Antique Telephone Tester

[David Simpson]

Just recently been given this wee buzzer/induction coil Tester(I assume). A pal thought it was just a wee "Electric Therapy Machine", but the manufacturers label indicates a possible testing function.
I've taken its picture alongside my Victorian Therapy apparatus(lhs) and a later Edwardian one(rhs)
The label says :- Manufactured by "The Consolidated Telephone Construction & Maintenance Co. Ltd."
Farrington Rd, London EC Size = 5.5" x 3.5" x 4" high.

Any info most appreciated.
Regards, David

[Station X]

Possibly an induction coil to generate 25Hz ringing current, or it may be an insulation tester. The lack of any form of meter probably rules out the latter suggestion.

[AC/HL]

Not directly relevant, but there is some information about the manufacturer here: https://www.vintage-radio.net/forum/...d.php?t=122398

[Graham G3ZVT]

A couple of press clippings that might be of interest.


All was not well at Consolidated at the start of the new century

[Graham G3ZVT]

David, I think this is part of a telephone, and not a testing device.
Rather than a rotory magneto to crank, you seem to have a cylindrical magnet that you pull-push to ring the bell of the other instrument.

Then again, maybe it's only for signaling, perhaps for railway use.

[greenstar]

The medical coil on the left is similar to others made by Ludwig Schulmeister. I have one myself, although mine has no manufacturer's mark.
Beautiful things.
Tony

[russell_w_b]

Originally Posted by rambo1152

David, I think this is part of a telephone, and not a testing device.
Rather than a rotory magneto to crank, you seem to have a cylindrical magnet that you pull-push to ring the bell of the other instrument.

It looks like a high-voltage induction coil to me, and the iron shaft you push into the coil will increase the inductance and consequently the magnitude of the high voltage generated.

I'm guessing a variable voltage insulation or flashover testing device, and there may have been an instruction on how far in the core is pushed to achieve a certain voltage.

Just because a telephone company manufactured it doesn't mean it was for telephone use. The Beethoven Mk:II shot-firing exploder contains an ALINCO hand-magneto as found in contemporary field and other Bakelite telephones as an example of telephone manufacturers farming out products.

[David Simpson]

Thanks Guys for all the info on the company. The adjustable tubular insert is chromed brass which shields the inner iron core. Hence the secondary's o/p voltage is adjustable. The diddy therapy apparatus on the right works on the same principal.
I've only just been given this item, & yet to carefully test it & power it up. The "Schulmeister" is in great nick. Back in the early 70's, I used to get my classes of RAF apprentices to hold hands & form a circle & it could feed about 15 of them off a 9V battery. Happy days.

Regards, David

[Graham G3ZVT]

Originally Posted by russell_w_b

Just because a telephone company manufactured it doesn't mean it was for telephone use. The Beethoven Mk:II shot-firing exploder contains an ALINCO hand-magneto as found in contemporary field and other Bakelite telephones as an example of telephone manufacturers farming out products.

Yes, I've changed my view on this now.
The product diversity of this company also embraces the low-tech.

[russell_w_b]

Might it've been the prime-mover for a small spark transmitter?

[David Simpson]

Well - it jolly well works ! Connected my DC PSU set at 4V, it drew approx. 160mA through the primary. An AVO 8 indicated approx. 30V of fundamental rough AC from the secondary. However, it scoped, using a x8 probe, about 1200V P - P spikes. The Time/Div indicated a freq. alternating between 25 & 50 Hz. This was due to the thread being pretty phooked on the spark-gap adjustment screw. A h/held freq. counter also roughly indicated similar frequencies. Inserting the chromed brass tube, thus shielding the iron core, reduces the sec. o/p to nothing.
I'm guessing this is the oldest piece of antique electronics I've ever worked on. Less than half the size of the "Schulmeister", which is of a similar age, but in pristine nick.

Regards, David

[PaulR]

Originally Posted by rambo1152

A couple of press clippings that might be of interest.

Attachment 276753 Attachment 276754
All was not well at Consolidated at the start of the new century
Attachment 276756

"House to stables, house to lodge." Must get one of each. Quite expensive at £3 for the two though!