A simple low pass filter is, in my opinion, one of the best ways to smooth out noisy data. And you made the process even more simple by your demonstration here - nice job!
Great video and very helpful! I didn't know I could use the function generator in sweep mode; I will check the performance of my self made inductors with this method. Thank you very much!
This is exatly what I have been looking for! A lot of nice people out on RUclips have made "what you need in your lab" and they are very trough to get everything listed up, but none have ever made a "WHY - for what" video. So you are standing with a great list of items, but can't just imagine what it should all be good fore:-)
It would be cool if you talked about the Peak to Peak output voltage from the sig generator and the Peak to Peak you are seeing on the O-scope and how the output loading on the sig gen impacts the readings on the o-scope. Thanks.
Thanks for this video! Something that annoys me is i built a RF highpass filter but its insertion loss is terrible, like 20db (voltage) or so, i dont know what i did wrong, the filter design tools say it should only be about 6db loss. Was thinking im measuring wrong or my equipment is messed up
Some of the most useful purposes for a function generator is to modulate noise onto signals so you can torture your design to see how it fails. The uses are endless really!
The application of white noise to the input of an amplifier/ filter can be used to give a quick display of the amplifier/filters frequency response, as the output noise will be shaped by the response of the unit under test. The only caveat is that the input signal might overdrive the unit under test and may result in intermodulation products from both in band and out of band signal interactions. But this technique is still used in some RF applications, such as the testing of radio aerials and passive filters. One advantage of this form of testing is that it does not necessarily involve expensive test equipment, just an oscilloscope, a diode broad band noise source and a diode probe RF detector.
It might have been more interesting to sweep a Wein bridge filter, two resistors and two capacitors gives a resonant peak by virtue of the interaction of a low pass high pass combination. There was an instrument known as a wobbulator, that used a combination of a voltage controlled oscillator and an oscilloscope to provide a poor man's network analysiser. The sweep voltage was used to drive the scope X axis, while a peak detector connected to the scope y input was used to display the network under test output voltage. This provided a display of the network's amplitude response, a bode plot. When used at radio frequencies. It facilitated the setup of IF filters, in the day when these were made up of a cascade of tuned capacitor/inductor filters. It was very satisfying to see the network response displayed in real time, and be able to adjust the filters, by tuning the inductor cores, to give a flat bandpass response. ( I think the test equipment was called a wobbulator because of the wobbling sound it made when listened to on the receiver speaker or the speaker built into the equipment.) I once used a similar technique to tune an eight pole butterworth Sallen and Key op-amp filter, to give a maximum flat bandpass response. It turns out that such filters can be tuned by adjusting the voltage gain of each two pole section. The math functions on a modern storage scope makes it relatively easy to configure it, in combination with a waveform generator, as a network analyser . The scope can be programmed to due the log peak detection and even the phase measurement. Displaying both amplitude and phase bode plots. Very useful if you are interested in filter design.
It is very usefull special if you are playing with mains voltage aka triacs and want to feed sinosoidal signal to do the Zero Cross Control eg to an Arduino, before blowing something, even with opamp and opto-couplers, isolation transformer.
Small point but since you're measuring a voltage wave form, isn't the 50% reduction in signal height at the -6dB level and not at the -3dB level, as it would be for power(watts)? The -3dB level for voltage is approximately 30% reduction in sine wave height.
To me that resistors looks to have orange-orange-brown bands. Simple mistake of either seeing or just saying wrong color. Signals on the scope indicate 330 Ohm resistor with 100nF (+ some nF due to the tolerance) capacitor.
resistor clearly is a 33 ohm, not 330. But besides misspeaking, 330 was also used in the calculation, which came out as 4,8 Khz. Now, if you use 33 in the calculation, one comes out at 48 Khz (the expected one order of magnitude difference) - which was not what we saw on the scope. What gives?
@@bobcuyt4675 I do see it as brown in the video (330 ohm), so I think he just miss-spoke as "black". 330 ohms does seem to be verified by the scope, where it does appear to go through about half power (-3db) level around the 4.8Khz mark. Note that half power is approx 0.7 amplitude (voltage level).
