Hacking A Doorbell

[swiftguy]

Hi guys,

I currently have an external pir when it detects movement it turns on a plug socket (inside the house) via RF.  It also has a chime bell, this keeps ringing so long as their is movement outside and gets annoying after awhile. 

I'm looking to have just a ding-dong sound that plays once only the first time movement is detected - something I can plug in, so when the socket turns on, it sounds the bell once.  The socket then automatically turns itself off after a pre-set time. 

I've been struggling to find something I can just plug in and will play a short sound. Do you guys have any ideas?

I've thought about hacking a doorbell to achieve this.  Just wanted to make sure this was ok.

So plan is using a traditional wired doorbell that makes a 'ding-dong' sound.  If its a 12v doorbell, I need a 12v adaptor and connect the wires that would go to the bell from the transformer and push-button to the adaptor via a dc plug.  So when the plug socket turns on, power is delivered to the doorbell energising the solenoid, it will make a ding sound and the solenoid remains powered till the socket turns off and then make the dong sound.  I take it there is no problem leaving the doorbell powered for about 1min? as normally the push button is released fairly quickly.

My other thought is of hacking a wireless doorbell. Here, I would need to hack the wireless push button (as not sure if I can hack anything on the doorbell receiver itself.)  The wireless push button takes a CR2032 battery which is 3v.  So if I have a 3v adaptor and wire this to the push button terminals, so when the plug socket turns on, it would simulate a push button press and send the wireless signal to the bell receiver.

What are your thoughts on this?

thx.

 

[steptoe]

ok, so if I understand this,

you want to 'hack' a doorbell,

obviously means a lot different to when I was hacking stuff, :slap

even now, I wouldnt exactly call it hacking when I show the neighbour how I can break their wi-fi password,

its hardly hacking on a doorbell,

TBH, its sounds as if your idea of your ability far outstretches your actual ability.

 

[SPECIAL LOCATION]

Sounds like you are trying to use a pir light sensor as a primitive type of intruder alert system..

why not just use a proper intruder alarm sensor and/or panel..

commonly used in shops, or unmanned service counters to alert to the presence of a customer entering...

e.g

http://www.ultrasecuredirect.com/acatalog/100m_Working_Range.html

alternatively use a beam that is broken rather then a wide angle sensor..

OR..

drop the operate time down on the PIR to its minimum...  seconds rather than minutes...

It does sound as though you could be doing a lot of waster effort to achieve very little!

 

[swiftguy]

Sounds like you are trying to use a pir light sensor as a primitive type of intruder alert system..

why not just use a proper intruder alarm sensor and/or panel..

commonly used in shops, or unmanned service counters to alert to the presence of a customer entering...

e.g

had to delete this as I'm not allowed to post links

alternatively use a beam that is broken rather then a wide angle sensor..

OR..

drop the operate time down on the PIR to its minimum...  seconds rather than minutes...

It does sound as though you could be doing a lot of waster effort to achieve very little!

Thank you for at least posting a reply in a way that is trying to help.

Perhaps if I tell you what I'm using this for might help clarify.  When someone steps foot onto the family home, I would like a tv/monitor to come on automatically, which would would be connected to the cctv camera.  Thus I and family members would be able to see straight away who was there.  The problem with traditional intruder alarms is that they don't cater for this or none that I have come across.  

I have bought a product which consists of an external wireless rf pir and a rf plug with built in chime and timer.  I simply connect my monitor to the plug and bingo. Nice and simple.  It comes on automatically when it detects motion outside and then goes off by itself.  No user intervention required and works like a charm.

I've not seen intruder alarms that provide this sort of functionality.  Which is key in my opinion, as you should have the ability to know how is on your property.

I have looked at beams, but the outputs are designed to feed into an alarm system, and with my limited ability as highlighted by steptoe, I probably stand no chance of getting the beam to turn on mains plug to power the lcd monitor.

Back to my post, the built-in chime of the rf plug keeps ringing so long as their is motion, which like I said gets annoying, as all that is required is an initial sound to alert family members to look at the screen.

(steptoe - take note, you maybe Einstein of all things electric -but we all have to start somewhere - trying to drop a boulder from a great on someone and trying to quash what little confidence they have in their own abilities is not very nice.)

 

[wozz]

I've done something similar with a wise box, wireless pir and a multifunction din rail timer using the hold on function for a few seconds. 

 

[Andy™]

and here was me expecting methods on being able to sound your neighbours doorbell from the comfort of your own home, just to annoy them, or block the signal from their push button so they dont answer...

 

[SLIPSHOD & SLAPDASH]

All I can say is try it & see. The worst will be the coil on the ding-dong will fail. You will find most bells are 3-8 volt so buy a 'proper' door bell transformer, some have 3 output voltages & I would  use the lowest one first.

 

[Barx]

I once did a door bell hack and it went rather well. door bell was an existing wired system. You pressed the button and it gave a constant br-r-r-r-r-r-r-r-rr-r-r until you let go. The guy, this was a car repair garage, wanted it to also operate for a few seconds if the reception external door was opened. This was so he would know if someone entered the reception whilst he was working on cars in the garage. I used a PICMicro controller. I wrote the code for it. It was powered from the existing doorbell transformer and so i needed to built a bridge rectifier and add voltage regulation. the output trigger was a transistor switch, switching a relay that in turn closed the circuit for doorbell to activate. Timing done in the PICMicro. and the input was a security alarm door contact. Only had 1 issue and that was induced emf from a  nearby heating system. it would trigger the doorbell when heating switched, lol. Added a backfeed filter diode and all was well. Still working to this day (about 5 years on).

I know this doesn't really help you but I thought I would share my doorbell hack and now you know your not alone. There is a group of us doorbell hackers.

 

[Andy™]

since were telling doorbell stories ill add mine...

similar to Barx, something loud needed in workshop when door opened. used a door contact to trigger a timer lasting 2 seconds. connected timer to an alarm sounder

which thinking about it, may be all you need. the timer stopped after a few seconds regardless of input still being there or not iirc

ill havea look later and see if i can find the timer i used

 

[swiftguy]

Wozz - thx, for the pointer regarding multi-function din rail timer, something for me to read up on and see if I can use it.

Slipshod - advice noted, I guess the real purpose of the post was to see if there was a better 'proper' way of doing this, as I'm new to this field so don't know much about what devices are available to achieve this sort of thing.

Barx - pretty cool, certainly give me food for thought and ideas.  I'm looking at getting an arduino later to add some logic and home automation to the overall project. 

Andy - would be very interested to know what timer device you used, as it sounds ideal for my situation.

thx

 

[SLIPSHOD & SLAPDASH]

I keep one of these in the van, very handy for door entry, gates etc  http://www.maplin.co.uk/mk111-adjustable-timer-with-relay-output-25224

 

[Andy™]

I keep one of these in the van, very handy for door entry, gates etc  http://www.maplin.co.uk/mk111-adjustable-timer-with-relay-output-25224

i think that may be the same timer i used

 

[swiftguy]

I keep one of these in the van, very handy for door entry, gates etc  

Thanks, will try it out.

 

[SLIPSHOD & SLAPDASH]

I used to use 'Hoyles handy little relay' but they dropped the timer function from it.