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[wierd]

I have an actual WTF.

I was adding a bell to our doorbell system. There were 2 already, I was adding a third. Of the original 2, 1 is an electromagnetic bell, the other plays a melody.

Now, I was doing this with the bell system active, as the voltage in it is miniscule and can't pierce skin. What surprised me though was, that at several poits, the one that plays melody went off. It coincided with when the wires were shorted (such as when I was shortening them, and my knife was touching both of them).

But since my knife is not a power source, I do not think this should have done anything. Based on my knowledge of how electromagnetic bells work, even with the wires shorted, there should have been no closed circuit without someone pressing the bell button on the door. The electromagnetic bell was not triggered randomly anyway and I did check that it still worked when the button was actually pressed. I checked the door as well and there was nobody there.

There is no conceivable way that the solenoid array used to strike the bells, is powered by the signal line used to initiate the process.

More than likely, you have a biased 1 bit transistor latch, wired to the button, which then drives an output value, that triggers an externally powered solenoid and capacitor array.  (and since it plays music, likely behind at the very least, a simple counter and TTL array, so that the plungers fire in the correct sequence.)

simply shorting the bit on the externally powered 1 bit memory cell, would be sufficient to drive voltage high to voltage low, and thus toggle the circuit's state.



Note that signal in, is just a status of "on" and "off".  Direct short is "off".  The rest of the circuit is externally powered. (see the other VCC lines.)

[Mathel]

I actually took the old bell apart at some point, to remove rust, and it is powered by the signal.
This is the layout of the old bell.


The signal is also what powers it. I do not know which side is positive and which negative, I just made sure I plugged it in back the way it was before. It would also work on AC though, if it is plugged to the grid and stepped down somehow.

When you press the button, the coil attracts the magnet, which pulls on the hammer and bends it away from the bell, breaking the circuit. This stops the coil from working, the hammer quickly straightens, striking the bell and competing the circuit. If the button at the door is still held, the cycle repeats.

I did not get a look at the circuit board in the one that plays a tune, but I do know it has 2 AA batteries.

Edit: All the bells are plugged paralel to each other.

[bloop_bleep]

Yeah old bells that ring a bell a bunch of times tend to have electromechanical components. The signal from the doorbell starts a cycle where an electromagnet switches on and off which cycles a solenoid hitting the bell a bunch of times.

[Mathel]

While taking a shower, I realised several things.

First, weird may have been talking about the the electronic tune “bell“. It has a speaker, not real bells though, which confused me.

Second, the signal has to be a stepped down grid power. Not sure if it is rectified though.
If it is, then weird's explanation still holds. Capacitor slowly charges, discharges on shorting, causing the device to activate.

[nenjin]

Libido, please stop the train. I would like to disembark.

[pisskop]

Chooo Choo, hown would you like to ruin a relationship with sexual in-your-end-o?

[nenjin]

So many great options to choose from!

[Grim Portent]

So apparently in 1579 the town of Appenzell, Switzerland, nearly entered an armed conflict with their neighbouring rival* St Gallen after a printer in St Gallen printed a number of calenders for Appenzell with an incorrect coat of arms.

The specific error was that the bear on the Appenzell coat of arms was not pizzled. Pizzled being the heraldic way of saying 'with a penis as part of the design.'**

So this town almost decided to attack their neighbour, because some dude in that city forgot to put a dick on the bear in their calender.



*Religious and political differences as I understand it, though economically tied.

**I couldn't find anything about why the penis is included sometimes, but apparently people thought sticking red rockets on bears and lions was a good part of proper crest design.

[nenjin]

It doesn't take much to imagine. The pizzle is symbolic of the animal's manhood, and since it's the crest of the town, symbolic of all their manhood too.

I can see, in those times, that being the basis for someone's war.

[MrRoboto75]

for rizzle, it needs the pizzle to be the right schizzle

or else my face shall drizzle.

-----

Today involved me subbing a video about the four US planes involved in a 1924 first voyage around the world.  I have to google the names of those involved, y'know to spell the names right.

The first plane, the Seattle, crashed somewhere in Alaska in basically the first leg of the trip.  In googling the co-pilots name (Alva Harvey), I learned not only did he somehow survive the crash after some 10 days in Alaskan wherever, but lived on test pilot and develop WWII planes and beyond, including the Flying Fortress.  He passed of basically old age maybe 20 years ago.

Guy was apparently a badass, and wasn't even entirely credited as a world flyer.

[Frumple]

pizzle drizzle is like the last thing you want on your face, true

on the other hand i'm pretty sure the pizzle being missing is how you avoid that, not by having it around, so

[King Zultan]

but who was phone?

That's the age old question isn't it, we may never know the answer but we all stop periodically and ask ourselves that all important question, who was phone.

[Mathel]

but who was phone?

Her mom, who was stalking the guy.

[Frumple]

Walk by tv on infomercials. Dude shilling some kind of beauty product.

Says lots of fancy, roundabout words, then says more clearly: "It takes off the top layer of your skin."

 And I'm just, like. What?

[methylatedspirit]

I just realized that Paulstretch changes the length of audio at a Stretch Factor of 1 (which is supposed to be "don't change the length"). I know this, because I was fucking around in FFmpeg trying to databend raw YUV images, and it kept complaining that the buffer length isn't right, and it's corrupt and stuff. How you can tell that an uncompressed, un-checksummed file is corrupt, I don't know.