Misc. Restoring a Butler's Indicator Box

  • Thread starter Thread starter Steve4Physics
  • Start date Start date
Click For Summary
SUMMARY

The discussion focuses on the restoration of a butler's indicator box, specifically addressing the functionality of two coils per indicator and the purpose of a push-button. Each indicator utilizes one coil to set a magnetic flag when a remote button is pressed, while the second coil clears all flags when the local button is activated. The panel operates on low voltage DC, typically requiring a battery between 2 and 6 volts, with polarity being crucial for the correct operation of the clear button. Historical context is provided regarding Julius Sax & Co, the original manufacturer, which ceased operations in 1920.

PREREQUISITES
  • Understanding of electromagnetic principles, specifically coil functionality.
  • Familiarity with low voltage DC circuits and battery connections.
  • Knowledge of magnetic polarity and its effects on electromagnetic devices.
  • Basic skills in electrical restoration techniques.
NEXT STEPS
  • Research the principles of electromagnetic coils and their applications in signaling devices.
  • Learn about low voltage DC circuit design and troubleshooting methods.
  • Study the history and technology of domestic telegraph instruments, particularly those made by Julius Sax.
  • Explore restoration techniques for vintage electrical devices, focusing on safety and functionality.
USEFUL FOR

Electronics enthusiasts, restoration hobbyists, historians of technology, and anyone interested in vintage electrical signaling devices will benefit from this discussion.

Steve4Physics
Homework Helper
Gold Member
2024 Award
Messages
2,797
Reaction score
2,512
TL;DR
Understanding some unusual wiring in a butler's indicator box.
Hi. I’m hoping to restore a reclaimed butler’s indicator box – see photo’:
1737580480434.jpeg


I’ve done a smaller one before and it was electrically trivial – a single coil for each indicator.

But in this one, each indicator is activated by two (differently sized) coils. And on the side of the case there is a push-button, the purpose of which is unknown. See photo’s:


1737580596314.jpeg

1737581563291.jpeg


Does anyone know, or can suggest, why there are 2 coils per indicator and the purpose of the push-button?

Thanks.

(Edit: I would usually get my butler to sort out this sort of thing but they are on holiday.)
 
Last edited:
Physics news on Phys.org
Steve4Physics said:
Does anyone know, or can suggest, why there are 2 coils per indicator and the purpose of the push-button?
One coil sets a magnetic flag when a remote button is pressed, the other clears all the flags when the local button is pressed. You will need to identify the magnetic poles of the horseshoe shaped magnets, by using a small magnetic compass, or a sense magnet. Attraction or repulsion polarity changes the state, with the state being remembered by the changed position of the horseshoe and its field.
 
  • Informative
Likes Steve4Physics
Baluncore said:
One coil sets a magnetic flag when a remote button is pressed, the other clears all the flags when the local button is pressed. You will need to identify the magnetic poles of the horseshoe shaped magnets, by using a small magnetic compass, or a sense magnet. Attraction or repulsion polarity changes the state, with the state being remembered by the changed position of the horseshoe and its field.
Thank you @Baluncore. That makes sense. I hope the values of current needed to make it work properly aren’t too critical - some trial-and-error will be called for.
 
The panel is low voltage DC. I would expect a battery of between 2 and 6 volts would be used. The battery would connect to two terminals in the box. Polarity is important since the clear button must clear, not set, all flags.

I believe there may have been an external bell, or a buzzer, to momentarily attract attention to the indicator board. For such an early design, it may have been in series with the battery.

Advertisement for the indicator.
https://www.gracesguide.co.uk/File:Julius_Sax_and_Co_1922BM.jpg

https://distantwriting.co.uk/appendices.html
"Julius Sax, 108 Great Russell Street, Bloomsbury, London; Domestic telegraph instrument maker. Sax, born in 1825, emigrated from Sagarre (sic), Russia, to London in 1851 after apprenticeship as an optical instrument maker and working for Siemens & Halske in Berlin. He established his own philosophical instrument firm in 1855. Sax had workshops in several parts of London until, in 1864, he took premises at 108 Great Russell Street, where his firm remained for a half-century. He is best known for his domestic electric telegraph instruments, bells and alarms for houses, hotels and offices. His first domestic telegraph was introduced in 1864 and he patented several varieties of electric bell. Sax’s bells were widely used in the head offices of banks and insurance companies in London from the mid-1860s but he did not provide messaging telegraph instruments in any quantity. Sax, a supplier to Michael Faraday, also made more substantial optical and electrical instruments, latterly manufacturing telephones as well as electric bells. He married in 1863 and had four children. After his death in August 1890 Julius Sax & Company became a joint-stock concern in 1892."

https://docs.neu.edu.tr/library/4824543535.pdf
NEAR EAST UNIVERSITY. Lefkosa (Nicosia, Cyprus) - 2004
Faculty of Engineering. Department of Electrical and Electronic Engineering. ELECTRICAL INSTALLATION. Graduation Project EE- 400
Student: Umut Caglar Camoglu. Supervisor: Dr. Kadri Buruncuk.
Page 5.
"Julius Sax began to make electric bells in 1855, and later supplied the telephone with which Queen Victoria spoke between Osborne, in the Isle of Wight, and Southampton in 1878. He founded one of the earliest purely electric manufacturing firms, which exists today and still makes bells and signaling equipment."

That was written in 2004 ... So where is that firm today?
 
  • Informative
  • Love
Likes Steve4Physics and hutchphd
Baluncore said:
The panel is low voltage DC. I would expect a battery of between 2 and 6 volts would be used. The battery would connect to two terminals in the box. Polarity is important since the clear button must clear, not set, all flags.
.
... So where is that firm today?
Wow! Thank you for all that.

Inspired by your research, I found, on the UK government national archives site, that Julius Sax & Co Ltd seems to have been wound-up in 1920.

There is an entry in the “Supreme Court of Judicature: High Court of Justice, Companies Court: Companies (Winding-up) Proceedings”. https://discovery.nationalarchives.gov.uk/details/r/C5051546
(The term ‘& Reduced’ here apparently means ‘Wound Up’, i.e. legally dissolved.)

Incidentally, if ever you need an instrument for obtaining the correction of lunar distances from the Sun, Julius Sax also made them: https://collection.sciencemuseumgro...he-correction-of-lunar-distances-from-the-sun
 
Hey folks! So I’m kinda losing my mind over my hedgie’s setup lately. No matter what I do, the enclosure keeps getting super humid and it’s starting to smell funky. I clean it, switch bedding, crack the window, the whole nine yards… but it still ends up damp and I’m worried it’s gonna mess with my little dude’s health. I’m starting to feel like I’m doing something wrong even though I’m trying so hard. Has anyone dealt with this before? Any tips, hacks, gear recs… literally anything would...

Similar threads

  • · Replies 19 ·
Replies
19
Views
2K
  • · Replies 9 ·
Replies
9
Views
3K
  • · Replies 10 ·
Replies
10
Views
3K
  • · Replies 17 ·
Replies
17
Views
9K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 18 ·
Replies
18
Views
3K
  • · Replies 30 ·
2
Replies
30
Views
4K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 11 ·
Replies
11
Views
2K
  • · Replies 15 ·
Replies
15
Views
3K