Using an AC-to-AC wall wart transformer/adapter in reverse

[Sylvia Else]

Personally I think it's 100 % A1.

Those who can't be bothered to learn never will. Sylvia is a classic example of the
crud being turned out by Universtities today. I have this awful feeling she muct have a
Batchelor's degree.

Nup. Not even that. At least, not in electronics.

Sylvia.

 

[Spehro Pefhany]

Personally I think it's 100 % A1.

Those who can't be bothered to learn never will. Sylvia is a classic example of the
crud being turned out by Universtities today. I have this awful feeling she muct have a
Batchelor's degree.

^^^^^^^^^^

What's that, a degree conferred in large groups?



Best regards,
Spehro Pefhany

 

[Phil Allison]

"Spehro Pefhany"
Eeyore

I have this awful feeling she must have a
^^^^^^^^^^

What's that, a degree conferred in large groups?

** Well, they are - aren't they ?





..... Phil

 

[Spehro Pefhany]

"Spehro Pefhany"
Eeyore



** Well, they are - aren't they ?

.... Phil

True enough. Okay, maybe it's conferred in this town, south of Darwin:

http://www.travelmate.com.au/Places/Places.asp?TownName=Batchelor_\_NT





Best regards,
Spehro Pefhany

 

[JosephKK]

When it's loosely coupled. A good example is the wall wart Ma Bell used
to give ^H^rent you to light up your Princess phone. Open circuit was say
15 volts, but with one phone's lamps, it was 8, etc. Point was, it was
short circuit proof; it could run into same and never get hot.

I still have a Princess phone. There never was a wall wart for it.
They are exchange powered. Maybe you had a vastly different model
that looked the same.

 

[Phil Allison]

"John Fields"
Sillier than Anyone Else

** The link is for a nominal 6 volt DC output wall wart that delivers 10
volts off load.

Other factors makes the regulation much poorer than a simple transformer.




...... Phil

 

[Phil Allison]

"John Fields"

Here's one that's just a transformer with better specs: 16V -> 12V NL-FL

http://204.202.11.159/tamuracorp/clientuploads/pdfs/engineeringdocs/212AS12012.pdf

** Crikey - a 1.5VA AC output wall wart.

Bout the smallest you will see.



....... Phil

 

[JosephKK]

IIRC, the original Princess had incandescent lighting for the dial.
The phone would work fine (without lighting up) on an ordinary phone
line, but did require the wall wart for the dial to light. There
was apparently a low-level "night-light" glow when the phone was
on-hook... and this *had* to come from a wart rather than from the
exchange, as phones aren't permitted to draw more than a tiny amount
of current from the line when on-hook.

I believe I recall that the wall wart was designed with a mounting
ring, through which you could fasten the wall-outlet-plate screw, so
that the wart was secured into the outlete and could not come
loose.... >search<...

Yup: http://www.ericofon.com/catalog/parts/princess/led.htm has a
photo of the Western Electric 2012 transformer used with this phone,
as well as mention of a direct drop-in LED replacement for the
original incandescent wedge-base bulb.

I believe that the dials and button panels on the Trimline phones
(sometimes confused with the Princess line) had lights which were
exchange-powered and only worked when the phone was off-hook. It's
possible that some Princess phones worked that way but I can't confirm
it.

Ah, mine must be near end of production and came with an different
(LED?) lamp. I bought it just as everybody started making telephones.
Or perhaps i completely misremembered and it is a Trimline. Won't
know until i dig it up.

 

[Matt]

With that label and measurement it does sound like a transformer. What
does the output waveform look like?

What does an oscilloscope look like?

 

[JosephKK]

What does an oscilloscope look like?

There is quite a bit of variation, it could very well look like a
computer with a sound card.