I have a Netgear Switch (GS108) that has been running 24/7 for around 8
years.

The other week it stopped working with all the lights lit up but no activity
going through it.

On searching the web for any clues I came across 1 or 2 posts referring to
"dodgy" power supplies. So before binning the switch, I swapped the power
supply for another Netgear one.
However the original power supply was 12V and the one I was trying was only
5V. To my astonishment it worked.

So I ordered a new 12V exact replacement for the original power supply. It
arrived today but the switch is exactly the same. The lights all light up
but no activity.

I can't understand what the problem is?
The switch is marked 12V, the original power supply and replacement power
supply are both 12V but they don't operate it.
Yet the 5V power supply appears to operate it just fine.

Will I be damaging either the Switch or the 5V power supply by using them
together?
Anyone know why the 12V power supply isn't able to work it correctly even
although it is certainly able to power it?!?!

Cheers.

Steven Campbell wrote:

I have a Netgear Switch (GS108) that has been running 24/7 for around 8
years.

I have one of those.

The other week it stopped working with all the lights lit up but no
activity going through it.

On searching the web for any clues I came across 1 or 2 posts referring to
"dodgy" power supplies. So before binning the switch, I swapped the power
supply for another Netgear one.
However the original power supply was 12V and the one I was trying was
only 5V. To my astonishment it worked.

So I ordered a new 12V exact replacement for the original power supply. It
arrived today but the switch is exactly the same. The lights all light up
but no activity.

I can't understand what the problem is?
The switch is marked 12V, the original power supply and replacement power
supply are both 12V but they don't operate it.
Yet the 5V power supply appears to operate it just fine.

Will I be damaging either the Switch or the 5V power supply by using them
together?
Anyone know why the 12V power supply isn't able to work it correctly even
although it is certainly able to power it?!?!

Cheers.

Not sure. But I did have something like your problem happen - got it swapped
under warranty, so I never investigated it.

I *would* have thought most of the logic is expecting 5V or less. Perhaps
the internal regulator has gone short circuit - in which case, I'm quite
surprised it hasn't fried. Unless the regulator has gone to some
intermediate state of dodginess?...

If it's a bin it job, but a 5V supply seems to work, I'd go with that - but
monitor it closely for a day and see if anything smells hot.

--
Tim Watts

"Steven Campbell" wrote in message
o.uk...
I have a Netgear Switch (GS108) that has been running 24/7 for around 8
years.

The other week it stopped working with all the lights lit up but no
activity going through it.

On searching the web for any clues I came across 1 or 2 posts referring to
"dodgy" power supplies. So before binning the switch, I swapped the power
supply for another Netgear one.
However the original power supply was 12V and the one I was trying was
only 5V. To my astonishment it worked.

So I ordered a new 12V exact replacement for the original power supply. It
arrived today but the switch is exactly the same. The lights all light up
but no activity.

I can't understand what the problem is?
The switch is marked 12V, the original power supply and replacement power
supply are both 12V but they don't operate it.
Yet the 5V power supply appears to operate it just fine.

Will I be damaging either the Switch or the 5V power supply by using them
together?
Anyone know why the 12V power supply isn't able to work it correctly even
although it is certainly able to power it?!?!

Cheers.



I expect that the switch has a 5V regulator inside that has gone short.

Steve S

"Tim Watts" wrote in message
...
Steven Campbell wrote:

I have a Netgear Switch (GS108) that has been running 24/7 for around 8
years.

I have one of those.

The other week it stopped working with all the lights lit up but no
activity going through it.

On searching the web for any clues I came across 1 or 2 posts referring
to
"dodgy" power supplies. So before binning the switch, I swapped the power
supply for another Netgear one.
However the original power supply was 12V and the one I was trying was
only 5V. To my astonishment it worked.

So I ordered a new 12V exact replacement for the original power supply.
It
arrived today but the switch is exactly the same. The lights all light up
but no activity.

I can't understand what the problem is?
The switch is marked 12V, the original power supply and replacement power
supply are both 12V but they don't operate it.
Yet the 5V power supply appears to operate it just fine.

Will I be damaging either the Switch or the 5V power supply by using them
together?
Anyone know why the 12V power supply isn't able to work it correctly even
although it is certainly able to power it?!?!

Cheers.

Not sure. But I did have something like your problem happen - got it
swapped
under warranty, so I never investigated it.

I *would* have thought most of the logic is expecting 5V or less. Perhaps
the internal regulator has gone short circuit - in which case, I'm quite
surprised it hasn't fried. Unless the regulator has gone to some
intermediate state of dodginess?...

