D
Don Y
Hi Jeff,
Lots of ways to energize a relay after loss of (primary) power!
You just need *secondary* power -- whether from a big cap or
a "backup battery" that is busy trying to keep your VoIP
gateway running during a short? power outage (and, just before
it realizes it can't keep itself UP any longer, throws the
relay before shutting down)
Again, if you've already got the electronics there doing other things,
what is the cost of a few hundred bytes of ROM? (for the algorithm)
You've already assumed the cost of the *relay*...
Positive. The cord is on the desk here -- sans handset and base!
Nobody sees the color of the carpet in the trunk of my car, either.
Why didn't the manufacturer opt to put whatever he had lying around
in the shop in there when he built the vehicle? I'm sure he could
have saved a few pennies...
I also like all my tires "mounted white" or "mounted black" -- not
some convenient mixture of the two. :>
Yup. That's how things are back East. All the utilities hang.
And, each time a drunk buys a telephone pole, someone loses
something for some period of time...
OK. I recall seeing banks of batteries. And some sort of
*motor* in continuous motion (I think something to do with ring?)
I would *hope* so! It's been >40 years since I was there! :>
Ha! Yet, probably, still fully functional!
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.
Lots of ways to energize a relay after loss of (primary) power!
You just need *secondary* power -- whether from a big cap or
a "backup battery" that is busy trying to keep your VoIP
gateway running during a short? power outage (and, just before
it realizes it can't keep itself UP any longer, throws the
relay before shutting down)
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.
Again, if you've already got the electronics there doing other things,
what is the cost of a few hundred bytes of ROM? (for the algorithm)
You've already assumed the cost of the *relay*...
<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?
Positive. The cord is on the desk here -- sans handset and base!
If nobody sees the phone, why do you care about the color of the coil
cord?
Nobody sees the color of the carpet in the trunk of my car, either.
Why didn't the manufacturer opt to put whatever he had lying around
in the shop in there when he built the vehicle? I'm sure he could
have saved a few pennies...
I also like all my tires "mounted white" or "mounted black" -- not
some convenient mixture of the two. :>
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.
Yup. That's how things are back East. All the utilities hang.
And, each time a drunk buys a telephone pole, someone loses
something for some period of time...
I used to work in a battery room in the 1960's.
OK. I recall seeing banks of batteries. And some sort of
*motor* in continuous motion (I think something to do with ring?)
Times have changed. A more recent tour:
<http://www.wap.org/journal/cotour/>
I would *hope* so! It's been >40 years since I was there! :>
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".
Ha! Yet, probably, still fully functional!