Milestone-Proposal talk:Anderson Bridge

Advocates’ Checklist

1. Is proposal for an achievement rather than for a person? If the citation includes a person's name, have the proposers provided the required justification for inclusion of the person's name?
2. Was proposed achievement a significant advance rather than an incremental improvement to an existing technology?
3. Were there prior or contemporary achievements of a similar nature?
4. Has the achievement truly led to a functioning, useful, or marketable technology?
5. Is proposal adequately supported by significant references (minimum of five) such as patents, contemporary newspaper articles, journal articles, or citations to pages in scholarly books? At least one of the references from a peer-reviewed scholarly book or journal article. The full text of the material, not just the references, shall be present. If the supporting texts are copyright-encumbered and cannot be posted on the ETHW for intellectual property reasons, the proposers shall email a copy to the History Center so that it can be forwarded to the advocate. If the advocate does not consider the supporting references sufficient, the advocate may ask the proposer(s) for additional ones.
6. Are the scholarly references sufficiently recent?
7. Is proposed citation readable and understandable by the general public?
8. Does the proposed plaque site fulfill the requirements?
9. Is the proposal quality comparable to that of IEEE publications?
10. Scientific and technical units correct? (e.g. km, mm, hertz, etc.) Are acronyms correct and properly upperercased or lowercased?
11. Date formats correct as specified in Section 6 of Milestones Program Guidelines? https://ieeemilestones.ethw.org/Helpful_Hints_on_Citations,_Plaque_Locations

Reviewers’ Checklist

1. Is suggested wording of the Plaque Citation accurate?
2. Is evidence presented in the proposal of sufficient substance and accuracy to support the Plaque Citation?
3. Does proposed milestone represent a significant technical achievement?
4. Were there similar or competing achievements? If so, have the proposers adequately described these and their relationship to the achievement being proposed?

Original Title and Citation as submitted. Uploaded by -- Administrator4 (talk) 15:34, 14 March 2023 (UTC)

Anderson Bridge 1891

The Anderson Bridge measures inductance in an ac bridge. The unknown inductance is compared with a standard fixed capacitance, which is connected between two arms of the bridge. It works in a similarly to the Wheatstone Bridge, used to measure resistance. Anderson's method is capable of precise measurements of inductance over a wide range of values from a few micro-Henrys to several Henrys

Advocate's address to the proposers -- Savini (talk) 16:39, 25 February 2024 (UTC) -- Savini (talk) 16:39, 25 February 2024 (UTC)

I have just been appointed as the advocate of your proposal. It will be a pleasure for me to work with you in processing the application

The names of IEEE technical Societies that may be interested in the subject of the application: Instrumentation and Measurements Society Magnetics Society Power Electronics Society

200.-250 words abstract:

In the mid 19th century, as the field of electrical engineering was evolving, there was great interest in the measurement of electrical components viz. resistance, inductance and capacitance. Michael Faraday and Joseph Henry independently discovered inductance in 1831/32. James Clerk Maxwell introduced a ballistic deflection method for measuring inductance in 1865. This was a variation on the Wheatstone Bridge (1843) for measuring resistance. The first bridge to measure inductance was the Maxwell Bridge based on the principle of balancing the L/R time constant of the inductor against a known RC time constant of a capacitor. Several modifications followed and the most famous one was the Anderson Bridge (1891) named after Alexander Anderson, Professor of Natural History at the Queen’s College, Galway, now known as the University of Galway. The Maxwell Bridge, was based on the deflection of a ballistic galvanometer, which was difficult to calibrate due to its dependance on a moving coil to detect small movements near the balance points. The Anderson Bridge removed this obstacle by balancing the L/R time constant of an unknown inductor with the stable RC time constant of a capacitor. The Anderson Bridge became the de facto bridge for measuring inductance, as described in the U.S. Bulletin on the Bureau of Standards. The Anderson Bridge remained the standard bridge for measuring inductance until the advent of digital methods in the 1970’s. Most undergraduate textbooks up until that time referenced the Anderson Bridge for the measurement of inductance.

Antonio Savini