#361

Episode 361
inductance in a 50ohm load
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[@SergioTemblar]

You are going right to the point. Lots of info in a short video. Good job. Besides, as a francophone learning english, it is important for me to find high quality material like yours. Many thanks. 🙂

[@lupuszzz]

You are mostly measuring the electrical equivalent of the inductances of the carbon layer inside the resistor (it's a coil) and the the wires. Additionally the external wires and the caps at the ends of the resitor are two different capacitors, which react different at different frequencies.... This assumption could be used as starting point for moderate HF frequencies. When frequencies increase or when the resistor is soldered onto a board, things get even weirder. For understanding electrical/magnetical fields, components and schematics at high frequencies, it is highly recommended to study them in theory first. Even with a degree, many fail to fully understanding HF. I think a good approach is to make predictions first, calculate the result based on your asaumptions, measure the reality and correct your picture until it fits perfectly.

[@PapasDino]

Your video set on the nanoVNA was the hot topic at ham club lunch today; several guys are purchasing (I ordered mine this a.m.!).

[@ptarsob]

An excellent and very didactic video. Congratulations!

[@IMSAIGuy]

Thank you

[@SlamminGraham]

One nit-pick: Increasing frequency does not "add" inductance. The inductance is always there. The effect of the inductance is just larger at higher frequencies.

[@IMSAIGuy]

true

[@krisraps]

If You Cal With An Addapter Or SOme Addapter Wire, Make Sure You Leave It When Using The VNA After Because Its Calibrated With It..

[@pentachronic]

Useful video. Thanks.

[@h.sapienstechnologicus8865]

gr8! Any idea of board specs i could solder these little resistors onto?

[@youngsanger]

The applications outrun that silly user interface. We need to dump the display and connect Nano directly to our chromebooks via USB.

[@Desert-edDave]

Also isn't there a potential inductive component to resistors that are wire wound and not carbon film? :)

[@IMSAIGuy]

absolutely!

[@armmargret1970]

How did you calibrate for this demo? Changing the frequency range makes a recalibration necessary to get acurate results.

[@IMSAIGuy]

The VNA takes the frequency range you have set and takes 101 measurements over that span there by calibrating the entire frequency range.

[@falsedragon33]

And causes it to interpolate those points. Far better to calibrate it every time.

[@bobflyer4346]

First, thanks for the video. New to the VNA. Question. Inductance of wire coils measurement when using say a CW or fixed frequency. Is the results say withing x%. Same question on Capacitor measurement. Wish to measure coils and caps on unit. Don't have a lcr meter. I notice on your example in the upper right the nh inductance varies, perhaps due to sweeping the frequencies? If you measured at a fixed frequency is the inductance close in accuracy?

[@IMSAIGuy]

yes you can use this to measure L or C at a fixed frequency but it won't have much of a range or accuracy as an LCR meter. A $6 component tester would be better: www.banggood.com/LCR-T4-12864-LCD-Graphical-Transistor-Tester-Resistance-Capacitance-ESR-SCR-Meter-p-1311439.html?gmcCountry=US&currency=USD&createTmp=1&ad_id=411455834827&gclid=Cj0KCQjwncT1BRDhARIsAOQF9LkeIOeL84wnFGsV69PtspwOm_fsDBqXt9t_PGgm3CUPm7J26HBoXvgaAjyBEALw_wcB&cur_warehouse=CN

[@bobflyer4346]

@@IMSAIGuy Thanks

[@ovalwingnut]

Really interesting. Thank you 👍😁 SUBBED✔

[@jeffdwyer6105]

You forgot that carbon film resistors have spirals within (like a coil) so you will always have a little inductance , You blew the test by changing to the surface component .

[@SixWildKids]

Not sure about that. Isn't that wire wound resistors?

[@galileo_rs]

Link to the mentioned channel, W28W callsign?

[@IMSAIGuy]

kzbin.info

[@galileo_rs]

@@IMSAIGuy Thanks, I guess I missed that video from Alan.