J
Jeff Liebermann
Guest
On Thu, 15 Aug 2013 11:47:07 -0700, Don Y <this@isnotme.com> wrote:
It's kinda tricky to energize a relay AFTER the power is lost. I
suppose I could charge a cazapitor and dump the charge into a latching
relay release coil if the power is lost. The only problem is that I
get only one chance to change the latching relay state.
Well, the average packaged relay burns about 350 mw in the coil. At
$0.17/kw-hr, that's 3 kw-hr per year or about $0.52 added to your
electric bill every year. I suspect the ecological damage caused by
the manufacture of the components needed for a more sophisticated
device substantially exceed this cost.
><http://www.ericofon.com/catalog/classic3/images/trimline/wall/trw_green.jpg>
<http://www.ericofon.com/catalog/classic3/trimline.htm>
I have one of the WE desk phone versions. As I recall, the coil cord
on the WE version had a very large vinyl molded connector on the phone
end, and direct wired spade lugs on the handset. Are you sure yours
has a normal handset RJ22 modular jack?
If nobody sees the phone, why do you care about the color of the coil
cord? Again, I live in earthquake country. When he had our last big
shake in 1989, all the phones fell off their hangers and went offhook.
Nobody ever tested the software in the switch for such a massive off
hook condition. Of course, that triggered a bug which caused the
switch to continuously reboot. No phone service for several days
until the bug was fixed in the switch or billing machine (I forgot
which). Since then, all unattended phones get an elastic strap to
hold the phone in place in the event of an earthquake.
We do it better. I live in a forest. Most of our telco plant is
aerial (on poles). When the wind blows, the trees fall, breaking the
lines. It's not unusual to see 3 adjacent splice boxes on along the
cable. Also, lots of broken pairs.
>Uncle used to run a CO.
I used to work in a battery room in the 1960's.
Times have changed. A more recent tour:
<http://www.wap.org/journal/cotour/>
I have some photos of the local CO, but I had to promise not to
distribute them. Basically, it's a museum. Lots of ancient hardware
just occupying space. Plenty of Strowger switches and crossbar racks,
some of which were powered on. When I asked what they were doing, I
was told "depreciating".
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
Ummm... I think it's called a relay. Connect the solenoid to
something that monitors AC power, such as a common wall wart. The
contacts switch the POTS phone from the ATA when energized, to the
POTS line when the power drops.
Too trivial a control algorithm. You need to be able to "drop"
(in your example) the relay even when power is available (if
you sense something else has compromised the internal phone service).
It's kinda tricky to energize a relay AFTER the power is lost. I
suppose I could charge a cazapitor and dump the charge into a latching
relay release coil if the power is lost. The only problem is that I
get only one chance to change the latching relay state.
Also, consuming electricity 24/7 to protect against something that
isn't *expected* to happen is wasteful. Smarter to use a latching
relay with a power reserve that you can "pulse" the latch/release
coil as needed.
Well, the average packaged relay burns about 350 mw in the coil. At
$0.17/kw-hr, that's 3 kw-hr per year or about $0.52 added to your
electric bill every year. I suspect the ecological damage caused by
the manufacture of the components needed for a more sophisticated
device substantially exceed this cost.
><http://www.ericofon.com/catalog/classic3/images/trimline/wall/trw_green.jpg>
<http://www.ericofon.com/catalog/classic3/trimline.htm>
I have one of the WE desk phone versions. As I recall, the coil cord
on the WE version had a very large vinyl molded connector on the phone
end, and direct wired spade lugs on the handset. Are you sure yours
has a normal handset RJ22 modular jack?
Phone has to reside *in* a closet (I don't want to "see"
any phones in the house!) and only accessed in times of
service outages, etc.
If nobody sees the phone, why do you care about the color of the coil
cord? Again, I live in earthquake country. When he had our last big
shake in 1989, all the phones fell off their hangers and went offhook.
Nobody ever tested the software in the switch for such a massive off
hook condition. Of course, that triggered a bug which caused the
switch to continuously reboot. No phone service for several days
until the bug was fixed in the switch or billing machine (I forgot
which). Since then, all unattended phones get an elastic strap to
hold the phone in place in the event of an earthquake.
Seeing individual feeds to residences ON TOP of the soil
(for months or years -- permanent tempporary fix!) is
not uncommon. And you want to rely on this for *what*??
We do it better. I live in a forest. Most of our telco plant is
aerial (on poles). When the wind blows, the trees fall, breaking the
lines. It's not unusual to see 3 adjacent splice boxes on along the
cable. Also, lots of broken pairs.
>Uncle used to run a CO.
I used to work in a battery room in the 1960's.
Three memorable things from a private
tour he gave me as a kid:
Times have changed. A more recent tour:
<http://www.wap.org/journal/cotour/>
I have some photos of the local CO, but I had to promise not to
distribute them. Basically, it's a museum. Lots of ancient hardware
just occupying space. Plenty of Strowger switches and crossbar racks,
some of which were powered on. When I asked what they were doing, I
was told "depreciating".
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558