measuring inductance (0,4 uH-169 uH) via a frequency counter (principals/demo)

Proof of principle circuit. Principles of a circuit with which you can measure low inductance coils, going from 0,4 Micro Henry to 170 Micro Henry or more by measuring the frequency difference that they give opposite/in relation to a series coil. This combination (L-C) with a known and unknown inductance gives a certain frequency deviation. You need a frequency counter for this experiment. Succes on measurements for higher frequencies than approx 12 MHz/16 MHz depends on the oscillator that you use, the max. frequency generated by such an oscillator, and the properties from your oscilloscope. A better measuring frequency in this demo circuit COULD be 1 MHz or 2 MHz (not tested).My video shows only a (usable) demo circuit/concept that can be evaluated and developed more for lower inductance coils. By the way, perhaps higher frequencies etc. do not make much sense (I mean: get more critical, so no suggestion to do no experiments), because coils lower than 0,4 uH are often constructed specially and have to be calculated/made in exact dimensions and materials, thus with more sophistication. More electronic circuits are available in my books, on the Lulu website, author Ko Tilman. I use this circuit because the linearity from measuring the L-C combination/frequency/calculation/formula with a 1 transistor oscillator + frequency counter is not guaranteed, especially with L-C combis connected to the base of a bipolar transistor, but with this circuit above there is more guarantee that it works well.

[@radiofun232]

