Questions tagged [polarity]
For questions about polarity considerations in electronics due to circuit components with polarity (e.g., diodes, transistors, polarized capacitors, batteries, etc.), polarity of quantities directional quantities (such as currents, voltages, electromagnetic fields, etc.), polarity symbols, etc.
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Is this the appropriate way to wire two dynamic mic capsules to an XLR connector? What polar pattern will this microphone have?
I have a Sony F-99S microphone, with two dynamic capsules facing opposite directions. It was originally wired in stereo, with two unbalanced outputs. I am thinking I'll combine them to get a figure-8 ...
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Is this simple battery charger safe?
While experimenting on transistors and current flowing I came to the idea to set up this simple circuit
It's weird...
...to see a positive voltage from the negative side of the battery on the right.
....
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Reverse Polarity Circuit Protection Between Two Power Sources
I’m working on a circuit that is primarily powered by a vehicle battery. However, it also requires a backup power source, which is a secondary 12V lead-acid battery with a smaller capacity.
Since this ...
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Confusion on Voltage Divider Polarities
Taken from Dorf and Svoboda Intro to Circuits 9th ed. P 5.4-15:
Consider the circuit below, which is basically a system of voltage dividers:
My book says that $$V_\text{oc} = \frac{32 \cdot 20}{32+96}...
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Ground Protection Design Against Accidental 12V Miswiring
I'm working on a circuit that is primarily powered through a USB connector (5V and GND). The same system includes an I/O connector with two 12V trigger inputs and a GND reference.
To prevent potential ...
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Having trouble understanding current polarity
Taken from Problem 3.6-10 in Svoboda and Dorf's Introduction to Circuits, 9th Ed.
I am asked to solve for the value of \$i_b\$ in the below circuit:
I redrew the circuit in accordance with the ...
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Reverse polarity protection with LM74700
I am trying to understand a reference design containing the LM74700, in particular the reverse polarity protection and the role of the bulk (?) electrolytic capacitor (47 µF) and the other caps in ...
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Is there a maximum forward voltage limit for diodes like the 1N4007?
I'm working on understanding the behavior of diodes under high forward voltage. For example, if I connect a 1N4007 diode in forward bias to a high-voltage DC source, say 1000 V, but I limit the ...
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Why not double the radio bandwidth using polarization?
Recently I understood a lot about EM waves. As I understand, having two, orthogonal direction (most probably a horizontal and in a vertical one) waves could transfer data independently from each other....
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Physically/fundamentally/literally, why does a significant voltage not develop across a diode in forward bias?
I am asking for a fundamental and physical explanation of why, not formulas.
Let's take an ideal diode. Let's say I have some voltage source not big enough to breakdown and destroy the diode, but much ...
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This is exactly the wrong way to connect this DC circuit breaker, is it not?
This is another little spin-off question of the main one:
DC breakers does polarity really matter? where I want to avoid that it gets flagged as a question that's moving target.
One answer that has ...
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DC breakers does polarity really matter?
To route the 25 mm2 cables there is a clear need to have + on the left and - on the right. But two of these 3 DC breakers are giving the impression that they want - on the left and + on the right. I ...
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Generating -3 V Vbb for an ailing Amiga Alice chip (NMOS)
Background: I have an Amiga 1200 computer (ca. 1992) with a problem that seems to be caused by a bad Vbb voltage associated with the Alice chip (address generator, DMA controller, blitter, etc.). As I ...
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Harness for trailers
My friend is making a custom harness for trailers for a company and he said that instead of a negative wire for the LED lights the company is just tapping straight into the bed of the trailer. So for ...
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Testing to find polarity of PCB power connector
I've got a PCB I ordered from China. It required a 5V input voltage through a barrel jack. The issue is there is no sign showing the polarity (positive or negative center) so I don't want to connect ...
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