You could experiment with "low frequency optimized" ferrite cores around the power cable. The good news is, they are cheap (USD 2.57) so the cost of an unsuccessful attempt is negligible. The bad news is, they are not snap-on, split cores. You'll need to cut your IEC power cord in the middle, slide on one or more (!!) of these ferrite cores, then splice the cut and insulate it well.
Laird Performance Materials part number LFB143064-000 (link to Mouser sales page) . Datasheet performance shown below. Extrapolate the semilog axes plotted curve, back to 20 kHz. Looks promising for so little money.
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Yes, and that is why a "passive pre-amplifier" is absolute nonsense no matter how often this is repeated.
If input noise is expressed as a voltage and the output measures as a higher voltage (with correspondingly lower current) then wouldn't that be "voltage amplification"?
I don't know. Just asking.
I don't know. Just asking.
Keith Armstrong is the author of the paper linked in the first post. Mr. Armstrong is one of the world's experts in noise & interference.
Hello Bucks B. , Could you please say a little more detail about why one has to preclude the other? Thanks very much.
They refuse any perpetual motion machine patents now.. I suspect that also goes for creating energy too..
you transform 1W power like 1V 1A to 1kV 1mA The same power, but "amplified" voltage, otherwise
you amplify 1V 1A to 100V 1A. This is a voltage and power gain of 100.
you amplify 1V 1A to 100V 1A. This is a voltage and power gain of 100.
yes.....that is arguably not "amplify" i call it transformed to high voltage low current from low voltage and high current in comparison, conservation of matter and energy agrees...
So if I take 1VDC and increase its value to 100VDC, you call that 'transformed'?
I think it is incorrect to use the term transformed unless you are talking passive AC transformers or Laplace. If you convert 1V/1A to 1000V/1mA (AC or DC), you have amplified, even though power in = power out. And chances are, the manner in which you have done that is to add auxiliary power (and by extension, wasted some power through efficiency<100%). But it is still amplification, regardless if power in = power out. I can use amplifiers with both AC and DC quantities, and use them in such a way that I do not change the power represented at input/output.
One conserves matter and energy regardless if the action is passive transformation or amplification.
I think it is incorrect to use the term transformed unless you are talking passive AC transformers or Laplace. If you convert 1V/1A to 1000V/1mA (AC or DC), you have amplified, even though power in = power out. And chances are, the manner in which you have done that is to add auxiliary power (and by extension, wasted some power through efficiency<100%). But it is still amplification, regardless if power in = power out. I can use amplifiers with both AC and DC quantities, and use them in such a way that I do not change the power represented at input/output.
One conserves matter and energy regardless if the action is passive transformation or amplification.
You have not amplified.
You have converted.
Converting is the more general term and is what I meant with transforming.
I've seen it in various text-books. I can't look up which ones I've seen it in, because I got rid of all my old paper text-books some time ago. The Wikipedia article on amplifiers provides references for the definition in three books though.
Okay. Apparently not everyone agrees with some textbook definitions.
For example:
https://inventions.techventures.columbia.edu/technologies/passive-low-noise--CU14031
https://patents.google.com/patent/US8653903B2/en
One thing that occurs to me is that textbooks intended for different purposes sometimes define terms in different ways.
For example:
https://inventions.techventures.columbia.edu/technologies/passive-low-noise--CU14031
https://patents.google.com/patent/US8653903B2/en
One thing that occurs to me is that textbooks intended for different purposes sometimes define terms in different ways.
I have amplified voltage. I can amplify (increase magnitude) or I can attenuate (decrease magnitude).
A power change is optional to the concept of 'amplify'.
With your conception, always qualify with the term 'power amplification'. Like it or not, amplify is just as general a term as is convert.
Assume Rf = 10K, Rs = 1K. As shown, there is no load RL.
Pedantic to discuss bias currents.
Vs = 1V. Therefore, Vo = -10V.
Power delivered by the source = 1 mW.
Power delivered to the load of infinity = 0 mW.
Power therefore has decreased from input to output. Is this circuit therefore an inverting-attenuator?
Voltage has increased from input to output. Is this perhaps why it is called an inverting-amplifier? What does power have to do with the behavior and identification of the circuit?
Sure, the opamp itself is providing power to the passives surrounding the opamp, and this goes to the point in post 31 that power lost to efficiency is independent of the behavior of the circuit to amplify (increase) while perhaps consuming power in the process.
But let's not try to redefine a century of accepted industry practice of identifying the circuit attached as being an amplifier.
Or maybe we need to re-write all our textbooks to use the terms "inverting-converter" and "noninverting-converter". That will help further progress and make things so much more clear...
Pedantic to discuss bias currents.
Vs = 1V. Therefore, Vo = -10V.
Power delivered by the source = 1 mW.
Power delivered to the load of infinity = 0 mW.
Power therefore has decreased from input to output. Is this circuit therefore an inverting-attenuator?
Voltage has increased from input to output. Is this perhaps why it is called an inverting-amplifier? What does power have to do with the behavior and identification of the circuit?
Sure, the opamp itself is providing power to the passives surrounding the opamp, and this goes to the point in post 31 that power lost to efficiency is independent of the behavior of the circuit to amplify (increase) while perhaps consuming power in the process.
But let's not try to redefine a century of accepted industry practice of identifying the circuit attached as being an amplifier.
Or maybe we need to re-write all our textbooks to use the terms "inverting-converter" and "noninverting-converter". That will help further progress and make things so much more clear...
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Obviously further discussing this with you will end running in circles.
I am out.
It can't be stated enough: "amplify" is often, but not exclusively applied to power amplification. If in doubt clarify which you mean.
"to make larger or greater (as in amount, importance, or intensity)"
If you are an RF engineer, amplify would always be power amplification, and "impedance transform" or "impedance matching" is your term for passive amplification (or attenuation). But in general signal processing you have the choice of voltage, current or power.
A good example of a passive voltage amplifier might be a step-up transformer used before a current-buffer or output stage to provide the voltage increase. Not that these work well, but its clearly something that amplifies voltage.
"to make larger or greater (as in amount, importance, or intensity)"
If you are an RF engineer, amplify would always be power amplification, and "impedance transform" or "impedance matching" is your term for passive amplification (or attenuation). But in general signal processing you have the choice of voltage, current or power.
A good example of a passive voltage amplifier might be a step-up transformer used before a current-buffer or output stage to provide the voltage increase. Not that these work well, but its clearly something that amplifies voltage.
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Like in this patent: https://patents.google.com/patent/US8653903B2/en
And this is touted for RF: https://inventions.techventures.columbia.edu/technologies/passive-low-noise--CU14031
And this is touted for RF: https://inventions.techventures.columbia.edu/technologies/passive-low-noise--CU14031