A Spectrum Analyzer would be most handy doing this. You can down load and use a Audio Freq Lap Top Software version easy enough. Always build a Interface to protect your lap top's audio input. Of Course my Lenovo LT has the most crappy audio input available and I'm limited to a single channel doing so.
Historically, orange, orange, black is 33 ohms. 330 ohms would be orange, orange, brown. Brown stands for 10 to the first power, red is 10 to the 2nd power, etc. I checked my Radio Shack resistor calculator just to make sure.
Depends on the number of bands. There are 5 band codes and 4 band codes. What you say is true for four band codes. 5 band codes however have three significant digits followed by a power of 10.
I checked that his resistor had only 4 bands before posting. Further, he states three separate color bands, not four, so the proper standard is clear in this case. My junk box contains both types, so I not only check the color bands these days, but I also check the actual resistance with a DMM since used resistors can vary quite a bit depending on their tolerance and their history.
Nice try, but you really missed out on the real world use of viewing the overall reponse of something using a sweep generator. Have a watch of w2aew channel's vid on sweep generator use (vid #45). For actual measurement use I suggest watching eevblog #396 video.
A simple low pass filter is, in my opinion, one of the best ways to smooth out noisy data. And you made the process even more simple by your demonstration here - nice job!
Thanks. How's the new little one?
@@learnelectronics Eating all the damn time!! Otherwise healthy and growing quick. Thanks for asking :)
I like your videos a lot. Please keep them coming. Thanks.
Very good presentation. Highly instructive for a practical application. ⭐️
Nice example to get an idea what to do with such a device 👍 This rookie (me) had no idea 😊
May I suggest watching w2aew youtube channel video on sweep generator (vid #45). His explanation is of more practical use.
@@MikeB_UK Thanks Mike 👍 I Will 😊
Great video and very helpful! I didn't know I could use the function generator in sweep mode; I will check the performance of my self made inductors with this method. Thank you very much!
A very nice video from a very nice guy.
Really, really interesting!!!
Thanks a lot, dude! 😃
This is exatly what I have been looking for!
A lot of nice people out on RUclips have made "what you need in your lab" and they are very trough to get everything listed up, but none have ever made a "WHY - for what" video. So you are standing with a great list of items, but can't just imagine what it should all be good fore:-)
Great Video! This a great example
For understanding function generator and oscilloscope.
Don't understand all of this but a big thumbs up anyway!
Thanks for the explanation and demonstration.
Thanks for sharing that! Suggestion: Make a video using FFT function.
They are also great for isolating noise in a circuit you are trying to fix.
Great training video, regards from Hannover Germany
It would be cool if you talked about the Peak to Peak output voltage from the sig generator and the Peak to Peak you are seeing on the O-scope and how the output loading on the sig gen impacts the readings on the o-scope. Thanks.
Thanks for this video! Something that annoys me is i built a RF highpass filter but its insertion loss is terrible, like 20db (voltage) or so, i dont know what i did wrong, the filter design tools say it should only be about 6db loss. Was thinking im measuring wrong or my equipment is messed up
Great explanation, as always.
Some of the most useful purposes for a function generator is to modulate noise onto signals so you can torture your design to see how it fails.
The uses are endless really!
The application of white noise to the input of an amplifier/ filter can be used to give a quick display of the amplifier/filters frequency response, as the output noise will be shaped by the response of the unit under test. The only caveat is that the input signal might overdrive the unit under test and may result in intermodulation products from both in band and out of band signal interactions. But this technique is still used in some RF applications, such as the testing of radio aerials and passive filters. One advantage of this form of testing is that it does not necessarily involve expensive test equipment, just an oscilloscope, a diode broad band noise source and a diode probe RF detector.
It might have been more interesting to sweep a Wein bridge filter, two resistors and two capacitors gives a resonant peak by virtue of the interaction of a low pass high pass combination.
There was an instrument known as a wobbulator, that used a combination of a voltage controlled oscillator and an oscilloscope to provide a poor man's network analysiser. The sweep voltage was used to drive the scope X axis, while a peak detector connected to the scope y input was used to display the network under test output voltage. This provided a display of the network's amplitude response, a bode plot. When used at radio frequencies. It facilitated the setup of IF filters, in the day when these were made up of a cascade of tuned capacitor/inductor filters.
