I think I’ve asked this before, but I couldn’t find it.
When I was in college, I worked in the theater. And, we had a phone ringer installed on the set. I don’t know how it was done, since it was there when I arrived, but I need to reproduce it.
You see, there was a phone jack on the set and a button in the tech booth. When a phone was plugged into the jack and a techie pushed the button, the phone rang. It rang however it was designed to, and the ring pulsed, just like it would if a call was coming in.
(Is that clear? It went “Ring… Ring… Ring…” just like a real phone call. And when you answered it, it stopped!)
All the techie had to do was hold the button down. It all happened automatically.
I just know that this can be done with supplies from Radio Shack. I just don’t know how. Can anyone help me?
How much do you want to spend? I found one [that costs $140, plus $18 for the optional AC adapter. I’m assuming it otherwise uses batteries.
If you want to get fancy, and ring phones and doorbells by MIDI control, here’s [url=http://www.masque-sound.com/products/prodpages/urg.html]one](http://www.musson.com/catalog/Musson2003Sound.pdftheatrical ring generator[/url) that sadly, has no price info.
If you want to go cheap and live dangerously, try feeding a phone plain ol’ 120 volt AC wall power. It’s not terribly far away from what a phone really rings on - 90 volt AC at 20 Hz.
How much do you want to spend? I found one theatrical ring generator that costs $140, plus $18 for the optional AC adapter. I’m assuming it otherwise uses batteries.
If you want to get fancy, and ring phones and doorbells by MIDI control, here’s one that sadly, has no price info.
If you want to go cheap and live dangerously, try feeding a phone plain ol’ 120 volt AC wall power. It’s not terribly far away from what a phone really rings on - 90 volt AC at 20 Hz.
I’m not that clued up on these things, but I guess you need to make a flip-flop circuit with a potentiometer to vary the length of time before each ‘flip.’
As a kid I had a little book showing how to make one from (as far as I remember) a transistor, an electrolytic capacitor a resistor or two and a potentiometer, which I no longer have. It’s extremely simple. I did a very quick search for a circuit diagram, but all the results were for ICs or computer programming. Maybe it’s now possible to buy the thing ready made in chip form at Radio Shack?
Then you need to hook the flip-flop circuit up to a relay. Put all this in a plastic box with a phone socket on the side and a pushbutton that switches on the flip-flop circuit when depressed.
Then use the relay to switch the right amount of current to the relevant poles of the phone socket. (I’m not sure I recommend using mains electricity for this, as per gotpasswards’ suggestion!) Plug a phone into the socket and experiment with the pot on the flip-flop circuit to get the length of the ring the same as with a normal phone.
Aha! Here’s a circuit diagram for a light flashing circuit. It uses a chip rather than transistors. Simply replace the light bulb with a relay to switch the current to the phone.
One question. Is the space between the rings the same length as the ring itself? If not, I’m not sure how you’d adjust the length of the interval, but it should be quite easy for someone who actually knows what they’re talking about…
Another angle: play a WAV file (or tape) of the recorded sound. My ICQ has the sound of an electronic ringer ringing once and it is easy to make a file with 2 - 3 rings.
trabi – There’s an easy way around the “call at an inappropriate moment” which is to either make the stage extension an unlisted, private number known only to the stage or theater manager or keep another extension off the hook during performances except for the moment directly before the on-stage ring was needed.
To avoid the busy cellphone issue, have two phones on hand. It always serves in the theater to have some kind of backup, after all.
TeaElle, of course you should always take precautions, but you should never underestimate the power of Sod’s law
On a less flippant note, the question in the OP was quite specifically about how to construct - using parts available from Radio Shack - a phone ringing device similar to the one he saw used in a theatre at school.
(Whether or not he actually needs it for use in a theatre has not yet been revealed to us…)
The other problem with the cellphone method is that the amount of time it takes to connect the call is unpredictable. In a play, the timing of the ring could be absolutely crucial to the timing of a joke, for example. Or it could be needed to cut someone off in mid-sentence. Using a cellphone would be too hit and miss.
The sampling method gets around that problem, but lacks realism. It is obvious to the audience that the noise is being piped over the PA system, and not being made by the phone itself.
Who said the ringing phone audio clip had to be played through the house PA? Run it to something like a guitar practice amp or some similarly compact amp and speaker hidden onstage near the phone.
And, as trabi suggests, making sets and props “practical” is often impractical. :eek:
Here, practical means “actually functional in the normal way” as opposed to stagecraft.
It does? You can buy at Radio Shack a small circuit which will record in memory any sound and you can replay it on demand. The sound can come from the phone itself.
While real bells used AC the electronic ringers use DC. You can easily duplicate the ringer circuit and power it with a battery or just use one from a phone.
Sure, you can butcher a phone and put a little speaker into it (or just put the speaker next to it). And every time you’ll have to set this up, get the volume levels right, conceal the speaker, make sure you’ve recorded the authentic ringtone for the type of phone etc…
The phone ringer strikes me as a neat solution because you only have to make it once, and it allows you to use any phone you like - from any period, to suit any set. Just plug it in and you can make it ring when you like - with its own ringer.
In my personal opinon, it seems infinitely better than wiring up a phone to sound like a phone. (And if you decide you do need to amplify the ringing or somehow alter its sound, you can always mike the actual phone up).
Maybe we should start up a new thread to discuss the relative merits of all these solutions. I’m assuming that the OP has already considered these other methods, but for reasons he has not yet shared with us has decided to go with the phone ringer.
In the meantime, doesn’t anyone else have any answers to the actual question, which was not "how do I make a telephone-like sound in the theatre,’ but 'how do I make a telephone ringer of the type that I saw at college?
