Re: [Telecom] The crystal clear quality of a Long Distance Telephone Call
- From: hancock4@xxxxxxxxxxxx
- Date: Thu, 10 Jan 2008 18:02:24 -0500 (EST)
On Jan 9, 10:18 pm, jida...@xxxxxxxxxxx wrote:
***** Moderator's Note *****
The Bell Labs/Bellcore standard for voice circuits used to specify
response up to 4 KHz for toll circuits. That standard was enforced
throughout the Bell System, both in the design of toll equipment such
as L carrier and T carrier, and also in the design of intruments such
as the 500 set
The Bell System histories quietly point out that during WW II they
lowered the bandwidth to squeeze more channels on scarce toll lines.
I think it became 3 Hz or maybe 2.5 Hz. After the war there was such
a high demand for service they continued this for a while. How long I
don't know. This is one thing the Bell System didn't brag about. I
would imagine having a critical business conversation over long
distance during the war would not have been easy.
IMHO, a landline long distance call sounds better today than it did
say 20 years ago. While connections 20 years ago were quite good,
there was still some slight background noise and it made it clear you
were on a toll call. Today it sounds really good.
One limiting factor today is station equipment. A good corded phone
is superior to cordless phones. Further, many cordless users stray
too far from the base station or near interference and degrade the
signal. Seems like most residences use cordless phones today.
They came out with a replacement handset for the widespread 500 set
"G" model ("K"?) which does sound better. (My 20 year old Panasonic
phone has excellent sound quality.) But as long as a 500/2500 set is
in good condition it will offer very good sound. Even a 300 set with
"F" components sounds good (though admittedly the modules in my 302
set date from 1950, perhaps 1940 modules wouldn't sound as good.)
I've used pre-1938 phones (candlestick and 202 set) and they don't
sound very well. They function, you can get a message across, but not
all that great. Note that the "F" modules were retrofitted to sticks
and 202s.
. The Bell System standard was, effectively, universal,
simply because the telephone business gernerated such huge profits
that managers weren't looking for economies. The public expectation
for telephone service remained unchanged until the breakup of the Bell
System.
The Bell System never generated huge "profits". It only made a modest
return on its investment. Be assured that over the years management
most certainly did look for economies. If a new product proved too
expensive to manufacture or service it was not offered. Manual was
converted to dial when, and only when, the economics of dial--in that
particular exchange--made dial preferable.
It wasn't until well after WW II that the idea of universal service
for all truly took hold. The Bell System sought universal service and
low prices, but there was a limit to how low they were willing to go.
Before say 1955, telephone service, even message rate 4-party line,
was simply too expensive for many people to afford. By 1955 wages had
climbed enough and telephone rates stabilized that the vast majority
of people could afford a phone. Long Distance was a luxury only for
the wealthy until about 1963 for similar reasons. People made do with
letters. Until about 1971 long distance was still something most
people used sparingly at home. Around 1971 they introduced late night
DDD discounts.
The big difference was that the first priority was service, not
profits. Engineering, not marketing, was the focal point.
After divesture marketing became supreme, engineering secondary.
It was, however, the widespread adoption of cellular service that
changed user's expectations forever. The change wasn't made for
business reasons, but for physical ones: with battery life of AMPS
phones severely limited, digital standards and instruments were
designed to maximize battery life at the expense of fidelity.
Ironically, today I used my cell phone for a personal business call.
There was nasty echo on the line and I had trouble dealing with the
other person. My prior analog phone had much better quality. My cell
phone is a nice convenience, but I don't like it very much. If they
weren't pulling the plug on analog, I'd still use that.
I don't understand how swarms of people just have their cell phone
_literally_ attached to their ears. I don't like the idea of talking
in public where outside noise is a distraction and others can hear
your conversation. I miss the old oak phone booths with the little
chair and table, light and fan.
.
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