I guess it's time to give some background information about things popping up on this channel.
The majority of the material this far is material from the courses I teach at Uppsala University. Recorded lectures which I upload to RU-vid will not be listed but only available to course students with the corresponding direct link.
Additional material which I happen to record and where I think there might be a broader interest will be listed on this channel - and who knows into what it will develop, if this platform allows...
Should be slightly radioactive. 87Rb is not stable. The "Helmholtz-coil" is the tuning element. With it's magnetic field the frequency of the hyperfine transistion is modulated.
honestly I don't know when the term "flip-flop" for the electronic circuit came up first, also Wikipedia does not really say anything decisive. en.wikipedia.org/wiki/Flip-flop_(electronics) It is a circuit with two different states and between these it can flip like you flip a coin - so perhaps that's the origin.
Arduino framework increases RAM usage a lot and I don't like cpp files. This is exactly what I was looking for, hopefully I'll be able to compile it into a much smaller size
Extremely thoughtful and careful teardown, actually this video is more a disassembly. I love trying to find out how these sorts of devices work so I really enjoyed listening to you impart your knowledges as you progressed A1
I have one final question - and I apologize for not putting them all in one: I see we have sine graph shown but could we just as easily show the cosine graph by changing the perspective so the imaginary and real axis change places?
If you knew the system behind youtube and how comments are presented to makers, you would have posted everything as a single question. Adding to some other comments here and there makes it a mess behind the scenes to find all your small questions... yes, sine and cosine do not really matter, yet I start by showing a sine wave which starts at 0, and in order to maintain this context I need to rotate the axes at a later point....
@@MathCuriousity When I made this animation in povray I had a certain context with my students in mind - it was never meant to be a fully self-sustained, self-explaining video. I mostly put it on youtube because it was the simplest way to make it accessible for my students and because I wanted to show how to make mathematical animations in povray. I rotated the curve, because we usually tend to comprehend the real part of the complex function as the observable quantity in the real world, and in the context of electronics the observable quantity (usually a voltage) is shown on the vertical axis of e.g. an oscilloscope.
yea... pastebin isn't the best place for it. ""Error, this is a private paste or is pending moderation. If this paste belongs to you, please login to Pastebin to view it. ""
Yo is there a way to use this to visualize a 3d sine wave on the tonic (root note in music) and 7th note of the scale this could potentially give insight into a 4d visualization. Let me know, thanks
I did a terrible job explaining. In music if you use a visualizer to look at the frequencies of 2 sine waves tuned together (“tonic note” played with the “7th” note) they harmonize and their interference pattern creates a 3d illusion. So if we could simulate what this video does with 2 specifically tuned sine waves played at the same time they may create a 4d shape or at least something cool. Lowkey I’m garbage at explaining this shit but if you need help just copy my comment into chat gpt and ask for it to rephrase it. I appreciate it!
@@WesLindstrom-Chalpin-tn6ol you can visualize the addition of sine waves, but I would not call it 4D. You can have a look at 3blue1brown's videos and learn how to use his tool Manim.
@@user-xb9wb8sc9l it shows how a projection of a rotating vector in the complex plane onto the real axis gives a sine wave proceeding in time. It's the basis of treating the impedance of capacitors and inductors as imaginary entities in the so-called j-omega method, a special case of the Laplace transformation, used in electronics and electrical engineering.
@@user-xb9wb8sc9l I don't understand what your problem with my animation here is. It is "complex" in the meaning that it shows sine and cosine on the complex plane as part of the calculation of phase angles in the ac analysis of electronic circuits. There is nothing "complex" about it in the meaning of "complicated"
I have my own construction based on Thomas Fischl's USBasp which is open source. There a lot of commercial clones of the USBasp available from Aliexpress, eBay etc. They cost somewhere between 3$ and 10$
What don't you understand and to which level of detail do you want to understand the I2C bus? I would recommend to read some documentation rather than relying on a youtube video. NXP - or rather former Philips - is the inventor of I2C and they have the standard document: www.nxp.com/docs/en/user-guide/UM10204.pdf
@@uwezimmermann5427 You are great at explaining and I am interested too. Like a typical circuit with data input from a sensor and output on a LCD or something while using a MC as 328p and coded in AVR-C?
