power Over Ethernet (PoE). I was describing jury-rigging something that just piggy-backed on that last length of cable between the switch and the SqueezeBox. I think the real PoE systems are sort of standardized on 48V. And I guess there are actually 4 free wires in the ethernet cable.

Jacob Potter
2006-03-10, 08:17
On 3/10/06, jonheal
<jonheal.24glun1142003401 (AT) no-mx (DOT) forums.slimdevices.com> wrote:
> Anyway, I wasn't talking about "real" Power Over Ethernet (PoE). I was
> describing jury-rigging something that just piggy-backed on that last
> length of cable between the switch and the SqueezeBox. I think the real
> PoE systems are sort of standardized on 48V. And I guess there are
> actually 4 free wires in the ethernet cable.

The standardized version of PoE (802.3af) doesn't actually need to use
the extra pairs. Ethernet uses isolation transformers, so it's
possible to combine power and signal by putting a DC voltage between
the two pairs.

- Jacob

squiffy
2006-03-10, 09:30
Jim Dibb wrote:
> But which switches/routers actually supply power that way?

More and more every day. It is the coming thing, as you more than
save a wire, you have one less thing to worry about.

> guess it's convenient, but with so many upgrading powersupplies, how
> many would really downgrade to the power that would come over an
> ethernet cable from some random switch?

No audiophile would use it, but it is really convenient.


> This whole thing brings up an interesting thing from my office. When
> they put in wiring for wireless access points, they put 2 ethernet jacks
> next to each AP. I figured one was for the signal, and they were goind
> to run power through the other one. But when they were done, each one
> only had a single wire. This is clearly the technology used.

There are four spare pairs in most CAT5/6 systems.
Reducing part counts is a big deal for manufacturers.
While the hated wall wart is cheap, it is far cheaper
to not have it at all.


--
Pat
http://www.pfarrell.com/music/slimserver/slimsoftware.html


I wasn't thinking this would generate so much debate and fun ;-)

Regardless, since I run 192 kBit/sec MP3's "audiophile" quality is not my reason for this...convenience and wiring layout is.

If audiophile listening and making my friends drool and my own eyes bleed with quality were the reason, I'd dust off my Revolver turntable and Mirage loudspeakers and drag my knuckles over to my milk crates of vinyl and listen to Jazz at the Pawnshop.

All sarcasm aside, Pat and group, the feedback was interesting. However, unless you are listening to FLACs, if the wiring was done correctly, I don't see how any line AC hum would percolate through to the listening environment unless the volume crept up, since its essentially a 48 VDC regulated system.

I plan on looking through the IEEE specs a little more and seeing if some vanilla PoE hardware would work "out of the box". Where I live, the renovations I have in mind will require an electrical permit IF extra outlets and power installation is necessary. If I do PoE, running extra CAT5 cable is a piece of tasty cake.

Hmmm, PoE with those sprinkles on them....gurgle (like Homer).

Squiff

Philip Meyer
2006-03-10, 12:16
>However, as a feature, it would be very handy to have, such that you
>could place the device anywhere on a CAT5/5e network no other wires
>would be necessary.
>
You wouldn't hear much ;)

I'd doubt it would be cost effective for SlimDevices to market a PoE unit. I imagine most users put their SB on a HiFi, where power sockets are required for the HiFi anyway, and where there is no CAT5 network access.

Phil

Fred
2006-03-10, 16:33
POTS systems, if I'm not mistaken sent 48V down those skinny wires to ring your phone. Surely those two unused ethernet wires could handle 5 lousy volts at 2 amps.

PoE is also 48V and the reason why it is the voltage loss in the cable. You could send 5V at the source but end up with 4V at destination if the cable is long (40 feet and above).
Cable gauge on the other hand determines how much amps you can put through and I am not sure the tiny ethernet wire could stand 2 amps.
So the 5V, 2A idea might not work...

Now what the SqueezeBox wants is 10W (5V*2A) so at 50V, it is only 0.2amp and that goes well into the tiny cable, and the 1V drop from 48V to 47V is not that dramatic.

