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If filter cutoff is 10 Khz then yes, BW at 1 Mhz goes away.
What is the filter cutoff you want ? 10 Kz or 1 Mhz ?
So you have to attack the source of the noise (which one would do concurrently) first
and then decide what compromises you can live with in the BW of interest. Keep in mind
filters...
"normally" one thinks of a LPF active filter when talking 10 Khz kinds of cutoffs.
Design tools : http://sim.okawa-denshi.jp/en/Fkeisan.htm
https://tools.analog.com/en/filterwizard/
But earlier you ask or a cutoff of 1 Mhz, not recent 10 Khz, so solution quite different
between the two...
If you look at the basic circuit your opamp serves as a window comparator, but also affects
freq because as the window changes the time the RC needs to charge / discharge changes. But
affecting the window trip points changing the amplitude achieved at the inverting input
to opamp to hit the trip...
Hint, you have 3 basic R's that control....
The variable R U7 controls hysteresis of the LM308 being used as a comparator. So yes
it changes trip level AND the freq....So what R would only change the freq, and what R
would control duty cycle ?
Regards, Dana.
If the noise is broadband, as it appears to be until we get a screenshot of FFT
from a fast scope, or a spectrum analyzer, OpAmps may not be the filter of
choice. Especially as they run out of PSRR and G at noise freq of interest, as OpAmp
GBW is a pproached.
if OP wants to attack it after the...
Caution, there has not been dev activity of it recently, but its quite useful. And it
handles multitasking basics.
MPY Blockly similar, much more capability, and dev work seems ongoing.
Regards, Dana.
The G peaking is not in your fdbk loop, so that does not create "instability",
but can overload a OpAmp G stage with too much input signal. When you do
sims you need to use real models of L and C to get actual peaking values.
You can place the ground at U1 input, take a screen shot of the...
Ground input to U2 and then look at noise. If its still there guess is its
from power supply, and thats where L >> C >> Vp & same for Vn should
go.
Using FFT on your scope what does noise look like, post a screen shot.
Regards, Dana.
Probing considerations, scope probe ground nemesis for getting bad readings :
https://download.tek.com/document/02_ABCs-of-Probes-Primer.pdf
30 - 40 mV not uncommon. On micro busses I regularly see 200 mV.
OpAmp PSRR degrades substantially at higher freq, consult data sheet for graph.
Ferrite...
Probing considerations, scope probe ground nemesis for getting bad
readings :
https://download.tek.com/document/02_ABCs-of-Probes-Primer.pdf
The datasheet has extensive recommendations on bypassing and grounding.
Elimination of those caps not a good idea, in fact lead one to find either
they...
Using Tuniot for block programming (ESP32 or ESP8266) easy and fast way for simple programs, everything from
simple control to Client Server apps. Here multicore features of ESP32 used.
Another example : https://www.edaboard.com/threads/verizon-remote-hotspot-controller.400349/
A pile of...
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