All You Need To KNOW About Potentiometers To FIX Stuff! How They work tutorial How To Repair

Potentiometers are very common components in analog electronic devices, let's have a look at how to understand the component markings, what commonly goes wrong with them, and how to repair them.

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TEST METERS
ANENG AN8009 MULITIMETER
KAIWEETS HT118E MULTIMETER
VC480C+ MILLIOHM METER
MESR-100 ESR METER
XC6013L CAPACITOR METER

TM-902C TEMPERATURE METER
LCR-T4 COMPONENT ANALYZER
FNB58 USB ANALYZER
PCI POST ANALYZER
TL460S PLUS PCI_E ANALYZER
TOOLTOP ET120MC2 SCOPE
FNIRSI 1014D SCOPE
NPS3010W 30V 10A PSU
T12 STATION WITH M8 9501 HANDLE
M8 9501 HANDLE
YIHUA 982 Soldering Station C210/C245
FNIRSI HS-02 PORTABLE SOLDERING C210/C245
QUICK 861DW
PROS'KIT SS-331H

INFIRAY P2 PRO IR CAMERA + MACRO LENS
TOOLTOP ET13S THERMAL CAMERA METER
ET13S MACRO LENS
OPTICAL MICROSCOPE
TOMLOV TM4K AF FLEX
TL866 II+ PROGRAMMER
CH341 PROGRAMMER
NC-559-ASM FLUX

DESOLDER BRAID (I use size 8045)
HX-T100 SOLDER (0.6MM)
ESD-11 TWEEZERS

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Thank you
Richard

[Beekaert]

Hello Richard. Usually logarithmic potentiometers are used in audio applications. That is why there is also an "A" for Audio on the potentiometer. This is a little tip to recognize a potentiometer linear or logarithmic. I try to remember from my school days that the "B" stands for the linear type as "Balanced". Still nice to watch your videos again and also quite educational. Please continue with this, good learning experience and certainly a useful tool to learn how to detect and repair errors, although every technician has developed his own method, there is always something to learn from someone else. Greetings from Belgium. Andy.

[Beekaert]

Hi Richard. Just a little side note. There are also potentiometers on the market that are equipped with a small switch at the back. These are usually used in portable radios to turn the unit on and off and also to adjust the volume with the same button. These potentiometers are usually logarithmic. Still an instructive video for novice electrical engineers among us. Thanks GRTS Andy.

[andymouse]

A Potentiometer is really a variable potential divider and is a 3 pin device however by attaching the wiper to one end and forming a 2 pin device you now have a true 'variable resistor' or rather a 'Rheostat'. Regarding log and lin Pots the reason that in audio we use log for volume or signal level is that audio systems such as the human ear perceive audio volume asLogarithmic. Couple of bits of useless info !....cheers.

[Coolman]

I was actually hoping you would make a vid on pots.. thank you!

[FS.DJParty]

Thank you. This was extremely helpful. I have some scratchy pots and was looking for ways to clean them. I would prefer that to replacing them. I too am a DJ. Rule #1 is no liquids near Mixer or amps. It eliminates so many problems. I even make my clients and their guests put drinks down before coming up to talk to me. Most totally get it right away, i just point at their drink and then at the power cords. Some you may have to tell them but either way works and keeps equipment safe.

[nonsuch]

Just a little additional info. As well as A for "logarithmic" and B for "linear", if you have a pot with a C before the numbers (i.e. C50K), it means "counter clockwise" and if you see a W before the numbers (i.e. W50K), it means it has a "center detent". C and W just applies to circular potentiometers, not faders which only use A and B. If a fader has a center detent, it's usually just up to the manufacturers and sellers to list it as so and/or may have an additional part number for reference.

[gordslater]

I think this vid has a variable potential and you may meet some resistance :)

[edfx]

Is it possible to rebuild carbon track in any way? I have an irreplaceable car throttle position potentiometer.

[davet]

One other small point . There is a viscous lubricant in spindle which when you turn up the volume on an amp helps with tactile feel . If you clean with appropriate cleaner it stops the crackle but the pot then moves loosely around because the cleaner has removed the grease from the spindle. Not a problem for me but audiophile types are obsessed with the feel of equipment.

[Sydney]

Well you flirting with potentiometers was more interesting than I expected it to be :)

[vaccarioou]

Interesting but also worth mentioning lubrication - too much switch cleaner cleans the track but removes grease on the shaft used to provide smooth feel when turning. You can get remove and re-grease the shaft with appropriate lube.

[acdnrg]

I get linear faders and pots: The longer the distance, the higher the resistance. Just like wires. But how do log faders and pots work? Is there a different material being used which has resistance related to distance in a non linear fashion? What is it then?

[ika]

Great video. I literally started out not knowing anything about Pots and have a great understanding now because of you. I do have a tricky situation though. I'm trying to replace the contrast Pots on an old tv and it's dual 20k 1k B. I can't find any with that combination. Have any suggestions?

[jimnicosia]

You can use them to find out the unknown value burned out resistors by substitution.

[tubeDude]

At 19:30 WRONG! Using *DeoxIT Fader F5* WILL repair it unless the carbon film is torn!

[pyrox]

I messed up a potentiometer by putting a bit too much contact spray in it. Now it's completely loose and really does not feel nice anymore. Would you know if it's possible to make them feel good again by maybe putting some fat in them or vaseline?
Would be very useful for me.

[anthonydenn]

Great video Richard. It's interesting looking at one of the log pots you tested, it had a totally uniform looking carbon track (Width and height wise). But it obviously measured as a log pot would.
I wonder what the process is that they do to the carbon track to make it logarithmic. How do they make it more or less resistant without altering the width or the height of the track.

[Yquan]

Question to the experts in the comments: I have a old Fujitsu siemen's speaker system and i recall having trouble turning it on, sometimes it did, sometimes it didn't and i had to fiddle with the potentiometer and get lucky it turned on. Now i am trying to repair it and i took the covers off and had a multimeter reading on the potentiometer. The marking on the potentiometer are "A50k" and i had a reading of 30 ohms when it was at turned all the way up, and 0 ohms in every other position. Am i safe to assume the issue is the potentiometer and a replacement will fix it?
Thanks in advance!

[allanturton]

My potentiometer has a wire coming out from the opposite end of the prongs; do you know what it is for? The component was pulled from the LR balance on a 1980s stereo; Thank you!

[BlackRaven-YT]

Im doing a repair on a antique lamp my potentiometer uses a spring stopper wall I was preparing it the spring popd out how do I put it back in ive ben trying for hours