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Is a 2N3906 an appropriate replacement for a BC158(B) in audio amp circuit?

On a long but educational process repairing a vintage German stereo. I have identified a failed (shorted) PNP transistor in the power amp section. (Schematic with highlight is below.) The part on the actual board is a BC158B; the schematic specifies only “BC158”. The only difference between the BC158 and the B variant is the […]

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Is a 2N3906 an appropriate replacement for a BC158(B) in audio amp circuit?

On a long but educational process repairing a vintage German stereo. I have identified a failed (shorted) PNP transistor in the power amp section. (Schematic with highlight is below.) The part on the actual board is a BC158B; the schematic specifies only “BC158”. The only difference between the BC158 and the B variant is the […]

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I don’t understand the outcome of the solution for a circuit with two voltage sources and an inductor

I have solved this circuit problem and I don’t really understand the result in terms of power for the two sources. So for source one, it is clearly generating real and reactive power. For source two, it is consuming, based on the current going out of the source. The reactive power consuming reactive power. The […]

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How are the neat sinc function shaped carriers produced in OFDM?

I am learning about OFDM and QAM. Every explanation I have read illustrates how the separate carriers are sinc functions that are arranged to overlap in a nice orthogonal way so as to cancel out interference from neighbouring carriers. The part I don’t understand is how is it possible to generate these neat perfectly overlapping […]

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Smd resistor code= IEE

![r28=iee what is meaning of iee code of smd resistor? ]1

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Where to find standards for SMPSs [closed]

I am working on a project that includes a Switch Mode Power Supply. I need some numbers, ranges, for safety reasons and beacuse I want to use it equally as other devices and with other devices plugged. For example: I can find out the voltage in the mains (230 V 50 Hz), but not the […]

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What is the length of one symbol sent through WiFI?

Having a WiFi emitter sending a frame how much time does each symbol takes? and therefore which distance do they spread over? This depends on the Modulation Coding Scheme. I would like to know which of the various 802.11 norm has the shortest symbols. Here is and example with 802.11b: – at 11Mb/s using DQPSK […]

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Replace everything in the circuit except the 3 A source by its Thevenin equivalent circuit and use the result to find V1

Replace everything in the circuit except the 3 A source by its Thevenin equivalent circuit and use the result to find V1. This is my solution but the teacher said it is wrong and i do not know how to fix it.

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Replace everything in the circuit except the 3 A source by its Thevenin equivalent circuit and use the result to find V1

Replace everything in the circuit except the 3 A source by its Thevenin equivalent circuit and use the result to find V1. This is my solution but the teacher said it is wrong and i do not know how to fix it.

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What is the symbol for this very site? What type of diode?

What specific type of diode (presumably) is the logo for Electrical Engineering Stack Exchange?