#1616

[@Hellhound604]

Worked in the RF-industry for 40+ years, but every now and then I still learn new things, or get reminded of elementary things that I have forgotten. This video is one of those… thanks for triggering those old and diseased brain-cells of mine.👍👍👍👍

[@DeezNutz-ce5se]

How do I get into a career like that?

[@bayareapianist]

​@@DeezNutz-ce5seyou have to be very passionate about learning this stuff and then get lucky and a manager recognize your passionate and hires you.

[@DeezNutz-ce5se]

@@bayareapianist oh great. Not happening where I live. Geuss I'll have to move. Cheers

[@richardgray8593]

I like how you pick a bite-sized subject and do a short instructional video on it. I've got zero experience with spectrum analysers, so it's nice to see one in action.

[@IMSAIGuy]

I did a two part beginners guide to spectrum analyzer: kzbin.info/www/bejne/kJaXh2mHpZaggZosi=6iNQ7EtpfV7gCxZU

[@richardgray8593]

@@IMSAIGuy Thank. I'll check it out.

[@AnalogueGround]

Excellent video. In my 50+ years of electronics, I’ve never thought of the quartz crystal in any great detail.

[@kennywang6222]

Awesome teaching material without scary mathematical formulas. Thank you.

[@justinkovacik9436]

Thank you that was very educational. Feeds my hunger to know how things work

[@tonyfremont]

Lead inductance really matters. All passives are really just some combination of inductance, capacitance and resistance. ;-)

[@georgesampson4714]

That was a pretty good one, video I mean. I read about this stuff but having the equipment to actually perform experiments makes it come alive.

[@ats89117]

The name of the model is BVD or Butterworth Van Dyke. It would have been interesting to show the phase plot where it is common for the response to be inductive between the resonance and anti resonance frequencies while being almost purely capacitive away from the resonance and anti resonance peaks. PZT transducers have the same type of response. Being made of a ceramic mix, they are not nearly as consistent as quartz, but they have much greater sensitivity, so they quickly replaced quartz in early sonar transducers...

[@__--JY-Moe--__]

did I hear breakfast! world renouned Van Dyke Freench Toast! Mmm yummy!🐒

[@raylowe3324]

Great video. Back in the early 1980's, I built an audio filter based on the electrical equivilent schematic of a crystal. It had a peak at 700 hzs and a notch at 1600 hzs. The notch was caused by the parallel equivalent circuit.

[@jagmarc]

I vaguely remember a tuneable crystal used at the AM detector , used as a sharp notch filter , on some government quality communication receivers from WW2 until a few decades ago

[@egbertgroot2737]

Another mystery demistified in my life! Thx

[@jagmarc]

What's so clever about Xtals is how they assemble a group of different ones together and they make up a precision narrowband pass filter. Say at 9 MHz with 2.4 kHz width. And another grouping makes up a 9 MHz with 300 Hz bandwidth. Amazing, before digital radio

[@tonyfremont]

I've done exactly as you describe. I built a 75m receiver on a big breadboard and used a crystal filter network to act as a narrow filter and using the same frequency crystal injected to do a direct conversion and detect the LSB. It was kinda haphazardly hokey, but it did work surprisingly well.

[@jagmarc]

Surprisingly good result with just injecting into the last stage's non linearity , from crystal-based BFO with varicap clarifier. I guess that's how you did it or did you use a proper balanced demodulator?

[@IMSAIGuy]

here is my video on xtal filter design: kzbin.info/www/bejne/aaa1cmSma7SiqqMsi=4-A0FAeEWyXVfOyN

[@paullavender6227]

Great video, thank you. It left me wanting to grab my cheap little SA and have a play.

[@thomasmaughan4798]

I did this with a Keysight oscilloscope that has the tracking signal generator built in.

[@hubercats]

Very nice presentation. Thank you!

[@andymouse]

Fascinating tutorial !...cheers.

[@bobdoritique7347]

Merci for this video. Very well explained.

[@dimBulb5]

Great job! Very helpful !

[@willthecat3861]

Just for the record... the actual quartz crystal, inside the can, and mounted between two plates, is more analogous to a pane of glass. The quartz crystal is greater than 100 times thinner than it is wide, or long It could be 6 mm wide, and 10 millimeter long... and yet be only 10 micrometers thick... that's hardly block shaped, IMO.

[@rfburns5601]

Focus?............Bofus? Hah! Always remember to adjust the output tank on your pierce oscillator above the series resonant point of the crystal, so that the output drops by about 10%. Else your oscillator will squegg out!

[@jagmarc]

sound advice. to do with phase. I know someone with his transceiver, he'd tweaked up every screw for "maximum output". Started squegging or something when it got hot! Not sure exactly was 40 years ago

[@thomasmaughan4798]

Yay, HP 35s calculator.

[@magicsmokeblog]

I love that part too, somehow, i feel it would be perfect if he was using an HP 15C.

[@IMSAIGuy]

I had the 11C 12C 15C and 16C.

[@thomasmaughan4798]

@@IMSAIGuy I had every one except the fabulously expensive HP65, the one astronauts took into space. My favorite was HP-41c and I really don't remember why I got rid of it. Needed money I suppose. I bought the HP-71b it's a beauty but it doesn't do RPN, it is a little handheld computer. It doesn't get much use but it sits on my computer next to a TI that gets even less use.

[@IMSAIGuy]

@@thomasmaughan4798 You can't name one I have not had. I had a massive collection once but sold it off.

[@glenncummings1326]

@@magicsmokeblog HP is reintroducing one.

[@R50_J0]

Good.

[@t1d100]

At 9:30, you combine the series LC with the parallel LC. In doing so, you connected the parallel C in front of the series C. This places the influence of the series C in the parallel circuit. I would have expected the parallel C to be connected between the series C and the L. Why is your method correct and my method incorrect? Is it that the series C influences the parallel C regardless of the attachments point, because, when combined, they become just one circuit? Please and thank you. I am a self-taught hobbyist with significant knowledge gaps from only studying what interests me.

[@IMSAIGuy]

rfic.eecs.berkeley.edu/~niknejad/ee242/pdf/eecs242_lect25_xtal.pdf

[@d942yd42]

Phase!

[@byronwatkins2565]

Actually, the usage of "series resonance" and "parallel resonance" is pretty close. Below resonance a series combination has capacitive (leading) impedance and above resonance it has inductive (lagging) impedance; at resonance its impedance is minimum and in phase. Then, above the series resonance, the equivalent inductance can form another resonance with the parallel capacitance. This parallel combination has maximum, in-phase impedance at resonance. The ONLY trait that is different is that neither the series resonance nor the parallel resonance can be modeled in detail as a separate circuit with constant L and C.

[@mr1enrollment]

reactance

[@SerenityMae11]

IMSAI guy meet Mr Focus Button. Mr Focus Button meet IMSAI guy.

[@jonathanlister5644]

Do you know what you are talking about?

[@IMSAIGuy]

I've got no clue. but here are people that do: rfic.eecs.berkeley.edu/~niknejad/ee242/pdf/eecs242_lect25_xtal.pdf