Telstra hushing up cable risk say installers

I had my Modem replaced today after damage the "Telstra Contractor" said was
caused by a lighting strike some distance away on the telstra cable. A
little research and this was found. Beware of surges through the Telstra
Broadband cable.

Boxer



Telstra has done nothing to protect cable customers' computers against the
risk of huge power surges coming down Telstra's Foxtel cable, according to
cable installers.

Whirlpool first reported the risk two months ago, when a cable contractor
came forward to warn the broadband community that the isolators that Telstra
installs in the grey box at the front of premises weren't doing their job
properly, and that customers' computers were being damaged.

Another installer has contacted Whirlpool to report that Telstra has still
not done anything to protect customer's premises. He writes:

I am a Telstra contractor installing Bigpond Broadband in the Brisbane area.
We have had a lot of storms here and over the Christmas period I was doing
service calls. I replaced modems, network cards and isolators, sometimes all
three on some jobs; depending on how close to the customer the lighting
entered the network.

Customers could not understand how it could damage their equipment
(including motherboards and whole computers in some cases) when power cords
were unplugged.

The answer is quite simple: the isolators only protect the network, not the
customers' premises. The isolator stops the power surge coming back down the
cable into the network.

We have to purchase these particular isolators and have not been informed of
any change [by Telstra management] for the future.

The cable installer, who asked not to be named for fear of repercussions
from Telstra, warned users that the only way to protect their systems during
a storm was to unscrew the Foxtel cable from the wall plate, thereby fully
disconnecting the computer from the Foxtel cable.

 

I'm not sure on their current stance on this, but a couple of years ago
the Telstra terms and conditions specifically stated that you were not
to actually unplug your cable modem / settop box from the wall outlets.
Reason being that the signal on your local cable segment is amplified a
certain amount, based on the number of units connected to that segment.
This amplification is a manual configuration on the cable demux unit,
it can be done remotely, but it's not an automatic adjustment -
someone's actually got to change it.

Disconnecting a unit raises the power available to remaining units on
the segment, and over a certain threeshold, the remaining units won't
sync up. Opposite problem with adding extra units - we went though
three months of hell before they increased the amplicifaction on our
segment, which cured a lot of our random sync problems. The reason they
finally gave was that they had had a promotional drive, and a lot of
people had signed up, but no-one had actually done the maths.

So I wouldn't go disconnecting the cables. Feel free to do it youself,
but I wouldn't.

There was a bit kerfuffle about the whole lightning strike thing last
Christmas time here in Bris. We had a couple of good electrical storms.
I had a surprisingly competent cable tech out home on an entirely
unrelated problem. He was telling me that he had been busy replacing
entire street's worth of blown cable modems. A Lot of customers were
out of contract, therefore had to cough up the $500 for a replacement
modem if they wanted to continue their service. Not many were happy
about that, he indicated!

The only thing I've found that may be of any use is these :
http://www.ozcableguy.com/#surge
(or
http://www.oztechnologies.com/search.asp?Brand=&Words=F9G723au3M-F-GY&SUBMIT=+Search
or
http://tinyurl.com/c688f)

I haven't actually got around to buying one myself, but have been
meaning to since the aforementioned last Christmas. I have bought other
stuff from the OzCableGuy, and can vouch for prompt, professional
service. And no, I'm not the OzCableGuy.

Cheers!
Matto
05 Sprint ST

 

what a life!

 

Belkin sell a combo a/v connector and power board with surge protection,
plug your tv antenna, phone and cable connection into it, and then into
their normal inputs to have surge protection

JL
(disclaimer- only saw a 3 line ad on it yesterday, haven't investigated)

 

I had a look at one today and may buy one in the near future ($285) however
I found some in line surge protectors from Dick Smith at $19.00 each
(recommended by the Telstra Installer) for the cable internet and Foxtell
that I installed today to give me some protection. I use a UPS for my
computers and printers and fax so that should help.

Boxer

 

Not long after my ISDN modem was installed and having multiple drop-out
problems Telstra sent a Tech out to my place. Scruffy looking guy in a
Hilux. Said his name was Jed Clampett and I tried to keep a straight face.
He called some idiot and told him to upgrade the Telstra software in my area
so that it matched mine. Fixed the problem.

Theo

 

Be wary of cheap surge protectors. They generally have a couple of
capacitors that blow apart at the first decent surge leaving you with the
impression that it is still working. An actual effective surge protector
costs closer to $100.

Theo

 

bloody telstra apologists! of course it's a coverup, this is the internet!

 

wash your mouth out. i'd rather pay a bit less for something that
doesn't work than pay a bit more for something that does.

cheap rules!

 

To sell ineffective products, some surge protector
manufacturers encourage you to assume "surge protector = surge
protection". Those are two completely different components of
a surge protection 'system'. One component that all
protection 'system' require is the surge protection - also
called earth ground. That Belkin has no earth ground. No
earth ground means no effective protection. So Belkin also
hopes you never learn about that one essential component -
single point earth ground.

What does a protector do? Connect an incoming transient to
earth ground. After all, destructive transients are the
electricity that seeks earth ground. If you don't earth the
incoming transient, then that incoming transient will find
destructive paths to earth via household electronics.

Cable needs no protector. It should be connected less than
3 meters to a single point earthing before that cable wire
enters the building. What does a surge protector do? Makes a
temporary connection to earth. But cable shield can be
earthed constantly. Therefore no protector required.

Phone lines cannot be earthed constantly. So we do same
earthing - except we put a protector in that earthing
connection. The protector is nothing more than a temporary
wire. The protector - as stated up top - is not protection.
But if the protector does not have a less than 3 meter
connection to earth, then the protector does nothing
effective.

Further details were provided in the newsgroup
aus.audio-visual.home-cinema entitled "Lightning and surge
protection?" on 3 and 5 Aug 2005 or at:
http://tinyurl.com/ayvdz

Your post assumes a protector will somehow stop or block
destructive transients. How will a cable protector do that?
How will it block the RF transient and yet let the RF signals
pass? Protectors don't know the difference between
destructive transient and signals. It does not even claim to
stop or block surges. It does claim to cost you big bucks.
It does avoid all discussion about earthing. All this when
effective cable protection requires a $2 ground block, short
wire to earth, and maybe rerouting the incoming cable where it
should have first been installed - adjacent to all other
incoming utilities and connected to the same single point
earth ground.

 

Sounds like you know what you are talking about.

Boxer

 

And industry benchmark in this stuff is Polyphaser. Their
application notes are considered legendary. What do they
discuss - their products? No. They discuss earthing
extensively at
http://www.polyphaser.com/ppc_ptd_home.aspx

If interested, days worth of reading from numerous other
sources are listed in alt.comp.periphs.mainboard.asus on 30
Mar 2005 entitled "UPS unit needed for the P4C800E-Deluxe" at
http://makeashorterlink.com/?X61C23DCA