Talk:Maxwell bridge
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Clarification
editThis is in fact a Maxwell-Wien-Bridge, which is comparing an inductor with a capacitor. The Maxwell bridge compares two inductors. Best regards. Hack —Preceding unsigned comment added by 192.53.103.101 (talk) 13:30, 25 March 2008 (UTC)
real product?
editas opposed to, a fake one? --UltraMagnusspeak 11:41, 5 June 2010 (UTC)
circuit schematic wrong and confusing
editC2 is a variable capacitor, and R2 is a variable resistor in the usual configuration, i.e. one has a breadboard set up to try this. Also, the inductor is usually a single component; the circuit model represents a real inductor's DCR as a separate series resistor, but there won't be a physical component on the breadboard for this resistor. This isn't made clear in the text or schematic. It is unlikely that one will achieve a balanced bridge using fixed components for R2 & C2 any time soon, because the real and reactive components of the inductor's impedance usually won't have standard E12 or E24 values. Sbalfour (talk) 05:14, 12 October 2017 (UTC)
Technical maintenance tag
editI think the tag stays for now, but this article is actually not that technical - a rudimentary understanding of AC electronics at least through Kirchoff's laws is sufficient. One does not need to understand Maxwell's Laws for example, though the bridge bears his name. What the article lacks, is some fill-in struture so someone unfamiliar with how and why this bridge works can follow the text without doing a chunk of pencil and paper circuit analysis. The circuit doesn't stop working when the Q is outside the range 1-10; it in fact should work reasonably well for Q down to 0.1 (exceedingly poor inductor), and usably well for Q from maybe 0.04 to 25. For very low and very high Q, the parasitic properties of real components like ESR of the cap and parallel capacitance of the inductor may overshadow the components modeled in the schematic. A circuit that attempts to model high/low Q components needs to properly model all the properties of physical components, and include complementary components in the balancing arm of the bridge. Some adequate explanation along these lines should probably appear in the text, because real inductors with Q higher than 10 aren't rare. Sbalfour (talk) 05:43, 12 October 2017 (UTC)
"simpler" bridge type(s)?
editIn the last paragraph, I think what is referred to is use of a Maxwell-Wien bridge with a capacitor and resistor in the antipolar arm of the bridge instead of a Maxwell inductance bridge with an inductor and resistor in the polar arm. Measuring an inductor relative to another inductor is logically consistent, but hardly "simpler" - the calculations are analogous. The statement is correct in that mutual inductance and EMF may obviate use of a Maxwell inductance bridge.
Misuse of the word "resonance"
editThe second paragraph claims that the circuit is in resonance (https://en.wikipedia.org/wiki/Electrical_resonance) when the bridge is balanced but this is not true. The bridge is balanced when the source voltage is divided to equal voltages (equal in both magnitude and phase) by both sides of the bridge. For this to occur it is not necessary for any of the four arms' impedance or reactance to equal that of any other arm which would be required for resonance. In fact the arm's impedances or reactances can be wildly different during balance. To see this using an analogy consider a Wheatstone bridge with 9 and 1 mega-ohms on one side of the detector and with 900 and 100 ohms on the other side of the detector. This Wheatstone bridge will be balanced because the source is divided by 10 on both sides of the detector. But no arm has an impedance equal to any other. — Preceding unsigned comment added by 209.166.73.140 (talk) 15:00, 22 October 2019 (UTC)