LINKS TO VIDEOS + SCHEMATICS ABOUT SINE WAVE RADIO OSCILLATORS Getting more insight in radio coils with a FET oscillator kzbin.info/www/bejne/gqOtiH-bZr2lias FET test oscillator with very good linearity (200 KHz-9 MHz) kzbin.info/www/bejne/hJiXap59e5ihbtE Testing IF coils on 455 KHz with a bipolar transistor oscillator kzbin.info/www/bejne/kIPWdWqmr82obMU FET test oscillator for frequencies between 340 KHz and 2 MHz kzbin.info/www/bejne/gGKZeWqhbLmWgLc Sine wave oscillator L-C on 15 KHz-20 KHz or more kzbin.info/www/bejne/rXysi2qjmNakjNE Variable sine wave oscillator schematic 380 Hz-19 KHz kzbin.info/www/bejne/ml7WhpyVl7d6hNE Wien bridge sine wave oscillator 500 Hz-40 KHz kzbin.info/www/bejne/mmmUiJyCaNJkmbc Sine wave oscillator (coil) 56 KHz-1,5 MHz kzbin.info/www/bejne/ZqnQnmBoft1_i6s Oscillator 140 KHz - 843 KHz or more with the LC coil on ground (emitter) kzbin.info/www/bejne/npy6YayLqZp4nqc FET oscillator 56 KHz- 1,5 MHz kzbin.info/www/bejne/q6Pdg6WNqr-Hjqs Local oscillator 1,3-4,2 MHz kzbin.info/www/bejne/f3KWfqill5iah6s 455 KC IF filter oscillator schematic (BFO) kzbin.info/www/bejne/enrId5VjiKugr80 Always working radio oscillator (schematic) kzbin.info/www/bejne/fHypYoiMrJ6co6c Test oscillator for coils 30 mH - 0,9 uH kzbin.info/www/bejne/gWPRnKSkp9x3bdE Oscillator for low supply voltages kzbin.info/www/bejne/aaXHnn6LjMmkaKs FET J310 Local oscillator (3,2 MHz - 13 MHz) kzbin.info/www/bejne/gYPckICjod6gh8U FET J310 Simplified local oscillator 1,2 MHz-11,5 MHz kzbin.info/www/bejne/aWmrcnhpbcuaqK8 FET J310 Local oscillator for 11-14 MHz and 23-27 MHz kzbin.info/www/bejne/kKrIiKSvZ6iBetU Local oscillator (VFO) for a (SW) Radio demo/schematic kzbin.info/www/bejne/pX2sp3-ZgMlkfMU SW radio VFO oscillator circuit kzbin.info/www/bejne/inrdi6KNqqaXeqs Playing with SW radio oscillators part 1 kzbin.info/www/bejne/nZyum3WhlJWkqa8 2 transistor superhet radio for strong local AM stations kzbin.info/www/bejne/e4qvp4Bnm5p_gKM + Why an oscillator? kzbin.info/www/bejne/d5nVpaadnNOSe7s + How to bring an oscillator in the right frequency band kzbin.info/www/bejne/bmbCYqChr7qlo5Y + Oscillation conditions kzbin.info/www/bejne/d5KqdaOomrKXg5o + Oscillation conditions part 2 kzbin.info/www/bejne/m5e6Z5WoZ5Z9mMU + Oscillators, how they can confuse you and disguise kzbin.info/www/bejne/iYLThaWDbtFjicU Green LED’s used as varicaps in a (VHF) oscillator kzbin.info/www/bejne/boq5hnunpMhkZ80 Dipmeter-search the resonance frequency kzbin.info/www/bejne/h4e3npx8l8tqfcU LED’s used as varicap’s in a SW oscillator kzbin.info/www/bejne/Z6Kvo4aGmK-KjJo Effect of temperature changes on a VFO kzbin.info/www/bejne/rqfTop-slNd0bMk Harmonics from a sine wave on a spectrum analyzer kzbin.info/www/bejne/b37anIyNmL-WZ7c Effects from tin plate on a VFO oscillator coil kzbin.info/www/bejne/pKK7fmqciMihZqs = Oscillator 26 MHz to test coils and crystals kzbin.info/www/bejne/qXWUiZWPlrlln8k = Crystal oscillator on 6.000000 MHz and 3,0-3,6 V kzbin.info/www/bejne/r4Spp2ttm8-dsM0 Oscillator (247 KHz - 303 KHz) made from dissected Ikea lamp kzbin.info/www/bejne/rpesoaqrmbt3l80 Sine wave oscillator J310 FET (33 MHz) works on stray inductance kzbin.info/www/bejne/hYO4ZKaHhpWbatk *Radio oscillator that works too good kzbin.info/www/bejne/sKWrmJePpctsfbs *VHF oscillator tunable by only a potentiometer/evaluation 2016 kzbin.info/www/bejne/e6q3gWd5pcqtaJo *Sine wave oscillator tunable by a potentiometer 28 MHz-43 MHz kzbin.info/www/bejne/gp2vf5SQl6uFr9k *VHF oscillator tunable by its working point (1 potm.) kzbin.info/www/bejne/Y6mzaadjgJKcrJI *VHF oscillator only with potentiometer 78-95 MHz kzbin.info/www/bejne/d37Zd6qdgMlmhrs *VHF oscillator where the L-C tank circuit plays a secondary role kzbin.info/www/bejne/onvGXoKpbNl2d6M Plotting a VHF oscillator on 50 MHz-110 MHz kzbin.info/www/bejne/fJPIqGCsi7Wbh9U Universal VHF oscillator 50 MHz - 110 MHz kzbin.info/www/bejne/g5i8pJSliJyhqNU + or * or = means a thematic series of video’s

[@radiofun232]