Voila for the theory :-)

Fred

b0lt
2006-03-10, 20:42
You mean like this?
http://www.fiftythree.org/etherkiller/img/etherkiller.jpg
>:D

kmccourt
2006-03-10, 23:18
PowerDsine make a range of 'splitters' to deliver power to non-compliant/pre-802.3af equipment. There are several models that deliver 5V/2.2A and I think they differ only in the DC connector at the end.

http://www.powerdsine.com/Products/Midspan/Splitters/

Does anyone know if any of the connectors listed above would fit a SB or would a bit of DIY to fit a new one be required?

Bart
2006-05-05, 13:06
PoE is also 48V and the reason why it is the voltage loss in the cable. You could send 5V at the source but end up with 4V at destination if the cable is long (40 feet and above).

Is this why my attempts at POE have not worked? I have wired up a socket at one end and a plug at the other and my voltmeter tells me I am sending the current across with an almost imperceptible voltage drop. Every device I connect (PC, clock radio, phone charger) works as expected but two Squeezeboxes just won't play - don't start, just sit there with a blank screen.

kdf
2006-05-05, 13:18
Quoting Bart <Bart.27cp2n1146859801 (AT) no-mx (DOT) forums.slimdevices.com>:

> Is this why my attempts at POE have not worked? I have wired up a
> socket at one end and a plug at the other and my voltmeter tells me I
> am sending the current across with an almost imperceptible voltage
> drop.

Is that measuring with or without the squeezebox connected? .
-k

Bart
2006-05-05, 14:38
Is that measuring with or without the squeezebox connected? -k
Without it connected - when I measure it with the squeezebox connected it does, indeed, drop by .6v
Would this be enough to stop it working?
If I could find a 6v power supply rated at about 1.5 - 2A would it be safe to use it?

Michaelwagner
2006-05-05, 17:28
But isn't this all backwards?

Where you put your SB usually has power and no ethernet. So what's needed from Slim as a neat addition to their line is ethernet over power, not the other way 'round.

There are standard chip sets for it, I use them as separate boxes, but if they were built into the SB (or optionally integrated, like the wireless SBs), there'd be one less wire and no ethernet cabling hassles.

Or am I missing something?

snarlydwarf
2006-05-05, 17:33
Actually, they need to provide power and ethernet wirelessly.

cf the works of Tesla.

(Though, no doubt, the sound will annoy some audiophiles and the people who think the display is too bright now might be annoyed, but that's the price to pay for truly wireless sound. Oh, yeah, and it would make the SB3 portable.)

Mark Lanctot
2006-05-05, 17:40
Actually, they need to provide power and ethernet wirelessly.

cf the works of Tesla.

(Though, no doubt, the sound will annoy some audiophiles and the people who think the display is too bright now might be annoyed, but that's the price to pay for truly wireless sound. Oh, yeah, and it would make the SB3 portable.)

...and have side effects noted in the movie "The Philadelphia Experiment". ;-)

Michaelwagner
2006-05-05, 17:54
Ok, if we're going to be really silly, why don't we put solar cells on the top of the SB and a little battery recharger for night time and not have a wall wart at all.

The solar cells could also extend over the top of the display like a glare shield for really bright days when you can't read the display well.

Michaelwagner
2006-05-05, 18:00
http://www.siliconsolar.com/shop/catalog/Flexible-Solar-Battery-Charger-SolLite-4AAE-p-16200.html

tyler_durden
2006-05-05, 18:35
POE in the SB would only be half of the story. You still need a source that can provide the 10 Watts or so. I haven't seen a lot of 10W POE sources being built into PCs yet.

TD

kdf
2006-05-06, 11:30
On 5-May-06, at 2:38 PM, Bart wrote:

>
> kdf Wrote:
>> Is that measuring with or without the squeezebox connected? -k
> Without it connected - when I measure it with the squeezebox connected
> it does, indeed, drop by .6v
> Would this be enough to stop it working?

it would seem from your results thus far, that it is.

