One thing to note is that the oscillation frequency in this circuit is heavily dependent on the voltage source, so if you are using a battery, its important to calibrate right before you measure...
Hi, if im using 2n3904 instead for transistor, will the measurements be the same or do i have to adjust any values in the schematic to adjust for the difference in transistor values. Please. Thanks for this. Tia
Ludic, the source web page says that the resistors may be any value between 47 and 100 Ohms. What is the effect of using a lower value, or higher value, resistor from within this range? I would think that it would change the range of oscillation frequencies the device would operate in and, therefor, the range of inductance values that the device would be able to read. If I have this correctly, please do the math for us, to calculate the operational frequency ranges for the maximum and minimum resistor values and convert that to inductance ranges. Thank you.
Cool thanks for sharing, is there a point, I wonder at which the circuit will not oscillate in the larger range? for example have you tried 100s of MH or 1 Henry + ?
Hello, after checking one million times that I have done the right connections and checking and trying that transistors are ok it does not work. Once it is powered voltage goes steady DC just little below 160mV. I am using two 2N2222 transistors. I am measuring with an oscilloscope.
Every producing oscillation does not has a mathematic formula but can be completely arbitrary when voltages and component values are finding a random point of balance and then start to oscillate simply due a bad circuit design.
It doesn't work taking frequency from a nice digital multimeter Fluke, that is why you are using oscilloscope, a very sensitive one.I was thinking that instead you using a simple multimeter, why you are using oscilloscope for demonstration purposes??
Are you sure it is microhenry, not millihenry? Micro is common for Farads, for capacitors, but the inductors I have used in small circuits have been in the milli Henry range.
One thing to note is that the oscillation frequency in this circuit is heavily dependent on the voltage source, so if you are using a battery, its important to calibrate right before you measure...
where does the “50,000” in the formula comes from
Great nice work... i've learned alot with your videos...from the Philippines😁😀
Thank you 👍😊
Dear Mr Ludic: Excellent circuit! 👍Very instructive 👍
5:41 putting eyeglasses off - now i can see clearly ;-D
thx for making such inspiring and understandable vids!
Awesome video....Thx for educating u r viewrs.....
I like watching your videos. They are pretty interesting. What's more, it is easy to understand you :). Thanks !
😊👍✌
Best video on the subject!
Excellent video
Thanks
Very nice, good
well done
👍
Hi, if im using 2n3904 instead for transistor, will the measurements be the same or do i have to adjust any values in the schematic to adjust for the difference in transistor values. Please. Thanks for this. Tia
Hey, tis is now a really great idea! Ha, goood idea man!
✌
It would be helpful if you explain where the “50,000” in the formula comes from.
Do you happen to know the range of inductance this can measure? (I am trying to measure in the 15mh range). Thanks!
With a small audio amplifier and headphones a metal detector circuit is made.
Great nice work thanks
Ludic, the source web page says that the resistors may be any value between 47 and 100 Ohms. What is the effect of using a lower value, or higher value, resistor from within this range? I would think that it would change the range of oscillation frequencies the device would operate in and, therefor, the range of inductance values that the device would be able to read. If I have this correctly, please do the math for us, to calculate the operational frequency ranges for the maximum and minimum resistor values and convert that to inductance ranges. Thank you.
I recomment this, measuring from 1 pF to 100 mF at 1 % resolution
The LC100-a costs US$ 18.99 at Banggood
at best quality!
I have one of these and it seems to work great for everything BUT inductors. Have you had better luck than me with that?
Cool thanks for sharing, is there a point, I wonder at which the circuit will not oscillate in the larger range?
for example have you tried 100s of MH or 1 Henry + ?
I hace not tried
Great Job ! Is there a valid range for unknow inductors value ?
Nice
looks like mazilli zvs circuit but with bjts
Cool
Do the values of the resistors connected to the base have to be 56 ohms or would 47 ohm resistors work?
47 is ok
In the equation F=50000/L what the constant 50000 means?
Great
Hello, after checking one million times that I have done the right connections and checking and trying that transistors are ok it does not work. Once it is powered voltage goes steady DC just little below 160mV. I am using two 2N2222 transistors. I am measuring with an oscilloscope.
No worries, I had the probe in 10x, I am leaving the comment so others can be helped from my mistake. Sorry...
the upper resistor is 56 ohm or 5.6?
Could be anything 47 - 100 Ohms
I had made this circuit using BC548 but giving wrong result
You might have made some mistake. Please recheck or visit www.zen22142.zen.co.uk/Circuits/Testgear/inductance_meter.htm
Every producing oscillation does not has a mathematic formula but can be completely arbitrary when voltages and component values are finding a random point of balance and then start to oscillate simply due a bad circuit design.
Sir but i havn't osciloscope to measure it
please diy osclioscope
U can buy osciloscope kit with a low price i think 30$
Use multimeter
2:19
@@Not-C-418 do you know where to get one?
@@toddatwood4745
th-cam.com/video/x19kwG-wJRI/w-d-xo.html
It doesn't work taking frequency from a nice digital multimeter Fluke, that is why you are using oscilloscope, a very sensitive one.I was thinking that instead you using a simple multimeter, why you are using oscilloscope for demonstration purposes??
I tried to make it, but why my multimeter can't read it
It seems your multimeter can read square wave, but this is as like saw tooth waveform.
i did the circuit, yet not work.
just get the dc on the output
Are you sure it is microhenry, not millihenry? Micro is common for Farads, for capacitors, but the inductors I have used in small circuits have been in the milli Henry range.
Micro henry inductor ranges are very common in switching power supplies.
So to know the inductance you need an osciloscope? I call that the expensive way
Watch the video, you can also use multimeter