Were there ever male operators in those days?

A friend of mine was the first male operator at the Brunswick, GA exchange. He got into a lot of arguments trying to convince dialers that he was in fact an operator. A lot of people just hung up on him. This would have been in the 60's long after crank dialing was replaced with direct dialing but still had operators "on call" for handling dialing problems or making overseas calls.

 

Actually, at the very beginning in the US, they had boys doing the operator job but they were lazy and rude to the customers. By chance, they had a young woman do the job and it was so successful they never hired another male until the 70s.

AT&T created a culture of operators and very extremely strict about selection and training. This video is fascinating.

Yaakov, thanks for sharing this video. I sent the link to my children so they could learn what their grandmother did.

 

There's one of those switch buildings in my neighborhood,

They were first electro-mechanical switches which caused problems when dial-up data connections got above 1200 baud. There are actual international treaties, International Telephone Union Treaty, and US legislation that required telephone systems to meet I beleive it was 4800 baud in the 80s. Mechanical switches could not, requiring me (and others) to connect @ 1200 baud making long distance calls thus driving up the cost of data connections. We complained to the GA Public Service Commissioner who took the phone company to task over it. The phone company pulled out their contract which stipulated that the service was on a take it or leave it basis and therefore not required to meet the data regulations. Once they had solidstate switch gear installed getting a 14.4 or 28.8 kbit/sec connection on a standard home telephone lime became possible. Even higher on a more expensive data line. The old switch gear racks have been replaced by much smaller IC boards. Yes, one good thing about good old landline telephone is it is a powered system with excellent UPS backup capability. If you look around the net, you will find emergency LED lights that can be plugged into a home telephone jack to give lighting when the electrical power system is dead.

 

The number registers on the return only, and speeding it up can foul up the registration method and either record the wrong number or result in no connection.
Why the return speed is governed.
Depended on the exchange.

I repaired old military Strowger switch phone systems many moons ago.
https://www.telephonecollectors.inf...38-this-is-automatic-electric-1955-ocr-r/file

https://forum.allaboutcircuits.com/threads/first-digital-phone-call.96706/post-721078
https://forum.allaboutcircuits.com/threads/first-digital-phone-call.96706/post-721166

 

I made a living for most of a life time with these.

View attachment 263484

Little Brother still in use.

 

View attachment 263770View attachment 263771
Little Brother still in use.

In my youth I would marvel at Eimac tubes while playing with the 6L6s and 12AX7s. Even today this 1500W final is listed on Newark's site (though "unavailable").

​

 

https://spectrum.ieee.org/the-vacuum-tubes-forgotten-rival

During the 1950s, the U.S. military was using magnetic amplifiers in automatic pilots, fire-control apparatus, servo systems, radar and sonar equipment, the RIM-2 Terrier surface-to-air missile, and many other roles. One Navy training manual of 1951 explained magnetic amplifiers in detail—although with a defensive attitude about their history: “Many engineers are under the impression that the Germans invented the magnetic amplifier; actually it is an American invention. The Germans simply took our comparatively crude device, improved the efficiency and response time, reduced weight and bulk, broadened its field of application, and handed it back to us.”

Modern uses of magnetic amplifiers.
https://elnamagnetics.com/wp-conten...ics-Documents/Mag_Amp_Cores_and_Materials.pdf

Section 2.2
https://www.navsea.navy.mil/Portals/103/Documents/NNPTC/Electrical Eng/applied_ee_v1.pdf

 

How about a carbon telephone repeater used in long distance telephony before tube amps.
From Wikipedia:
Type 3A mechanical carbon repeater element, a crude early telephone repeater used in the early years of the 20th century by American Telephone and Telegraph Co. to amplify signals on long distance telephone lines. It consisted of a "speaker" and carbon microphone coupled together. The weak incoming signal was applied to a coil, which vibrated an iron plunger, creating sound vibrations, which applied varying pressure to a microphone cell containing granulated carbon, with electrodes. The varying resistance of the carbon modulated a strong current through the cell, which passed into the outgoing telephone line, producing a larger amplitude than the incoming signal. The carbon telephone repeater was invented by H. E. Shreeve of AT&T and the first successful test was in 1904 in a circuit between Amesbury, Massachusetts and Boston. The carbon repeater was very distorting and unsatisfactory, and was replaced by Audion vacuum tube repeaters, the first successful type of repeater, in 1914, making possible the first transcontinental telephone line between New York and Los Angeles in 1915.

