Your videos are so good and so clear. They demonstrate what all KZbin educational videos could and should be. I see you no longer create them, and I hope you are in good health and have such a great job that these videos aren't worth your time. But I am glad that these videos are still up on KZbin.

This is still the best DIY filter video on the web. Having only 125k views after 7 years is a shame. But thank you for creating it.

amazing explanation

Very good. I've been researching and this is the best I've come across. The app I want is to have laser beam interrupted by a swinging pendulum. That feeds into an Arduino to get times of swings. The output being binary One thing I picked up on is your comment on stray lights. That's given me the idea of a filter of the right colour on the detection side. 1. Are there reasons to use a combination op amp and comparator chip? 2. Is there hysteresis in the circuit? 3. If there's bounce on the output I presume I can use a low pass filter?

Im thinking that I could sync an ADF4351 to my GPSDO, set its output to 57.6 Mhz and then divide by 2.

Yeah try to push 100W through trimmer cap😂

very good, thanks

Great presentation. Thank you. What about slew rate at 14 Mhz ? What do I use for an op-amp ?

Amazing! Thank you so much for taking the time to do these videos.

What about capacitors type resistors types

Thank you for the info 👍👍

Not bad, but have you considered replacing the crystal in an exsiting TCXO? The cheap ones just seem to have an HC-49 package in them.

The single transistor Delta-Vbe trick is interesting, thanks for sharing!

Very helpful video... either for my English listening pratice and for make my own oscillator too !!! Thanks for it !!!

The most clear explanation I've ever seen, thanks! However it would be worth to tell a bit about the constellations.

I initially thought it would be due to the trace parasitic inductance from the 15V supply to the collector of the transistor which formed an LC oscillator with the collector-emitter parasitic capacitance. If all else would have failed I'd have added a ferrite bead around the pin of the base.

So Much Bnc Connectors

Yes indeed, who told diodes how to do trig haha. Very nice explanations. We can do wonders by cleverly connecting a few simple components

Brilliant thank you

Is there any way to make these filters have a sharper curve? There are some strong VDL2 blips on 136.7 MHz that overload the SDR, Meteor LRPT is much more affected as each time these blips appear the meteor demodulation loses sync. Or is there a way to make a notch filter with a similar design?

good

I don't really understand how the concept of ensuring that the series equivalent resistance being smaller than the internal resistance of the crystal degrades the high Q of the crystal? Why does that condition need to be met??

nice

What if the paths were filled with a conductive substance and a thermal camera looking at it from above would show the path of most current?

Is there a detailed schematic for this?

Hi, why coupling the oscilator with the capacitor and resistor divider and not directly ?

This is really cool, tank you!

Great video!

Do Sallen-Key active filters work at HF frequencies 3-30Mhz ?

Well, now I know that the AD633JN frol Aliexpress that I bought are fake, those only heat up and do nothing. Very helpful video.

Do you have suggestion what op amp ic that perform good with this circuit?

We can use this type of filter on tx as well?

Note: one doesn't absolutely need precision resistors - 1 trimpot used in the feedback loop of the rectifier opamp *or* one trimpot to adjust the input weights into the inverting adder is enough to balance out any error in the other resistor pair.

What’s the bandwidth of this mixer? What frequencies can it handle?

Is the plane made of PTFE?

I don’t think the explanation of the mixing in the beginning is really accurate. It’s rather mathematically involved specially in an analog environment.

Beautiful. But the coils are coupling. Place them in 90 degress to each other ...

Hi how can we apply this on gnss? lower band (from 1164 MHz to 1300 MHz) and the upper band (from 1559 MHz to 1610 MHz). Each band has multi channels.

This is very good! Thank you for taking the time to do this video you are a very good teacher!

Excellent! Thank you.

Your analogy starting around ~1:25 is one that would have confused me back when I was in school. Mainly the fact that you're using a digital device to describe analog behavior, and if when I was new to the topic it may not have been obvious why or where your analogy breaks down(Or I might not recognize it as an analogy and take it very literally), or even that you really intended to discuss analog signals and not digital. Just my 2 cents.

bro, you made this whole video, and your supposed example is utter trash which you showed for less than a minute. thumbs down, fraud.

your frequent smacking of your lips after finishing a sentence is an annoying attempt to portray confidence.

These are at the exact level I require. Thank you so much for taking the time.

Wow. I've been using this exact configuration for crystal oscillators for decades without ever really understanding it, & this is the first explanation I've ever seen that's ever made sense to me. Thank you so much!

why can't any of my profs just fucking say this. Good lord you make this easy. Well done.

hey your blog domain expired. move to blogspot

أين فيديوهاتك الحديثة

This video just started playing out of nowhere while i was replying to comments. I wansnt even watching anything to begin with. It’s wild because it’s exactly what I needed to know. Im building a radio. Right now im trying to amplify 4mhz active crystal and its not working. The crystal by itself is louder than adding a transistor or fet. I didn’t play around too much with bias and I didn’t do any filtering. I used an antenna and resistor or i used a transformer and antenna, I even just shorted it with antenna. I figure it should at least be louder than the crystal even if poorly implemented but maybe not. Another round of testing today. Maybe the chips im using can’t handle 4mhz but I didnt think that was particularly fast for a run of the mill semiconductor pulled from old monitors. Today ill try making my own oscillator I guess. Also would help if i had my 50mhz scope.