LINKS TO VIDEOS WITH SCHEMATICS ON MEASUREMENT TECHNIQUES & TESTS Analog frequency meter 45 Hz-19 KHz pt 1 kzbin.info/www/bejne/rJ6Ye5-vjNaUmZY Analog frequency meter 45 Hz-19 KHz pt 2 kzbin.info/www/bejne/nn_MnHV-ea-qnZY Test device to get insight in transformers and higher inductance coils kzbin.info/www/bejne/q2rWgZKYareZrNE Getting more insight in radio coils with a FET oscillator kzbin.info/www/bejne/gqOtiH-bZr2lias Device to test radio coils on their Q (quality factor) kzbin.info/www/bejne/foOQkqN_lL-egbc Experimental SWR (standing wave ratio) meter on 27 MHz kzbin.info/www/bejne/e6OsgqCIeaZnndE RF absorption meter demo + schematic kzbin.info/www/bejne/nIDRnayLZ7afrck Inductance measurement 1,2 uH - 180 uH + Q test kzbin.info/www/bejne/lZqnpaBues2FiMk Test oscillator sine wave with very good linearity 200 KHz-9 MHz kzbin.info/www/bejne/hJiXap59e5ihbtE The easiest way to test an IF can on 455 KHz kzbin.info/www/bejne/rKqriIiqaLqtitU Radio coils and dipmeter demo kzbin.info/www/bejne/nWe0iKaCbriBsLs Radio coils, properties, basics, examples kzbin.info/www/bejne/iKDMZaSipMaojKc Testing IF coils on 455 KHz with an oscillator kzbin.info/www/bejne/kIPWdWqmr82obMU What do you need for an electronic lab? kzbin.info/www/bejne/rGaTZJWjrtJ2jdk How to make a precision analog voltmeter part 1 kzbin.info/www/bejne/ppfMZoFjp9CGbsU How to make a precision analog voltmeter part 2 kzbin.info/www/bejne/a3XOYoGDr5J_h9U How to make capacitors from 1-300 pF and measure them kzbin.info/www/bejne/aqOnZX1ooLtra5Y Oscilloscope: how to make a very basic one kzbin.info/www/bejne/aoeWeoueiaukf68 How to make a 455 KHz IF filter yourself and wobbulator it kzbin.info/www/bejne/hmTdq6icbtVrnqs What to do with broken analog voltmeters? kzbin.info/www/bejne/jommloOlZb98nM0 Test oscillator for coils kzbin.info/www/bejne/gWPRnKSkp9x3bdE Measuring inductance (0,4 uH-169 uH) via a frequency counter kzbin.info/www/bejne/e6nMnKiodrZ-prs How to make a shunt kzbin.info/www/bejne/fH-YaopviKyiq5Y Prevent transistor leads from breaking kzbin.info/www/bejne/n3bIZGqlr5mnrdk Testing IF cans/how to find out their properties kzbin.info/www/bejne/noC2g3yAn62opKs Measuring the health of a N-MOSFET with a Ohms-Voltmeter kzbin.info/www/bejne/mYPXhWiZlMeei6s Electronic effects made visible kzbin.info/www/bejne/lZeYpIaFepicoMU Developing a precision capacitance meter kzbin.info/www/bejne/p5nconuhbdyLgNU Passive diode testing, part 1 kzbin.info/www/bejne/e3qTXpmgYpJ9oM0 Passive diode testing, part 2 kzbin.info/www/bejne/pXyslJWrl8aIjdk Silly MOSFET testing kzbin.info/www/bejne/h3LZpo2On7WBgq8 Diodes, common info kzbin.info/www/bejne/qpCuq6eumLGLo8U Digital frequency meter made from a radio with a digital display kzbin.info/www/bejne/a37dlX2IZp6Gbbs N-MOSFET (power type) tester (passive) kzbin.info/www/bejne/qmOYoqqsfal3jqc IF 455 KHz filter test with a wobbulator kzbin.info/www/bejne/maPJfJJ6nLiZfdU Test from a 455 KHz IF filter (oscillator) kzbin.info/www/bejne/a6jYeaB-g6qGpbs Extended scale precision voltmeter pt 1 kzbin.info/www/bejne/Y6vCm2eDmNF2is0 Extended scale precision voltmeter pt 2 kzbin.info/www/bejne/nHSUgoOVa7Sfd68 Wheatstone bridge demonstration circuit kzbin.info/www/bejne/j2SQfpufoZaosLs How to figure out an unknown transformer, part 1 kzbin.info/www/bejne/mZarlpJmntqblbs How to figure out an unknown transformer, part 2 kzbin.info/www/bejne/f3W5ZmZmm7KSpa8 Dipmeter: search the resonance frequency kzbin.info/www/bejne/h4e3npx8l8tqfcU Inside the Ferraris meter kzbin.info/www/bejne/n5DIlWOinN-ZoNk Do audio capacitors have a certain sound? Part 1 kzbin.info/www/bejne/pHnXeppjZamEgrc Do audio capacitors have a certain sound? Part 2 kzbin.info/www/bejne/ap_cnYKqiKaHhs0 Do audio capacitors have a certain sound? Part 3 kzbin.info/www/bejne/qJXTpJ2sjttnrck How to use a frequency counter, part 1 kzbin.info/www/bejne/ZqrJemioh7tmhs0 How to use a frequency counter, part 2 kzbin.info/www/bejne/aWG2oKqmqptnm8U Effects from coupling capacitors in audio circuits kzbin.info/www/bejne/m3eblmB8otl3npY How to measure AC current kzbin.info/www/bejne/hoizoqNprK2ciZY Testing PVC tape on high voltage kzbin.info/www/bejne/iKjQcqWcd7qWbtE Integrator and differentiator circuit, sound effect kzbin.info/www/bejne/hXymoXearNebfbs how to test switches on high currents kzbin.info/www/bejne/b6PYpGyLo9N_bq8 Inductance meter 0,4 uH-170uH for radio coils kzbin.info/www/bejne/innZdqSJdrB3bLM Measuring the resonance of a quartz crystal kzbin.info/www/bejne/rKeViZagnMaSjMU MOSFET fundamentals (static test) kzbin.info/www/bejne/j4apaJWtprN-aJo Inductance meter 1mH-100mH schematic kzbin.info/www/bejne/rJqTZWSMZdSciJY Effect from clouds on a solar panel kzbin.info/www/bejne/i5ObeGt7lK6Ib9E Radiofun 232 on You tube, all channel info and links kzbin.info/www/bejne/rpPKgmuKaNSknpY My books are on the website from Lulu, search for author Ko Tilman

