Watching a 1959 movie (On The Beach). Is this a current source symbol?

[JoeN]

Or did it mean something else back then?  And more importantly, is there a short timeline history out there somewhere when electronic devices and certain symbols came into use or went out of use.  It would be interesting to read.  I'd even spring for a book if it was good and comprehensive.  Dave tie-in:  Movie is set down under about half the film.  For comedic effect it has several big name American actors playing Australians, poorly.  Some exteriors seem authentic though.

[krish2487]

The two circles touching is a transformer symbol, not a current source.
http://www.daenotes.com/electronics/basic-electronics/transformer
 

[HackedFridgeMagnet]

I saw some old switchgear that looked similar to that last night, at Hobart Tafe.
IIRC (it was a real quick tour) it was some some sort of variable speed motor control, that was in fact a motor driving a generator driving a motor.

There was all sorts of old stuff there, I said in a few years you'll have a museum, he replied that they already had one.

[vk6zgo]

The two circles touching is a transformer symbol, not a current source.
http://www.daenotes.com/electronics/basic-electronics/transformer
 

This link says it is an "Architectural Symbol",---it is not used  as a transformer symbol in Electronics.
The two circles were commonly used as a current source symbol for many years,( Older books on transistor theory are full of them)

[Delta]

They are transformers.  The same symbol is still used on modern HMI displays controlling switchgear and such.

[mij59]

Its a 3 phase transformer e.g. 10kV/400V 630kVA each transformer powers a powerrail in the top of the cabinet.
Both transformers are paralleled with the switch to the right of the transformer symbol

[Shock]

The labels say.. top isolated voltage transformer and btm isolated voltage transformer.

[matseng]

Thanks for the tip  - now downloading On The Beach, and Fail Safe 1964/2000 editions.

[krish2487]

Correct,
2 points.
1. A current source usually has a arrow showing the direction of current flow.
2. There is a difference between electrical and electronics symbols. In the earlier days, a transformer was represented using overlapping circles in a line or a wiring diagram. Nowadays, it is rare but the old timers use it.


A transformer is a electrical item, a current source electronics item.


Again, it is pretty evident from the year of the movie - 1959. Thats what gives it away as a transformer.


Quote from: vk6zgo on Today at 09:12:33 PM

>Quote from: krish2487 on Today at 07:48:03 PM

The two circles touching is a transformer symbol, not a current source.
>http://www.daenotes.com/electronics/basic-electronics/transformer
 

This link says it is an "Architectural Symbol",---it is not used  as a transformer symbol in Electronics.
The two circles were commonly used as a current source symbol for many years,( Older books on transistor theory are full of them)