It was very satisfying to see the network response displayed in real time, and be able to adjust the filters, by tuning the inductor cores, to give a flat bandpass response. ( I think the test equipment was called a wobbulator because of the wobbling sound it made when listened to on the receiver speaker or the speaker built into the equipment.)
I once used a similar technique to tune an eight pole butterworth Sallen and Key op-amp filter, to give a maximum flat bandpass response.
It turns out that such filters can be tuned by adjusting the voltage gain of each two pole section.
The math functions on a modern storage scope makes it relatively easy to configure it, in combination with a waveform generator, as a network analyser . The scope can be programmed to due the log peak detection and even the phase measurement. Displaying both amplitude and phase bode plots. Very useful if you are interested in filter design.
Very helpful...
1:18 Orange Orange Black the last time I checked some 40yrs ago till now was 33 ohm!
It is very usefull special if you are playing with mains voltage aka triacs and want to feed sinosoidal signal to do the Zero Cross Control eg to an Arduino, before blowing something, even with opamp and opto-couplers, isolation transformer.
Cool video. Reproduced this easy project but do not understand why the phase changed?
Signal slows through the filter
Interesting Video, pls keep it up :)
I saw in your comments about your hands being fat that used to be me now I've lost 92 lb and I have no more illnesses
Hi, could you make a Video about how to use the 74hc595n with Arduino Uno
Small point but since you're measuring a voltage wave form, isn't the 50% reduction in signal height at the -6dB level and not at the -3dB level, as it would be for power(watts)? The -3dB level for voltage is approximately 30% reduction in sine wave height.
correct, 50% voltage drop is -6dB, dBV = 20Log(Vi/Vo) power in dB is 10Log(Vi/Vo)
Thats why i hate dB honestly its confusing to know if its for voltage or power, etc
Anyway 3db is 3db
1:16 ... 33ohm actually? Or the last ring is brown. Great presentation as always, thanks.
To me that resistors looks to have orange-orange-brown bands. Simple mistake of either seeing or just saying wrong color. Signals on the scope indicate 330 Ohm resistor with 100nF (+ some nF due to the tolerance) capacitor.
I misspoke
@@learnelectronics Thanks for triggering my OCD LOL. "Orange orange black, that would be 330 ohms" gave me one of those moments.
resistor clearly is a 33 ohm, not 330. But besides misspeaking, 330 was also used in the calculation, which came out as 4,8 Khz. Now, if you use 33 in the calculation, one comes out at 48 Khz (the expected one order of magnitude difference) - which was not what we saw on the scope. What gives?
@@bobcuyt4675 I do see it as brown in the video (330 ohm), so I think he just miss-spoke as "black". 330 ohms does seem to be verified by the scope, where it does appear to go through about half power (-3db) level around the 4.8Khz mark. Note that half power is approx 0.7 amplitude (voltage level).
Is this like a curve tracer?
I just became a patreon :)
Thank you!
A Spectrum Analyzer would be most handy doing this. You can down load and use a Audio Freq Lap Top Software version easy enough. Always build a Interface to protect your lap top's audio input. Of Course my Lenovo LT has the most crappy audio input available and I'm limited to a single channel doing so.
Historically, orange, orange, black is 33 ohms. 330 ohms would be orange, orange, brown. Brown stands for 10 to the first power, red is 10 to the 2nd power, etc. I checked my Radio Shack resistor calculator just to make sure.
Depends on the number of bands. There are 5 band codes and 4 band codes. What you say is true for four band codes. 5 band codes however have three significant digits followed by a power of 10.
I misspoke
@Stevey Canuck And if you hear "From the Halls of Montezuma..." it's probably the Marine Band.
I checked that his resistor had only 4 bands before posting. Further, he states three separate color bands, not four, so the proper standard is clear in this case. My junk box contains both types, so I not only check the color bands these days, but I also check the actual resistance with a DMM since used resistors can vary quite a bit depending on their tolerance and their history.
try timebase around 1 sec....
Nice try, but you really missed out on the real world use of viewing the overall reponse of something using a sweep generator. Have a watch of w2aew channel's vid on sweep generator use (vid #45). For actual measurement use I suggest watching eevblog #396 video.
Poor mans tracing gen. :) Things can be improved, and for 10MHz, it is cheap to do different ways too, but sure why not.