[@MrElectrosock]

I have thought about building a capacity gauge and inductance, with a microcontroller and a program under linux to do the presentacion in PC. At first I thought calculate the inductance measuring th discharge time voltage of the coil. But it seems an interesting way to calculate your inductance with frequency of the tank circuit oscillator and give me the impresion that it is more accurate. Thanks for you video.

[@radiofun232]

+Angel Jimenez It is, indeed, very accurate and even the slightest frequency variations (due to capacitive or inductive influences) are visible.

[@MrElectrosock]

+radiofun232 Thank you very much for the info, I'll get to work with this project, very interesting all your electronic RF channel. Thank you.

[@Mushketer888]

I always wondered which inductance values are the best as i calculated you make coils for LC tank with 200-700pF am i right? with these capacitor values there is better Q factor or it depends on coil's resistance? maybe you could say something in another video about Q factor

[@radiofun232]

Perhaps my recent video can help you. The Q factor can be calculated and is an issue that takes a long time to tell. Perhaps later, I have to study this (formula's) to make a useful video. High Q =low loss so high quality insulation materials to make the winding on the core (glass,pvc,moisture free cardboard), good spacing (0,1 cm MW - 0,3 cm SW), no skin effect, General info in my video from 13 feb 2015 and in my book on the Lulu website (payed content).

[@Mushketer888]

Thanks!

[@flyingfox8072]

I think The oscillator shown should have a capacitor connected between base and ground. Pl correct me if i am wrong

[@radiofun232]

My advice: repeat the experiment and try it. All component values are showed.

[@mountainflumehobbyist3187]

Hey radio fun i strongly admire your videos and was wondering if you could make a 3v-240v DC motor control circuit

[@radiofun232]

Thanks. The subject that you propose is (sorry) a subject where my knowledge and experience is (more or less) zero. The only thing I know is that a series resistor (or circuits like that) do not work properly, because the DC motor looses its power. Perhaps someone on another KZbin channel can help you.

