Do inductors sing in old age? - Page 1
Forum section: electronics / beginners

author: NivagSwerdna
author_rank: Super Contributor
timestamp: May 12, 2019, 02:11:51 pm
content: I built a nixie clock a few years ago and I have noticed it has got quite loud... at first I thought it was the tubes singing and a multiplex effect but I am now pretty sure it is the inductor in the HV power supply.The inductor is a 220uH CoilCraft job.The clock has been on continously for around 2 years... do inductors wear out? Sing in old age?

author: BravoV
author_rank: Super Contributor
timestamp: May 12, 2019, 02:41:20 pm
content: Thermal cycle eventually will make something loose.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 12, 2019, 03:57:27 pm
content: More often it's always singing, and either you never noticed it (too high frequency? Environment changed to make it more audible?), or the singing frequency changed.Adhesives can conceivably fatigue loose but I wouldn't think this very common, unless it's been exposed to temperatures so hot that magic smoke could be smelled.The frequency can change due to marginal compensation and aging of electrolytics or the like. Electrolytic capacitors are the component most prone to aging.Shall I guess it's the usual shitty Nixie supply circuit, no protection or nothing?Tim

author: Berni
author_rank: Super Contributor
timestamp: May 12, 2019, 07:04:51 pm
content: It could certainly be something getting loose due to thermal cycling.Often a reason for switching supplies starting to make noises is the electrolytic caps gradually degrading in performance. This makes for more ripple on the rails and this ripple can cause ceramic capacitors to make audible noise trough the piezoelectric effect.The trick i use for locating the noisy component is to press tweezers on components one by one until i find one where the sound changes when poked. This mostly works by the tweezers picking up the vibrations and vibrating along it to make the sound louder.

author: Benta
author_rank: Super Contributor
timestamp: May 12, 2019, 07:39:05 pm
content: Be happy that it sings! Most inductors just hum, and it's a major task to teach them the lyrics!Sorry, couldn't resist...

author: MarkF
author_rank: Super Contributor
timestamp: May 12, 2019, 07:44:28 pm
content: Quote from: Benta on May 12, 2019, 07:39:05 pmIt needs some backup singers...Check the Fluke 98 song in this other threadhttps://www.eevblog.com/forum/beginners/custom-firmware-for-old-oscilloscope-(ideas)/msg2405760/#msg2405760

author: Brumby
author_rank: Unknown
timestamp: May 13, 2019, 12:32:52 am
content: Quote from: Benta on May 12, 2019, 07:39:05 pmIcouldsay "try harder" .... but it made me smile.

author: Berni
author_rank: Super Contributor
timestamp: May 13, 2019, 04:15:32 am
content: Quote from: Brumby on May 13, 2019, 12:32:52 amWell the music industry is prettysaturatedthese days anyway.

author: innkeeper
author_rank: Unknown
timestamp: May 13, 2019, 04:39:23 am
content: it's trying to get inducted into the rock and roll hall of fame.and to think it knows only 1 chord.

author: Brumby
author_rank: Unknown
timestamp: May 13, 2019, 05:54:25 am
content: Please tell me that's all...... Please.* Thinks: You hypocrite ... you're still smiling! *

author: CJay
author_rank: Super Contributor
timestamp: May 13, 2019, 08:52:24 am
content: Yes, they can do, I've also heard inductors/transformers 'singing' because of other components going faulty (electrolytics usually), changing those bits silenced the inductors

author: NivagSwerdna
author_rank: Super Contributor
timestamp: May 13, 2019, 09:28:01 am
content: I attached the clock to a lab power supply and gave it 12v and then adjusted the voltage down. Interestingly at about 11v it is considerably quieter and then gets louder again towards 9v. I also notice that it is quieter when not under load.I really don't remember it being this noisy and putting my ear close I can perceive what might be described as fizzing or at a stretch crackling.Perhaps I should preemptively replace the input electrolytic? (Which is a PITA since it is SMD flavour)Just checked my schematic and I'm pretty sure I ended up with..."EEEFTH101XAP - SMD Aluminium Electrolytic Capacitor, Radial Can - SMD, 100 µF, 50 V, 0.34 ohm, FT Series" on the input side. That looks like a good choice... not sure I have any spares.

author: soldar
author_rank: Super Contributor
timestamp: May 13, 2019, 11:07:03 am
content: I had an old hard disk that would sing the Travi-ATA.The newer ones do the Travi-SATA

author: CJay
author_rank: Super Contributor
timestamp: May 13, 2019, 11:19:11 am
content: Could be input or output, could be both, could be neither and it could be a loose winding on the inductor as well.

author: Mechatrommer
author_rank: Super Contributor
timestamp: May 13, 2019, 11:28:58 am
content: yes they do sing old or new... if you have more time to kill you can build something useless and have a life by getting 50K likes, and possibly participate in america got talent or hope george lucas will hire you and then have some stories to tell your grand children.

author: GreyWoolfe
author_rank: Unknown
timestamp: May 13, 2019, 11:38:33 am
content: Quote from: soldar on May 13, 2019, 11:07:03 amHere we are, the beginning of the week, Punday.