How traffic signals work (1937)

[supersuds]

This is a fun, short (9 minute) promotional film made by Chevrolet in 1937 about modern traffic signaling. Traffic lights hadn't been standardized, and there are pictures of two-, three-, and even four-light systems, as well as the ones with semaphores and even pointers and rotating faces rather like a clock!

It seems to have been normal then for the yellow light to come on before the red as well as before the green. I think this is still done in England, but I haven't seen it in the U.S.

 

[washman]

I dig these old films

There's tons of them on youtube, including the classic Signal 30.

Another neat-o one is "a date with your family"

A rather dark, almost film noir is "Habit Patterns", a fav of mine.

 

[frigilux]

Same here; I love these old educational films. There are, as Ben pointed out, many of them on YouTube.

I hadn't seen this particular one, so thanks for sharing it, John.

 

[circlew]

Interesting film. Some drivers today need to watch this - I don't know how many times a day I see cars race away when the light turns green, only to have to stop at the next light that has turned red! I try to keep at the correct speed so as not to have stop at lights that are sequenced.

I liked all the colored cars in the animated part; they remind me of toy cars I had when I was a little kid.

 

[ea56]

I’ve seen this film before on You Tube. I really enjoy all of these old Jam Handy informational films. They are a real window to history. One thing I noticed was that there were no lines to designate the lanes where there were two or three lanes of moving traffic. I don’t recall ever seeing this anywhere before, even in the early 50’s when I was a kid. Can you even begin to imagine the pandemonium this would cause with todays aggressive drivers! Holy Mackerel, it would be a hot mess!

Eddie

 

[circlew]

Travel with Gale Storm

& her family in their '54 Chevrolet. I was surprised to see that Chevy had power adjusting seats by then. My Aunt Doris had a '54 Bel Air in green and white.

I'm pretty sure the closing scene was filmed on US 66 in the Cajon Pass, CA area.

 

[ea56]

It surprises me that Gale Storm did a commercial film for Chevrolet at this time, as one of her show, “My Little Margie’s” sponsers was Ford I believe. But that may have been in 1955, after this Chevy film was made. In one of the episodes that I recall she was trying to get her father, Vern, played by Charles Farrell to buy her a new 55’ Thunderbird.

Watching this film also reminded me of the family car trips my family used to take around this time. There sure was a lot more room in those cars from the 50’s.

And another thing I remember, is that my Dad always tied a Desert Bag to the front bumper, in case the car were to ever overheat in a remote area where there was no water. A Desert Bag was made out of burlap and canvas, with a screw top. You filled it with water and the wind hitting it while driving helped to keep the water cool.

Eddie[this post was last edited: 9/1/2018-20:39]

 

[wayupnorth]

I wish all traffic signals had sensors in the road to know when a vehicle is trying to get out of a busy street. Around here, they are all on a sequence that every emergency vehicle screws up and its stop, etc and then green into an empty parking lot. They swapped ours over to LED and everytime it snows you have no idea who has the right of way as they wont melt.

 

[supersuds]

According to this 1941 Chevrolet film (featuring a fairly rare 1942 Chevy), they did have sensors in the road even back then. Quite a complicated control box, all mechanical, of course, which is probably why they weren't very common!



Although much of the video is about marionettes and the notorious Chevy vacuum gearshift.

 

[speedqueen]

That "magic-box" uses a rudimentary form of computer based on relay logic. If you think this is complicated, even into the 1990s much of the long-distance telephone switching here in the US was done by Western Electric #4A toll crossbar eXchanges, these machines used relay logic and devices called card translators to figure out how to route the call based on trunk availability, eXchange rank, and destination, even just setting up the route through the internal crossbar network was a complicated act. Then with more relays, it had to store and send forward the called number so the next office down the line could do the same.

 

 

[firedome]

that was fun to watch!

As a small time signal collector, in all the signals we've restored we've used small IC-run controllers mounted inside the signal, though some collectors do rehab & use the original mechanical-cam controllers mounted in an authentic cabinet. A major signal maker was Crouse-Hinds, made in neighboring Syracuse. Here's a couple C-H signals, one a Model DT 4-way Beacon, one a "Deco" DT 3 light 3-way signal, both now operating in our garage and basement. Also had a big C-H DT 12 light 4-way, recently sold. All 1940s vintage. It's a fun hobby.

 

[supersuds]

I thought there was a traffic light collector here! Those are very cool to see, thanks. And is that a 1970 Caprice in your garage?

Thanks for the info about the phone exchanges, Richard. They are fascinating but I've never known much about them. It used to be very noticeable when calling some exchanges out in the country how slow the connections were -- I assume they were using non-Western Electric equipment of some kind.