[@mountainflumehobbyist3187]

Okay that's a shame i wanted to make an environmentally safe go kart using a large DC motor but i only need to control it but other than that your videos are just so sophisticated and imformative i have learnt so much watching your videos and just wanted to say.... Thanks

[@fatnindja]

Hi, can you help me with this circuit. I built it but it doesn't seem to oscillate or my frequency meter doesn't see it?! The circuit is consuming 8.4mA at 12.2V. Coil is 30 turns like yours, cap is 330pF. 150 ohm is 220, 270 ohm is 220, pot is 22k, 1k is 2.2k, transistor is BD140 ... what could be the problem? I connect the frequency meter directly or through 70pF but it doesn't show frequency but it does show some reading if i short CE of the transistor, so I guess it is not oscillating. Any ideas?

[@radiofun232]

I will study your question and give a first reaction. Mail me on [e-mail] and send me pictures and a drawing of what you have made, I will try to help you.

[@radiofun232]

Question: do you want to make an oscillator and/or on what frequency? Could be that this circuit is too experimental and there are many other circuits on my YT channel that perhaps will fit to what you want to make.

[@fatnindja]

@@radiofun232 I try to make the experiment from the video, because I would probably need to measure some low inductance coils. My first goal was to make the circuit and see the frequency of oscillation but it didn't oscillate. I played with it some more and figured out that the frequency meter does see signals through 70pf, so maybe it is the circuit failing to oscillate. As I said before I didn't put the exact resistors you suggest but I can do it if that's the problem. I can post you pictures tomorrow because it is 5AM here.

[@radiofun232]

@@fatnindja OK, good, I am interested.

[@radiofun232]

@@fatnindja You can do your experiment in fact with any HF oscillator. The following circuit works best for that purpose. It has a low parasitic capacitance on its input and is linear kzbin.info/www/bejne/hJiXap59e5ihbtE

[@fingerzmojaji]

I need a 0.6uH inductor that can take 400A how did you make it?

[@radiofun232]

Sorry, I don't know that. But in your situation: 0,6 uH is a very low value. 400 A means an extreme current. In such a situation I would use (only an advice..., never practiced it!): 10 turns of copper 4 mm wire (properly insulated) at a ferrite rod of 1 cm diameter for a first experiment. No guarantee for succes. Or use it without that ferrite rod. A Shortwave coil of 0,6 uH consists of approx. 5 windings diameter 1.8 cm without any core.

[@radiofun232]

Please read my adapted comment 21 july 2018.

[@fingerzmojaji]

Thank you very much ill post my feedback during the week.

[@radiofun232]

I am interested, where do you need a coil of 0,6 uH at 400 Ampère?

[@fingerzmojaji]

I want to build a car battery welding machine. I've seen people here on youtube welding with two to three batteries in series, I want to weld with just one 12V battery so I need the coil for the compact DC-DC converter I'm trying to build. I don't know if it will work.

[@Mushketer888]

Big thanks for this!

[@radiofun232]

You are welcome.

[@Mushketer888]

by the way i saw (and soldered) LC meter which uses Comparator as reference frequency Maybe it will give you some ideas And microcontroller is counting frequency and calculates value

[@Mushketer888]

and if you dont want to use MCU i think frequency counter is possible to make with 7400 series (counter,oscillator,divider etc) maybe it is even possible to somehow calculate value with such logic elements it would be very interesting

[@radiofun232]

Ilja Lebedevs Thanks for your comments, idea's and suggestions. The point is that I want to develop a very simple uH meter for my KZbin viewers, in the low uH range. I did a lot of experiments in the past and know how to develop such a thing, but want to make it more easy, a very simple circuit e.g. with a bridge (wheatstone like or so) and a shottkey or germanium diode, uA meter and a potentiometer, etc etc. Problem is as always the very low values like 0,4 uH or so, their inductance is so low that they don't give visible effects on meters etc. So then it comes to a counter, etc etc, but that is not what I want. Anyway: thanks for your attribution!

[@fredbilindula700]

How test ics

[@radiofun232]

Fred Bilindula There is no general way to test IC's, they are all specific.The best test: use them the way they must be used given a certain schematic and see how they work and/or adapt the components..