A Doorbell Loud Enough To Wake The Dead


[Ed Nauman] runs a machine shop, which we imagine can be quite loud at times. Sick of never hearing the doorbell when he was busy working on things, he decided that the solution to his problem was a new doorbell…an incredibly loud doorbell.

His Really Loud Doorbell (RLD for short) is actually a pretty simple device. We imagine he could have wired up an old alarm bell instead, but where’s the fun in that? The doorbell was built using a PIC16F876 uC, which is used to control the air flow through a pneumatic valve. When someone rings his doorbell, the pneumatic actuator pulses up and down, rapidly striking a piece of 1/4” thick steel pipe. As you can see in the video below, it is quite loud and likely to cut through any shop noise without much trouble.

We have seen some extremely loud doorbells before, but we figured that at least a handful of you work in similar environments – have you implemented any inventive ‘notification’ systems in your workspace? Let us know in the comments.

[via Adafruit Blog]

[brightcove vid=1020983766001&exp3=991410168001&surl=http://c.brightcove.com/services&pubid=1568176135&pk=AQ~~,AAAAAETaO0s~,cVbOypIs9tHUVW57d5nJxZGxNa9O_LLK&w=470&h=412]

43 thoughts on “A Doorbell Loud Enough To Wake The Dead

  1. Most deaf people just use a flashing light. I don’t see why making a louder doorbell is the optimum solution. What happens when machines and hearing protection are off? Then you get notification of a visitor and hearing damage. Just get a strobe light and fix the issue – no custom work required.

  2. +1 to Hackerspacer’s comment. I have a friend that runs a (fairly noisy) plastics shop and he has his phone hooked up to a pair of strobe flashers at either end of the shop. I can’t imagine it’d be too much work to set up something similar for a doorbell.

  3. Hard to judge from a video. My guess that the old outdoor telephone ringers would do a better job. The only time this thing actually rings is when the striker stop beating the hell out of of the pipe. Perhaps changing the program to add a delay between the strikes could improve it. The triangle bells constructed from a rod work well, because a delay between strikes is built in, doesn’t manner how fast a maniac ringer spins the striker there’s always going to be that delay.IMO of course.

  4. I can’t hear the doorbell where i am in the house and I didn’t want a light adding to more blinky flashy things in the room or just a bell. So I modified a air-wick iMotion air freshener to dispense only when the bell goes. The freshener disperses really quickly all over the room.

    Now when the doorbell goes, I get a unique air fresher smell dispensed into the room which I know means there’s somebody a ringin’. Also if i’ve got my eyes closed listening to music or am looking in any direction in the room I still know I’ve a caller.

    Why not use all your senses, eh?

  5. @Quincymd: That’s a really cool idea!

    Too bad it wouldn’t work for me. The UPS guy rings the bell and runs out of here like the White Rabbit from Wonderland, and I barely manage to catch him and get my packages before he drives off. Any extra delay for the *smell* of the door, and he’d be gone.

    Whereas people I don’t want to talk to are generally more persistent, and I don’t want to be gassed out of bed by members of every Saturday morning.

  6. UPS here often just opens the door and tosses the package inside, without even bothering to ring the bell. Heck, lately, the only people who actually ring the doorbell are thieves looking for a handout while casing the joint.

    I’m all for a flashing light, though. Especially one rigged to a PIR or similar sensor so they don’t even have to ring the doorbell – a person’s mere presence on the doorstep is announced. Heck, I picked up a cheap doppler radar module on eBay a while back; if I ever figure out how to make sense of its output (datasheet is very, very lacking) that could be a useful application for it.

  7. @Hackerspacer I wondered this aswell, and after some googling it seems to be an automatic alarm that sounds if the Bridge of the ship goes unattended for a period of time likely indicating an incident of some sort. Although I’m probably wrong so feel free to point out of im wrong haha.

  8. @Hackerspacer & Skeptic & Limey:

    The deadman alarm, is IN-FACT, an alarm to notify of unattended controls, as follows:

    “Our navigator safety system or “dead man alarm” is designed to monitor bridge activity and alert the master or other qualified navigators if the bridge becomes unattended. The system first alerts the officer of the watch through local alarm indication at the bridge unit and, if he is not responding, then alerts the master or other qualified officer”


  9. You guys must really like headaches (and going deaf).

    Sane persons solution:
    Strobe light
    simple circuit to get the relay to stay closed for say 20 seconds with a push of the doorbell.