I am just using the NE555 model from the [Misc] category in LTSpice - what kind off error do you get? What version of (LT?) Spice are you using? Where did you get your model from? In addition I also included the TLC55x model from TI to my LTSpice which also works fine - you can find it on the TI website www.ti.com/product/TLC555
did you see my follow-up video on the topic? ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-BKO1rYMPF_k.html you enter it as "board_build.f_cpu = 1000000UL" (for f=1MHz) in the settings in platformio.ini
I would need to check, but I am almost convinced that it should be RS232. You should be able to test this by measuring the idle voltage on the TX-line. If it is positive then it should be either TTL 3V/5V, if it is negative it is certainly RS232.
Excellent explanation. I’ve been working on a couple of pwm projects and have been completely confused by the difference. My only criticism of this video is you didn’t explain why someone would use fast over phase correct or vice versa :). Either way this gave me a good start. Thanks!
This video was planned as a short additional material for my students, not as a self-explanatory, full tutorial... if I ever find the time... Just in short, fast-mode gives you twice the pwm frequency at otherwise same performance, but it is also the standard mode in most cases. If you run two channels at different duty cycles still they will either be switched on or off at the same time giving you larger current transients in total. Phase-correct pwm not only distributes the switching times more widely, it also can be used if you need to avoid overlaps between switching, e.g. if you use one channel for the switching of the upper and one for the lower transistors in a H-bridge.
Thank you for the teardown! It was very interesting to see the insides of a small model like this. It would be great to see the various control signals as the oscillator turns on and locks in.
Yes, it probably would be - however, I don't think I will disassemble my working units, and also it will be difficult to probe the unit during operation, because of the compact design.
Thank you so much, this is really helpful. Since I am using the Arduino UNO as programmer, please let me add the relevant command here. I think it will be useful. `avrdude -pm328p -c arduino -P /dev/ttyACM0`
one more thing i will like to add. when you were testing MRF321 in diode mode, it is important to check BJT in fwd , reverse mode and in between Collector and emitter. these three tests are conclusive to check good or bad devices. three test lead may be de soldered to isolate the device
Thank you for your comments - actually I have no ambition to fix this unit, since I got two working ones. I keep this one as educational material for my students.
very nice and detailed information. could you find what actually was wrong with this unit. to make it work, one need right temprature (MRF tx and resistors), 6.8 Ghz feild ( can be verified using feild probes and spectrum Analyser), the continuity of coil can be verified using DMM. for infrared lamp i am not sure but can be visible using from digital camera with IR Filter removed. photo sensor could be checked using DMM and or scope. i have one of these, in which lock bit is not going down. Shell gets warm so i assume MRF is okay. Rest i need to check. I may be wrong my assumptions, so please guide
It is very difficult to realistically simulate microcontroller code. The microcontroller is supposed to react to events from the outside in realtime... There are emulation/simulation tolls around, but as far as I know none is integrated into PlatformIO.
that could almost sound like a question I ask my students... If you are using an ATmega and you are using the same timer for both pwm-channels, then you can change the duty cycles individually by setting the OCRxA and OCRxB to different values. E.g. for Timer1 this would be OCR1A and OCR1B. Now you can use one of the ADC channels to read the potentiometer value and use this value to set the corresponding OCR-value. In Timer1 there is are 10bit PWM modes which suit the 10bit ADC of the Atmega ideally. In the main loop you would periodically start an AD-conversion and then just write OCR1A=ADC. In Arduino-speech you could do almost the same by writing analogWrite(analogRead(chan)/4) here you need to divide by 4 because in the default settings analogRead is 10bit wide but analogWrite only 8bit.