 

[ea56]

Re: Reply #9

When I went to work for PT&T in June of 1976, the first day of orientation they took us on a tour of the 6 story building in Santa Rosa, Calif. that housed not only the operator serivices, which I was hired to do, but also the equipment rooms that housed the switching eqiupment. The switching equipment looked just like this photo.

They showed us how a call went thru the equipment to be connected to the number dialed by the customer. And as I recall the switching equipment was pretty loud. The office I worked in handled all the calls for Sonoma Co.and most of the 707 area code. There were two other smaller toll offices further north in Fort Bragg and Eureka that also had switchboards, but we handled all the directory assistance for the 707 area code.

Eddie

 

[gusherb]

I’ve always wanted to see a crossbar switch in action, but alas I was born a bit too late to catch those. I’ve spoken to a telephone hobbyist who put together his own SxS CO out of telco CO’s taken out of service, he even had a working number to dial into at some point to hear the sounds of the switches in action, as well as various different tones and signals, very cool! I asked him about crossbar switching and he said those switches are incredibly complex, they need to be all together as one piece in order to function and they require tons of electricity just to make one single connection. Oh and not to mention they take up tons of room.

 

[speedqueen]

Eddie, was your office a #1 Crossbar Tandem or a #4A Crossbar tandem? I remember you saying it handled CAMA (Centralized Automatic Message Accounting) likely from #1 and #355A step by step offices, as well as independent, non-Bell System offices. Rural offices needed an operator at the tandem to key in their number for billing, called ONI(Operator Number Identification) as opposed to larger better equipped offices that had ANI(Automatic Number Identification).

 

John, the reason for some calls to especially rural eXchanges taking longer than urban areas comes from the fact that more intermediate long-distance offices(tandems) were required to string together the connection as well as, in rural areas, and even some urban areas like Los Angeles, were primarily used with step-by-step equipment that was directly controlled by rotary dial pulses, no relay logic, no route translation, no support for TouchTone unless a pulse converter was added. These offices could only take dial pulse on inbound trunks from other offices as well, so in many cases the last 4, 5, or 7 digits of the phone number would be rotary dialed by a toll tandem office into the last office. This could be after a longer than usual route, too.

 

Non-Western Electric equipment was generally just as fast, Northern Electric NX1 crossbar offices were comparable, step was step, no speeding up or slowing it down.

 

[ea56]

Richard, we had some direct dialed numbers that went thru the CAMA board and others that didn’t, so I’m not completely sure just what went thru the switch banks that they showed us, but I suspect they were the calls that by passed CAMA, and were automatically connected and billed. But, then again, the calls that went thru CAMA would have also needed to go thru the switching equipment too, but probably only to the point that they reached the CAMA operator, who keyed in the callers number for billing the call. Shortly after I left the company in late 1978, all the calls were direct dialed and by passed both CAMA and the cord board, I think this was around 1980.

When I worked in the toll office we connected all the coin phone calls, collect, person to person, overseas, mobile and marine, and hotel/motel calls, as well as the County Jail. It was quite and interesting job, and you really needed to be on your toes!

Eddie

 

[speedqueen]

Thanks Eddie, I appreciate you sharing your little snippet of history, I was born in the wrong era to be interested in any of this sadly, so every little bit of information helps me learn more, since I cannot experience it directly.

 

[firedome]

the Caprice...

is a 1968 4 door hardtop (aka Sport Sedan).

 

[iej]

@speedqueen - Crossbar

Interestingly enough, the most local versions of crossbar switches (certainly the later ones that were built in the 1970s and were somewhat computerised) were still in use as late as the 1990s in quite a lot of places, living side by side with digital switching.

The last step-by-step switch (older tech again) was removed from the US network in 1999, a small community dial office and another small one in Nantes, Quebec was only cut over to a digital Nortel DMS 10 on June 14, 2002.

The last one in the UK was in service until 1995 replaced by GPT/Marconi System X digital switching.

I know the last semi-computerised Ericsson ARE crossbar local exchange here in Ireland was cut over to Ericsson AXE 810 in 1999. Those old 'ARE' switches used the matrix from an Ericsson ARF crossbar, modernised with digital registers and managed by a digital 'parent'.

I know in Europe our crossbars were mostly Ericsson AR series or ITT Pentaconta.

Ericsson had a whole series of ARF (large local), ARK (mini local/rural), ARM (transit / international) which were used all over Europe and in places like Australia quite extensively. All Canadian international transit traffic was going through a pair of Ericsson ARM switches for many years too.

There were more advanced Ericsson AKE "Code Switches" and ITT Metaconta which were both using miniaturised crossbar matrixes with aspects of computer control. They were around for a while in the 1970s / 80s but were utterly dead end technology, as digital switching became the norm.

Ericsson ARF:



Technology marches on, but it's sad to see the old ARF ending up in a dumpster. Something very 'real' about all those clicking relays.