 

I remember multi spindle screw machines in Chesterfield MO many years ago. They were still in use after century of operation even after being completely covered in water and mud due to floods. And the thing is programmable... well program is all in metal gears. Originally entire line of them was driven by a single rotating shaft with single belt connecting each machine to the driving shaft. At some point steam driven shaft was replaced by individual electric motors. Depending on program machine could do many different operations and rather fast. It could rotate part, flip it over, cut threads and various profiles. Next to them was couple of modern CNCs. It was quite remarkable thing to see in action. It was also really cool to see the drawings (blue prints).

 

One of the last machines I retro-fitted to CNC before retiring was an old '1950's Gray double-head Planer for the Canadian Pacific RR.
The shop that checked out the AC motors, mentioned they were the most well balanced motors they had seen.


Before Pic:

 

One of the last machines I retro-fitted to CNC before retiring was an old '1950's Gray double-head Planer for the Canadian Pacific RR.
The shop that checked out the AC motors, mentioned they were the most well balanced motors they had seen.


Before Pic:
View attachment 263926

I am surprised the guy in the blue hard hat is not wearing a lab coat that machine oil has to get all over the place. when you go home does the smell of machine oil penetrate your clothing?

 

Hard hat and safety boots were the only Reg in place.
Most of it was dry machining and planing , the switch-point-frog rail planers screams could be heard a block away!

 

Crystal Radios

These were some of the earliest forms of radios, they worked without any power source, back when AM was the norm. Some of them were simple, they could be made with a razor blade and a pencil lead.



What was unbelievable about them was, they produced sound just by the power of radio waves of AM radio stations, they didn't require any power source. They are no longer made, it would be difficult for many normal people and electronic engineers to think such a thing would exist.

 

We used to put them together as kids, mine had the genuine Galena crystal with the ' Cats whisker'
Army surplus headphones.

 

Crystal Radios

These were some of the earliest forms of radios, they worked without any power source, back when AM was the norm. Some of them were simple, they could be made with a razor blade and a pencil lead.

View attachment 263935

What was unbelievable about them was, they produced sound just by the power of radio waves of AM radio stations, they didn't require any power source. They are no longer made, it would be difficult for many normal people and electronic engineers to think such a thing would exist.

One of my first electronics projects. My dad let me connect to his short wave antenna that ran from the house to a tree 100’ feet away

 

short wave antenna that ran from the house to a tree 100’ feet away

We had such a wire antenna, when I was a kid, running from the house to a large Elm tree limb (so sad they're all gone now) for AM reception.
I remember it was attached to the tree with a long screen-door spring so the movement of the tree in the wind wouldn't break the wire.

 

I nominate the IBM Selectric Typewriter, which I marvelled at 45 years ago, even more so after I was trained in servicing them. An astonishing mechanical design - to produce such a smooth ergonomic link between operator input and printed output I found incredible. And then I met the Selectric Compositor - I couldn't even describe the mechanics of that - it was beyond me. And finally the 2741 Selectric Data Terminal - a Selectric typewriter with a mass of switches and solenoids wired through it to perform async comms over a telephone wire. I thought those machines stretched the possible a long way - all replaced with electronics, a few chips these days.

 

The General Radio 650 Impedance Bridge generated a 1 kHz sine wave using a "microphone hummer". Like an electric buzzer but with the contacts replaced by a carbon microphone.
http://conradhoffman.com/GR572B.htm

If anyone is into crystal radios, look for publications from "Modern Radio Labs". I built one that worked well enough to pick up WWV on shortwave from Colorado (maybe the No. 2-A). Many of the books are available here; scroll down to Elmer G. Osterhoudt MRL
https://worldradiohistory.com/BOOKSHELF-ARH/Bookshelf_Hobbyist.htm

 

NOS tubes have arrived to fix the HV power supply.


200K Ohm 600W HV dummy load (MHV connector) with PIC18 PS test board controlling voltage and current outputs.

Solid at the full test range voltage and current using the test board serial link for control.