    If your ears are still ringing after your guest has left then your probably going about it all wrong. Your sense of hearing is already overloaded to an extreme use a different sense.

  10. “Implemented any inventive ‘notification’ systems in your workspace?”

    I’m working on a Blueooth-based doorbell.

    I was tired of co-workers trying to get my attention when I had headphones on so I created the BDB-5000 Bluetooth Doorbell to connect to my Droid and ring through my headphones when someone presses the button. I have some demo videos on my blog (click my name).

  11. A bit OT since it’s not about the loudness, but I did see an excellent doorbell hack at a museum in Fort Langley, British Columbia. A string tied to the door went through a series of pulleys, ending up pumping a bellows placed next to one of those wooden “train whistle” toys. The effect was really neat, not to mention entirely appropriate. (Also, it made me think of The Incredible Machine. :D )

  12. @hackerspace A similar device to a deadman alarm is what firemen have on their waist. It’s a little accelerometer/gyro. If they dont move for 10 seconds it starts beeping and flashing.

  13. This reminds me of a story from a place in the Netherlands.
    there was a man struggling to hear his alarm clock. So what he thought I make a 250watt alarm and yes it worked fine.
    until he once went on vacation and forgotten to turn off his alarm clock. When he was gone so he went off at 7am in the morning and took away half awake which is not very liked
    The police had come to the house to go to the mega-alarm zetten.de owner did get a pay for noise nuisance

  14. If he wanted to do a really loud alarm that’s fine but he should have at least added the ability to measure the noise in the shop and then adjust the volume of the alarm based on that. This would be very annoying when all’s quiet.

  15. You could always use a microphone and one of the PIC’s A->D converters to measure ambient noise before ringing the bell. An extra valve could be used to actuate the cylinder using a restrictor in the line to decrease the force the “bell” is struck with.

  16. You know for everyone complaining about hearing loss and that this is too loud, remember that this is a machine shop. It is clearly already too loud to hear the doorbell and it should be assumed that these guys are wearing earplugs. The bell probably just breaks through the din of the other machines to get his attention.

    That said, you can’t do anything to protect those visiting the shop unless you hand out plugs upon entrance. Perhaps an override switch for quiet times could be installed.

  17. Sorry for the delay in replying to the questions about the deadman alarm.

    Larger ships run UMS – unmanned machinery space. This means that all of the machinery is automatically controlled or remotely controlled from the bridge. Engineers simply perform 0800-1700 day work, maintaining the machinery.

    However, every day there is a duty engineer. Between 0800-0900, 1600-1700 and 2300-2400 you do a walkaround in the engineroom, going through a long list of items, monitoring temperatures, flows, levels, and just keeping an eye on things.

    For the 0800 and 1600 check, the engine room is in “manned” mode – there are other people there so you just do the walkaround and if anything happens to you, then someone will see you or notice you are missing.

    The 2300 walkaround is done by yourself. If you were to be injured or trapped, you would be waiting until 0800 for someone to find you.

    So you activate the deadman alarm. This means that you need to press a button every 5 or so minutes to reset a timer. The buttons are located at doorways and other points around the engine room. If you don’t press it in time, the klaxon sounds an the traffic light flashes. You have about 30s to get to a button to reset the timer.

    If you don’t, an alarm will sound on the permanently manned bridge. Generally the bridge then calls the engine room. If they receive no answer, the general alarm is sounded across the ship.

    There is a similar alarm on the bridge. If none of the controls or computer systems receive manual input for more than 15 minutes, the general alarm is sounded. There is also a button that can be pressed when a beeper signifies the time is up.

    The telegraph alarm is barely used as the engines are controlled remotely from the bridge. There are drills to ensure engineers can control the main engine from the sticks in case of control system failure:

    The machinery alarm is for any of the machinery alarms – low oil pressures, high temperatures, low tank level, there are literally thousands of sensors.

    The CO2 alarm is sounded when any of the control panels are opened for the CO2 flooding system. This is used to fill the engine room with CO2 in the event of a fire. You hope never to see this one, unless it is being tested.

  18. I have family members who work in less noisy places(mostly freight handling) that yell all the time cause their hearing is shot..people with no laborers in their family have it all figured out though..

    I had to cut my parents lawn once, let me inform you of the realities of the working class xD

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.