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lm317 is not that stable as a CC source. Unfortunately most CC sources are quite complex, requiring multiple components. One choice is to use an LM334 in the temperature compensated configuration shown. However, for its simplicity, this circuit is still quite good

..that's easy for you to say!

Da

Wow nice electronic project I will love to have this thank you so much

Como ajustas el circuito solo con las punzas separadas o usas una resistencia en serie

Thanks Lau. You had a great idea.

Thank you it is a good job

I'm not sure why but I have it set to 100ma and I can't get it to zero on mv with the probes shorted. I get around 25mv.

What is the current needed for the supply?

VERY GOOD

Can .add hz and duty cell .. ?? Indicted

What else can be used without this ic ic number..

Hello nice work !!!! It is posible to make one with 4 in and 4 outputs , Oszilloscope ?? That would be very cool Thanks

How to made underground 3d imaging analyzer detector sir.... 🤗

Сделал уникальный прототип осциллографа без микроконтроллеров, зацените):

Just noticed: I would strongly recommend adding a resistor in series with the pot (to limit max setting), for safety. Without it, if you build this, and don't know or you have the pot set to the minimum by accident, it will FRY the pot, and may BLOW out your meter (usually the meter amp range fuse). An 18Ω or 20Ω would do; but not more than 33Ω. A 33Ω would limit max setting to ~104mA or lower, with 5% (or 10%) resistors, you might not be able get 100mA output with the pot cranked, depending... Below 18Ω will not eliminate the potential overload condition: 18Ω is the minimum 'IF' the pot is a 100Ω 1/2W {500mW) potentiometer. Any lower and it will overload the pot at certain settings (too much current through the pot). Or, as in this case of NO series 'safety' resistor (as in this design), if the pot is set less than 18Ω, then the pot AND the circuit will overload... 100mA is used for this type of project simply because it makes the math easy: 'mV reading X 10 IS your mΩ reading' You could use any fixed mA setting, but then you would need a calculator to decipher any of your readings... Many other combinations of pot and resistor values can be used for this circuit: The pot and 20Ω resistor is simply creating a precise 12.5Ω resistor between pin 1 & 2 of the LM317 (adjustable for exact calibration). [The pot is at about 33.3Ω at the calibrated 100mA output]. You could use a fixed 12.5Ω precision resistor. You could also use a fixed 33Ω in parallel with the 20Ω resistor (and no pot). A 15Ω fixed resistor (instead of 20Ω) and a pot (or fixed resistor) tuned to around 75Ω also does the same. (and twice as fine adjustment. Although a 100Ω 25 turn pot is plenty fine, as in this (his) design... ANY* combination that gives you 12.5Ω total to the IC will work... *[don't exceed 42Ω in place of the 20Ω or this pot (if using a 100Ω 1/2W pot) will be carrying too much current]. Mr K L

Those are 'Kelvin clips'. He forgot to put them in the materials list. They are the key to accurate measurement of the DUT (Device Under Test). Without them, you could get false readings because of the milliohms of the clip connections to the DUT. DYI work-around is to use separate alligator leads to supply the test current, and to read the voltage drop. Just be sure the clips are independently contacting the DUT and absolutely DON'T touch each other! Or you can just put alligator clips on the current source, and just use the meter probes to read the voltage - Just make sure you ONLY touch the part/part's leads, and do not touch the supply clips at all. [It will not damage anything if they touch, you will just get a false reading while they are touching each other]. They Kelvin clips are optional if you just insure you have 4 independent contact points, two per each 'side'. The Kelvin clips are more of a convenience than a necessity... Also, if you measure a very low resistance resistor with wire leads, you will probably want to measure at about the estimated installed length of the leads... Remember, the leads themselves have some resistance. [clip the 'current input' leads to the point at which it will be soldered when installed, and probe the voltage anywhere outboard of that. 24ga wire has ~26mΩ per foot. That would be ~5mΩ if a part has two 1" leads when you measure it]. Insignificant if you're measuring say a 0.22Ω emitter resistor, but important if you are doing something around 50mΩ or less; calibrating instruments; or testing the accuracy of your tester. Keep this in mind if you for instance, chassis mount 'eared' power resistors (which should be greased and mounted to meet the marked power rating!), that you allow for the lead resistance from your board/chassis to the resistors... [For example, a 0.22Ω resistor mounted 6" away with 24ga hookup wire would present over 0.24Ω overall, and with 12" leads would read over 0.27Ω] Mr K L

I have to say I get excited when you make a new video 'Lao' because there always so interesting protects. Love your stuff a fan from Ireland 🇮🇪 🤣💚🙏🏼👍👍

Hi . Can the esr of the capacitor be tested with this circuit?

SHOW DE BOLA

Tks!!!! I make this milliohmmeter and is very accurate! I mensure 0.035R with precision! Very simple project! Very good.

Sir I want this

Sir please send me this project

280 pump is this pump 12V or 5v

Iv made this before from you channel. Thank you 👍🇮🇪💚🙏🏼

Love this tip 👍🇮🇪💚🙏🏼

非常好背景音樂,教學視頻更易吸收👍

you should have mentioned that video is not in english ! when the title is in engglish, without mentioning the language of video, it is missleading..... video disliked..... i spared you the report since i was really interested and i value those who share their knowledge. please consider mentioning the language of video !

It's ghs

Oscilloscope circuit for TV or monitor

Is there any possibility to make voltage range upto 400v?

Can't read the English subtitles even when phone screen is magnified. Wish this video was in English, would be a needed circuit.

amigo pode ser feito com (STM32G070 RBT6) friend can be done with (STM32G070 RBT6)

garbage！

Can we make it without using Arduino mini

Funny shit! can you add a Zigbee module to it, so I can connect it to Domoticz?

How did you set your oscilloscope?

How did you set your oscilloscope?

This is a good representation of a pcb that is good for smd components.....I mean for testing them...Just an awesome device....thanks for the video..

thank you,,,,,

Can I adjust the trimer to get 2.5 mA? with this circuit?, I need this to be 4V output and 2.5mA limited.

Hallo can someone please help me to understand. Do you get firefox addon to translated

English please

Anyone allergic to glass fiber? I am very sensitive to it and cutting PCB is always a great pain for me.....Watching this video makes me feel itchy.

thanks for you . Please you send to me the source code and all details of this video

I don't understand, how can you make a constant current source based on LM317? You can set up an output voltage, but the current will fluctuate in responce to the temperature changes, oxidation in contacts and the value of the resistor to be measured. I can see it as a probe (a short circuit yes/no tester) rather than an accurate miniresistence meter. It will of course show some value in the resistance, but I don't believe you can trust it. To achieve a genuine constant current you will have to complicate the circuit somewhat. I can't see it done without a comparator (OPAMP) which together with a reference device and a high accuracy setting resistor forcing the current into total stability.

你是老劉嗎?😅

Nice work Thank you

Hello i created it it is nice but after some uses it got out of range and i had to adjust it again to 100mA. Is this normal ? Thanks.

Great video of you home brewing a power meter. Wow. I liked your techniques for building it. I see the various tools you used how to carve the box to fit. Do you have a schematic and parts list and possible instructions on how to build what you built? I like to see you build other projects. I can see that you have good experience at home brewing projects. Thanks for showing us!