> If I could find a 6v power supply rated at about 1.5 - 2A would it be
> safe to use it?
>
unfortunately, I can't say anything for certain on that either. I
don't know what the upper limits are on the supply voltage. Likely
sean has posted this elsewhere before, but you could also try asking on
the diy forum. My guess is that forum is just for problems like this.
As a general rule, being over by only 400mV 'should' be safe, but it is
best still to give a bit of time for the right person to answer rather
than risk your squeezebox against the possibility of intolerant
components.
-k

Michaelwagner
2006-05-06, 12:06
when I measure it with the squeezebox connected it does, indeed, drop by .6v
Would this be enough to stop it working?
If I could find a 6v power supply rated at about 1.5 - 2A would it be safe to use it?
If I did my figuring right, this means you have roughly .6 ohms of resistance in that wire. That seems like a lot. How long is that wire?

IIRC, only 4 of the 8 wires in an ethernet cable are used, so you could use the other 4 instead of only using 2, and you'd drop your voltage drop roughly in half.

But I have to say this isn't a really good idea. Having a resistor in series with your power supply is going to introduce noise in your audio out. At the very least, you should probably be putting some sort of electrolytic capacitor at the SB end (although I seem to recall, on pictures of the SB circuit board, that there is a fair sized one on the input side).

Bart
2006-05-07, 02:45
unfortunately, I can't say anything for certain on that either. I don't know what the upper limits are on the supply voltage. -k
Then it occurred to me that I had also run some heavy speaker cable to the same point, so I sent the power down that and the squeezebox is happy.

IIRC, only 4 of the 8 wires in an ethernet cable are used, so you could use the other 4 instead of only using 2, and you'd drop your voltage drop roughly in half.
But I have to say this isn't a really good idea. Having a resistor in series with your power supply is going to introduce noise in your audio out.
I shall try using all the wires, although it is working now, using the speaker wires. The audio on this squeezebox is not connected, only one is conected and the others are synchronised to that, so I wouldn't notice any noise in the audio out...

Michaelwagner
2006-05-07, 04:23
yes, speaker wires are good big fat copper pipes. Should have low voltage loss over those :-)

rock
2006-05-08, 09:41
I built my own POW system that simply used the remaing 4 wires to send 5V to my networked camera. But, as is the theme in this thread it was only good for about 40feet.

So I bought one of these:

http://www.dlink.com/products/?sec=0&pid=332

Actually I bought the DWL-P100 which I think is the same animal but only 5V. Works like a charm. I bet It'd work with the SB as well although you may have to re-jigger the size and polarity or the power plug.

I'd give it a shot for you, but my DWL-P100 is quite busy right now and installed in an inconveniently remote location.

Michaelwagner
2006-05-09, 04:27
cool unit.

The power sent over the ethernet wires is 48 volts, to cut down on power loss, and then there is some kind of voltage reducer at the far end. Probably a regulator, possibly a chopper/switcher followed by a regulator, hard to tell from the docs.

GatoChulo
2006-05-11, 18:22
So random note,

I live in a really rural location and the only two Internet options available to me when I moved in were DirecPC and what is called 'Fixed Wireless'.

I opted for the fixed wireless due to the initial and monthly cost and upon installation, I find the man plugging one single ethernet cord from the rooftop antenna into what he called a 'power injector' then onto my router & network. His homemade contraption merely spliced the power to run the wireless antenna on the roof BEFORE any of my router and network equipment.

Have been using it for 3 years solid and LOVE IT! Power over ethernet ROCKS.

Peace,
Joe.m

jmpage2
2006-05-12, 07:58
So random note,

I live in a really rural location and the only two Internet options available to me when I moved in were DirecPC and what is called 'Fixed Wireless'.

I opted for the fixed wireless due to the initial and monthly cost and upon installation, I find the man plugging one single ethernet cord from the rooftop antenna into what he called a 'power injector' then onto my router & network. His homemade contraption merely spliced the power to run the wireless antenna on the roof BEFORE any of my router and network equipment.

Have been using it for 3 years solid and LOVE IT! Power over ethernet ROCKS.

Peace,
Joe.m


So what exactly are you saying, that you bypassed the switch so that PoE was being injected directly into your network instead of going through the bypass device?

And what exactly are you "rocking" with PoE? There are very few devices that utilize it today, and some equipment can actually be damaged of power is present on either paiirs 2,3 or 7,8. I've seen PoE fry a $15,000 Agilent ethernet test set that was designed at a time when power over ethernet did not exist.