The EEVblog Lab VIBRATES! - Page 1
Forum section: electronics / general

author: Mr.B
author_rank: Unknown
timestamp: March 04, 2019, 01:56:45 am
content: Is it time to invest in a vibration logger Dave?It would be interesting to know what frequency it was. That would help you track down the source.Unfortunately, good ones with a high sample rate don’t come cheap.

author: Mr. Scram
author_rank: Super Contributor
timestamp: March 04, 2019, 02:05:37 am
content: Sounds like resonance. I've got items in cupboards in two unrelated locations shudder along with some distant and generally unheard vibration. One was a digger on a adjacent building site, the other some unknown device with a more consistent pattern.

author: coppercone2
author_rank: Super Contributor
timestamp: March 04, 2019, 02:15:28 am
content: you sure its not a shitty HVAC

author: MarkL
author_rank: Unknown
timestamp: March 04, 2019, 02:44:26 am
content: I'll bet it's the air handler of your downstairs neighbor. They're often attached to the ceiling.

author: bsfeechannel
author_rank: Super Contributor
timestamp: March 04, 2019, 04:31:26 am
content: This is the Australia moving northeast. In 50 million years, Australia will be touching the shores of China. Freight will be a bargain.

author: tautech
author_rank: Super Contributor
timestamp: March 04, 2019, 04:44:15 am
content: Camera is likely in sequence with any vibes so won't show them well.Use a glass or bowel of water.

author: jesuscf
author_rank: Frequent Contributor
timestamp: March 04, 2019, 06:09:18 am
content: It may be infrasound. Had some experience with infrasound a decade ago or so. Extremely annoying for people than can 'feel' it. We detected the source, a large ventilation fan, using geophones. I remember watching a video of a vertical bar that oscillated because its natural frequency matched the frequency of the infrasound; of course, I can not find that video now...With a pan and some salt, maybe some nice Chladni figures can be obtained:

author: 3roomlab
author_rank: Frequent Contributor
timestamp: March 04, 2019, 08:10:56 am
content: shoot the video again? this time put a small mirror there and measure a reflected laser beam or light on the wall?edit : it could be worth it to record the amount of "movement"and if it gets worse, you might need some evidence to complain to the landlord?

author: NivagSwerdna
author_rank: Super Contributor
timestamp: March 04, 2019, 09:12:58 am
content: Bring on the EEVBlog sesimograph. I have often mused about building one of those and the rabbit hole goes deep in that area, would make an interesting series.

author: Rerouter
author_rank: Super Contributor
timestamp: March 04, 2019, 09:23:51 am
content: Just need to record the frequency, In my head it would be the HVAC compressor pump on the roof, (Just break open a piezo buzzer and stick it to the box top),

author: Kleinstein
author_rank: Super Contributor
timestamp: March 04, 2019, 09:48:54 am
content: Quote from: Rerouter on March 04, 2019, 09:23:51 amAn alternative make shift vibration sensor can be made from a speaker and some weight on it. This should be sensitive enough to see an a scope.

author: HalFET
author_rank: Frequent Contributor
timestamp: March 04, 2019, 10:23:27 am
content: Maybe you can extract power to run your lab from this vibration using ...graphene?But yeah, a magnet with a coil works quite well to measure these things.

author: EEVblog
author_rank: Unknown
timestamp: March 04, 2019, 10:40:21 am
content: Quote from: coppercone2 on March 04, 2019, 02:15:28 amNot mine, it was switched off.

author: EEVblog
author_rank: Unknown
timestamp: March 04, 2019, 10:43:22 am
content: 9:45pm in the lab and it's now gone

author: snoopy
author_rank: Frequent Contributor
timestamp: March 04, 2019, 11:21:22 am
content: Quote from: EEVblog on March 04, 2019, 10:43:22 amYou sure you are not located next to the OPAL tower ?Otherwise check for poltergeistsLOL

author: SeanB
author_rank: Super Contributor
timestamp: March 04, 2019, 03:41:05 pm
content: Quote from: EEVblog on March 04, 2019, 10:43:22 amMain building AC turns off at 9PM I would guess, and this is very likely the cause of it. Big central plant, either refrigerant to water with a set of Sulzer water air heat exchangers on the roof, or a big set of 3 phase scroll compressors in a multi setup driving a massive condenser, with a big fan there with belt drive and a 2 horsepower 3 phase induction motor to move the air through it. Most likely refrigerant water, as that allows individual units to have local compressors, though with the multi unit on a smaller set it is cheaper, though it costs a lot more power wise to run than letting water evaporate and draw some of your heat away.Time to heat to the roof with a camera and see what makes the most vibration.

