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3 votes

Generating a 1pps signal with ~0.1ppm accuracy

The easiest solution for you is probably a GPS receiver with a 1pps output (many of the demo boards have a pps signal. Like the GPS-16329 by Sparkfun). The other possibility for the accuracy you want ...
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2 votes
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Generating a 1pps signal with ~0.1ppm accuracy

Because pps (or whatever frequency) pulses are typically generated from dividing a clock, the accuracy of those pulses (in terms of frequency/ period) would be straight away the accuracy of the ...
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1 vote

Ring oscillator not oscillating

The 1Meg resistors are so high that the current gain of a typical BJT won't give a net gain around the loop of over unity, so no oscillation. MOSFETs don't have a problem with this high resistance. To ...
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  • 13
2 votes

Can this circuit with two resistors oscillate?

Quote (emnha): ....I'm interested in the theory if two R, -R can oscillate with frequency unspecified No - this is imposible because this would violate the oscillation condition which requires that ...
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0 votes

External RC oscillator fuse programmed instead of external crystal fuse

You can override the crystal with an external 1..4MHz square wave generator at XTAL1. An Arduino output with a fast set_bit/clear_bit loop can provide this if you don't have a function generator at ...
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  • 146
1 vote

Can this circuit with two resistors oscillate?

UPDATE: EE&O, for those who are interested (and would check ... already pointed out by @Tony Stewart EE75 ...) in the behavior of the "negative" resistor, here is an example of what ...
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  • 3,628
2 votes

Can this circuit with two resistors oscillate?

This theoretical condition produces an infinite current (or a singularity) when R+ & R- = 0 and thus an infinite voltage across either resistor for any input voltage from a theoretical ideal ...
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2 votes

Can this circuit with two resistors oscillate?

It doesn't oscillate. It only has current opposite to the instantaneous voltage. There is no feedback effect, so no oscillation.
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1 vote
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Simple Diode Mixer Help

In an unbalanced single diode mixer it is important to provide a DC path through the diode to ensure that the bias conditions are correct. There should be significant conduction occurring during the ...
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1 vote
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External RC oscillator fuse programmed instead of external crystal fuse

In the external RC oscillator mode, the oscillator block onboard the chip will not work with a crystal. You would need to connect a resistor and a capacitor as shown in app note AVR051: If it's hard ...
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4 votes

Why don't simulators work with a self-oscillating voltage booster circuit using a transformer and a transistor?

These sorts of simple self oscillating schemes rely on transformer saturation to define the on time by volt seconds applied to the winding .This is a close relative to the blocking oscillator .You ...
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6 votes
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Why don't simulators work with a self-oscillating voltage booster circuit using a transformer and a transistor?

It's not the simulator that's isn't working. The challenge is to accurately model your circuit: not just its connections, but also the circuit elements. Even then, simulations can bomb out when they ...
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1 vote

Where are the transistor number 18 and 21 in op amp 741 according to Wikipedia?

Compare the circuits in datasheets from different manufacturers: https://eecs.oregonstate.edu/education/docs/datasheets/LM741.pdf https://www.st.com/resource/en/datasheet/ua741.pdf https://www.ti.com/...
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7 votes

Why don't simulators work with a self-oscillating voltage booster circuit using a transformer and a transistor?

The transformer winding in the collector is the wrong way round. You need to swap the two connections such that when the collector goes towards ground, the base goes positive. The dots on the windings ...
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1 vote

When should we switch from an internal FPGA oscillator to an external one?

(This answer assumes we are talking about internal RC oscillators) In general, being able to use an internal RC oscillator vs a dedicated crystal or oscillator is not a question of production quantity,...
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4 votes
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Relation between number of RC networks and phase shift in RC phase shift oscillator

There are many ways to determine the transfer function of a cascaded \$CR\$ networks such as the one you've shown. I am using the fast analytical circuits techniques or FACTs as described in my book ...
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0 votes
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Which part of this transistor model op amp represents pin 5?

Your op-amp oscillator is incorrectly drawn: - You have the inputs swapped and it will no-longer behave like a relaxation oscillator. Regarding which pins are represented in your transistor circuit: -...
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2 votes
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How can I build a current controlled 50% duty cycle oscillator from two CMOS inverters?

After fiddling with this for a few days, I came up with the following circuit: simulate this circuit – Schematic created using CircuitLab Here V1 is the logic voltage source and D2, D4 are the ...
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  • 490
1 vote

Effects of too-frequent serrations in vertical sync pulse on analog horizontal deflection oscillator

Regarding just the sweep oscillators, ignoring effects on the video signal itself: Depending on how far back you go -- the standard method AFAIK is a blocking oscillator. Roughly speaking, this is a ...
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0 votes

How does a ring oscillator get voltage?

It is simple. Lets assume X = low, then Y = high, Z = low. If Z is low, X should be high. This seems to be a contradiction to our assumption, but it is not. There is a gate delay for each inverter of ...
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2 votes

How does a ring oscillator get voltage?

Logic gates are voltage controlled complementary (CMOS) switches between Vdd and Vss. If you have an odd number of inverters in a loop you have negative feedback towards the input threshold as the ...
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1 vote

How does a ring oscillator get voltage?

Like most oscillators, oscillation will start from intrinsic noise or disturbances in the circuitry. At startup the logic gates will be biased into their linear region. If the loop gain is greater ...
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7 votes

How does a ring oscillator get voltage?

All logic circuits need power supplies to work. They don't work without power. Logic circuits may be drawn without power input for simplicity, like in this case.
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-6 votes

How does a ring oscillator get voltage?

It doesn't by itself.You need to put a trigger pulse then remove the trigger pulse in order to have oscillation.
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0 votes
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Using an oscillator instead of a crystal on W5500

The CMOS/TTL part you showed is expected to work, as long as you run it on 3.3V Vcc.
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  • 210
0 votes

Oscillator without active components

Early “candlestick” telephones oscillated when the carbon microphone was brought close to the earphone.
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2 votes

Oscillator without active components

You can use a mechanical vibrator circuit as done in the vacuum tube days for power inverters to generate B+ voltage. simulate this circuit – Schematic created using CircuitLab
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  • 3,745
1 vote

Oscillator without active components

For an electrical oscillator, you need a component (components) that have power gain. This means e.g. a transformer (alone) isn't sufficient because it has voltage gain, but not power gain. Passive ...
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  • 12.4k
0 votes

Oscillator without active components

Every passive resonant RLC is lossy and eventually decays. But very high Q series resonant circuits be made with occasional pulses (active) to sustain Oscillations. Series Q is defined as the ...
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