If it's a bin it job, but a 5V supply seems to work, I'd go with that -
but
monitor it closely for a day and see if anything smells hot.

Cheers. I've been running it for the last week with the 5V power supply and
all seems fine. I just didn't want to fry the power supply as its for my
Netgear Access point that I'm not needing just now.

"Steve S (another one)" wrote in message
...

"Steven Campbell" wrote in message
o.uk...
I have a Netgear Switch (GS108) that has been running 24/7 for around 8
years.

The other week it stopped working with all the lights lit up but no
activity going through it.

On searching the web for any clues I came across 1 or 2 posts referring
to "dodgy" power supplies. So before binning the switch, I swapped the
power supply for another Netgear one.
However the original power supply was 12V and the one I was trying was
only 5V. To my astonishment it worked.

So I ordered a new 12V exact replacement for the original power supply.
It arrived today but the switch is exactly the same. The lights all light
up but no activity.

I can't understand what the problem is?
The switch is marked 12V, the original power supply and replacement power
supply are both 12V but they don't operate it.
Yet the 5V power supply appears to operate it just fine.

Will I be damaging either the Switch or the 5V power supply by using them
together?
Anyone know why the 12V power supply isn't able to work it correctly even
although it is certainly able to power it?!?!

Cheers.



I expect that the switch has a 5V regulator inside that has gone short.


Ah right, that makes sense if I've got this right?
12V is being supplied but it gets changed to 5V inside the Switch?
The regulator isn't working correctly so hence why the 12V power supplies
don't operate it.
Makes you wonder why they needed a 5V regulator inside and they couldn't
just supply a 5V power supply.

I wonder if that is why all the recent GS108's come with a 7V power supply!

On Aug 20, 10:30*pm, "Steven Campbell" wrote:
"Steve S (another one)" wrote in ...
Makes you wonder why they needed a 5V regulator inside and they couldn't
just supply a 5V power supply.

They probably had a good deal on 12v supplies -- the 5v regulator
inside would cost only a few pence, whereas they could save a lot by
ordering tens of thousands of 12v supplies rather than a more limited
number of 12v and 5v and who knows what else in between. Makes sense
to standardise on the highest voltage required by any of the line of
items which might require a smallish power supply.

On Fri, 20 Aug 2010 22:30:22 +0100, Steven Campbell wrote:

12V is being supplied but it gets changed to 5V inside the Switch?

Is it 12v AC or DC? Some wallwarts are nothing more than a
transformer and they feed a nominal voltage of AC to the equipment
that then makes the DC rail(s) it wants.

Makes you wonder why they needed a 5V regulator inside and they couldn't
just supply a 5V power supply.

Economies of scale combined with international sales. If you are
buying 100,000 wallwarts and 12v ones are 10p cheaper than 5v ones...
Also to deliver the same power you'll need a heavier connecting cable
with the lower voltage supply to avoid to much loss in the cable. 10W
at 12v is 0.8A, 10W at 5v is 2A.

I wonder if that is why all the recent GS108's come with a 7V power
supply!

Thats does sort of point a finger at 12v stressing the internal
regulation of the unit rather more than was expected.

--
Cheers
Dave.

On Fri, 20 Aug 2010 21:59:05 +0100, Steven Campbell wrote:
I have a Netgear Switch (GS108) that has been running 24/7 for around 8
years.

The other week it stopped working with all the lights lit up but no activity
going through it.

On searching the web for any clues I came across 1 or 2 posts referring to
"dodgy" power supplies. So before binning the switch, I swapped the power
supply for another Netgear one.
However the original power supply was 12V and the one I was trying was only
5V. To my astonishment it worked.

So I ordered a new 12V exact replacement for the original power supply. It
arrived today but the switch is exactly the same. The lights all light up
but no activity.

I can't understand what the problem is?
The switch is marked 12V, the original power supply and replacement power
supply are both 12V but they don't operate it.
Yet the 5V power supply appears to operate it just fine.

Will I be damaging either the Switch or the 5V power supply by using them
together?
Anyone know why the 12V power supply isn't able to work it correctly even
although it is certainly able to power it?!?!

Cheers.

I had something similar happen many years ago, though with a different piece
of kit. It turned out that the power supply was just feeding 12 AC into the main
unit where it was recitifed and smoothed before being regulated down to
the supply for the electronics.
The electrolytic capacitor that did the smoothing had either dried out or
just died, so the regulator was getting full-wave rectified 12 Volts, which
by it's nature dropped to 0 Volts 100 times a second. That in turn continually
reset the electronics. Replacing the smoothing capacitor had the desired effect.