author: MT
author_rank: Super Contributor
timestamp: March 04, 2019, 03:46:53 pm
content: Dave lab is infested by mating song of the Indies short-tailed cuban crickets!https://phys.org/news/2019-01-cuban-crickets-weapon-heard-ill.html

author: coppercone2
author_rank: Super Contributor
timestamp: March 04, 2019, 03:48:30 pm
content: doesnt that sounds like the most bootleg explanation?I mean I am not contesting it because I did not do a investigation, but its like one of those bad C-grade horror movies where some old hillibilly says man sized footsteps 'must be the cat'.

author: Andrew McNamara
author_rank: Regular Contributor
timestamp: March 05, 2019, 12:06:11 am
content: Quote from: SeanB on March 04, 2019, 03:41:05 pmThis reminds me... owner of a building we were in decided to replace their two large turbine A/C compressors with sixteen reciprocating piston compressors, which were allegedly more efficient (but only because it yielded 16 levels of control). The new compressors were so noisy, it rendered the top two floors of the 20-storey building unlettable - it sounded like a demented band of madmen with sledgehammers pounding on the roof. The copper buss bars feeding the A/C also ran so hot after the "upgrade" they felt like bar radiators, so I was sceptical of the claimed efficiency gains.

author: coppercone2
author_rank: Super Contributor
timestamp: March 05, 2019, 12:23:58 am
content: sounds like a husky product lol

author: s8548a
author_rank: Regular Contributor
timestamp: March 05, 2019, 12:30:23 pm
content: from the title, I thought you have got a new toy, vibration tester.

author: SaabFAN
author_rank: Frequent Contributor
timestamp: March 05, 2019, 04:30:54 pm
content: Quote from: Mr.B on March 04, 2019, 01:56:45 amHe repaired a Stanford Research Dynamic Signal Analyzer a few hundred videos ago. That would be the perfect tool to measure this and would also show how to use these thingsWould definitely make for an interesting video.This vibration-thing is also a good excuse for bad soldering LOL

author: coppercone2
author_rank: Super Contributor
timestamp: March 05, 2019, 05:04:49 pm
content: I got a nasty 280 hz or something frequency from a drain pipe in an apartment i was visiting. Enough for phone to pick up 20db above average

author: Brumby
author_rank: Unknown
timestamp: March 06, 2019, 01:41:41 am
content: So - back in the lab today... Does the VIBE live again?

author: Halcyon
author_rank: Unknown
timestamp: March 06, 2019, 03:12:38 am
content: Same thing happens in our building at work. Shelves are constantly vibrating.

author: larrybl
author_rank: Regular Contributor
timestamp: March 06, 2019, 02:13:23 pm
content: That's not a big issue, I live 8 km from this. Knick knacks will walk off the shelves.

author: Andrew McNamara
author_rank: Regular Contributor
timestamp: March 07, 2019, 01:02:20 am
content: My bet would be on A/C plant, but another possibility is tunnelling - Dave is close to the Northwest Metro. I think their tunnelling should be done by now, but they could be doing some other process that produces vibration. A friend of mine lives above NorthConnex, and their tunnelling has shaken his house to bits - not only have walls cracked, but anything placed on a shelf ends up on the floor before long.

author: TheNewLab
author_rank: Frequent Contributor
timestamp: April 23, 2019, 06:07:03 am
content: Quote from: bsfeechannel on March 04, 2019, 04:31:26 amLOL!Just like the California coast dropping into the sea!

author: TheNewLab
author_rank: Frequent Contributor
timestamp: April 23, 2019, 06:11:17 am
content: Quote from: EEVblog on March 04, 2019, 10:43:22 amI was leasing a commercial studio in a big building. I had the problem when working late and disappear during the day. Turned out to be a band practice studio at other end. could not hear the music but the vibration made it through the floors.So could it be a neighbor? quit because they went home?

author: EEVblog
author_rank: Unknown
timestamp: April 23, 2019, 07:45:13 am
content: Quote from: Andrew McNamara on March 07, 2019, 01:02:20 amNope, long since finished all that work.