If your 5 Volt supply is providing already smoothed DC, that's probably
enough to run your router.

--
http://www.thisreallyismyhost.99k.or...4345011212.php

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember John MacLeod
saying something like:

They probably had a good deal on 12v supplies -- the 5v regulator
inside would cost only a few pence, whereas they could save a lot by
ordering tens of thousands of 12v supplies rather than a more limited
number of 12v and 5v and who knows what else in between. Makes sense
to standardise on the highest voltage required by any of the line of
items which might require a smallish power supply.

That happened with a PC radio receiver I bought years ago. The supplied
wall wart put out regulated 18V, but it turned out the receiver was much
happier with a regulated 12V (hardly surprising, as it was designed to
run off a car supply for portable use with a lappy). On 12V it's much
cooler, as the internal regulator isn't doing much work.

Steven Campbell wrote:
I have a Netgear Switch (GS108) that has been running 24/7 for around
8 years.

The other week it stopped working with all the lights lit up but no
activity going through it.

On searching the web for any clues I came across 1 or 2 posts
referring to "dodgy" power supplies. So before binning the switch, I
swapped the power supply for another Netgear one.
However the original power supply was 12V and the one I was trying
was only 5V. To my astonishment it worked.

So I ordered a new 12V exact replacement for the original power
supply. It arrived today but the switch is exactly the same. The
lights all light up but no activity.

I can't understand what the problem is?
The switch is marked 12V, the original power supply and replacement
power supply are both 12V but they don't operate it.
Yet the 5V power supply appears to operate it just fine.

Will I be damaging either the Switch or the 5V power supply by using
them together?
Anyone know why the 12V power supply isn't able to work it correctly
even although it is certainly able to power it?!?!

Cheers.

Not sure but I have a 12v router that I can't find the power lead for.
In my shed was a 9v charger from something that had long been got rid of,
which had the same shaped jack, so i plugged it in and hey-presto, it works!
As an experiment, I unplugged my cable modem (also 12v) and swapped that
into the router and used the 9v charger on the modem and that too worked
just fine.
On a related note, I bought an old radio (for work) from a carboot sale a
few years ago, no power lead, battery only. - the battery was an old
fashioned 9v jobby, not the pp3 type but the big square chappies,
pp7's....when it eventually ran out of steam, I didn't bother buying a new
one as it would have cost me more than the radio, so I used a 7.2v nokia
charger and wired it into the battery terminals, that was 3 years ago and it
still works perfect

--
Phil L
RSRL Tipster Of The Year 2008

In article ,
"Steven Campbell" writes:

Ah right, that makes sense if I've got this right?
12V is being supplied but it gets changed to 5V inside the Switch?
The regulator isn't working correctly so hence why the 12V power supplies
don't operate it.
Makes you wonder why they needed a 5V regulator inside and they couldn't
just supply a 5V power supply.

Folks who design the switch generally can't relay on a specific
power supply, as it will be supplied with a different one in
every country. In the US, they usually come with a very small
SMPSU built in the plug. In the UK, they come with a sodding
great unregulated wall-wart. If you want reliable operation
in the face of such variables, not to mention people also
changing the supplied PSU, you need to design your own PSU.
Point-of-use SMPSUs are often the norm throughout larger
commercial PC's (such as 4 and 8 socket systems), where the
main PSU generates 48V, and tiny SMPSUs transform this down
to levels from 1 to 5V for specific components, including the
CPU. This resulted in high volumes, lowering cost, size, and
excellent reliability, with the introduction of megahertz
switcher moduless. You'll find these inside standard PC's now
too, to generate the low CPU and memory voltages.

The other common failure with small netgear switches which get
moved around is that the power connector often breaks free of
the circuit board.

I wonder if that is why all the recent GS108's come with a 7V power supply!

When I first bought the small 5 and 8 port switches (and WiFi
access points), many of them ran from 5V or 12V, and I would
power them from a spare disk drive connector. It's got quite
hard to find 5 or 12V powered ones nowadays.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

"Steven Campbell" wrote in message
o.uk...
I have a Netgear Switch (GS108) that has been running 24/7 for around 8
years.

The other week it stopped working with all the lights lit up but no
activity going through it.

On searching the web for any clues I came across 1 or 2 posts referring to
"dodgy" power supplies. So before binning the switch, I swapped the power
supply for another Netgear one.
However the original power supply was 12V and the one I was trying was
only 5V. To my astonishment it worked.


Thanks all for the valuable information. It certainly helps explain what is
wrong.
I'll try and get myself a 7V supply.

cheers