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Build Your Own Rotary-Dial Cell Phone
hwestiii writes "Yet another indicator of how unrepresentative of the main Slashdot crowd I am (meaning 'old') is that, like vinyl records, 8-track tapes, and Pintos, I can remember when rotary dial phones were items of everyday use, and not some object of retro-cool pseudo-nostalgia. Imagine my delight, then at finding this project in which an old rotary phone is turned into a cell phone. To give credit where its due, I originally found it linked from Hack A Day. I know nothing about home-built electronics projects, but this is enough to make me want to learn. If this catches on, imagine what they'll have to do to those 'turn off your cell phone' messages that play in movie theatres."
A quick trick of interest, perhaps good if you're ever in a situation where you can't use the dial pad and can't generate DTMF tones, is the super easy method of dialing a phone with nothing but the hangup switch.
On a mechanical phone (eg, any cheapo phone that doesn't need power or beep or anything), pick it up and listen for dialtone. Then just tap the hang-up switch with pauses for each number. For example, if calling 708-482-0623, you tap the switch 7 times, pause, then 10 times, pause, then 8 times, pause, etc. Rinse & repeat.
It's dirt simple, and most of us already know this, but... it's an easy fun thing to know.
I'm 19, and I used a rotary phone for probably ten years growing up. I'm sure a lot of Slashdotters have if they moved into an older home. The only real drawback to the phones is that there is no way to punch in numbers after connecting. When you hear "Press 1 to ...", the phones cannot handle doing that.
I have fond memories of rotary phones, though. The satisfying click click click, the durable construction; they come from a time before phones were $10 pieces of junk. It's the same reason why so many programmers like the IBM Model-M keyboards.
Systemd: the PulseAudio of init systems
How come you say "dial" a number instead of push a number?
Anyone *really* old remember the letter prefix phone numbers? "Just call Zenith 4265. Operators standing by..."Insert witty comment *here*. I'm fresh out of wit...
Hate to admit this but, here in Pittsburgh, which is far from the middle of nowhere, it still costs an extra $1.50 on your phone bill for touch-tone service. So I can't agree that a rotary phone is "some object of retro-cool pseudo-nostalgia," at least not according to the phone company.
Many years ago, probably the late 80's, I was at a restaurant in Vancouver waiting for a friend who appeared to be late. I was directed to the restaurant courtesy phone and was miffed when I discovered that the call from the restaurant to his home was long distance (Vancouver had some weird long distance rules back then, now fixed). Anyway, the courtesy phone had a long distance restrictor device attached so I pulsed dialed manually by clicking the receiver. All my tapping caused some curious looks from people in the restaurant waiting area, but it worked.
I believe digital switches are much less tolerant and "manual" rotary dialing will no longer work now on digital circuits.
Not at home, but I have one in my office at work. I found it in a cabinet and it was like finding gold; I had not seen or used one since I was about 8.
I took it into my office and put it on the secondary line. I also love the sound of its mechanical ringer when calls come in, and the comments I get when people see it there.
They're amazed when I tell them that yes, it works, and yes you can still dial with it on today's phone system.
Unfortunately, when the analog line it's on is replaced by a VG248 "fake analog" line, which is really VoIP with an adapter, the rotary dial pulses will no longer work. {:(
An era of backwards compatibility is slowly ending. Pulse dialing will slowly stop working on analog phone lines over the next few years or so...
-Z
Back in 1985, there used to be a device made by a company called Tellular that replaced the handset on the brick-phones of the day. That had a dial tone and loop current generator, and sensor for off-hook, (and of course dial pulses, which are rapid hookswitch pulses), and DTMF's. The device would also generate a 100V ring pulse for incoming calls. The net effect was you could plug a standard rotary or DTMF house phone into the box and it would fake a network interface, dial the cell phone and hit send automatically.
I co-designed a system called "Limo-Phone" that interfaced between the phone and the Tellular box to time and charge for the call. This would let a Limousine have a standard TrimLine or Princess phone in the back, the fare could place calls while there like a normal phone, and the device would tally up the bill at the end of the ride!
-- You are in a maze of little, twisty passages, all different... --
I remember being a trepedacious teen trying to work up the courage to call a certain girl... and sitting there with my finger against the stop, the last number (a nine) half-dialled, heart pounding.
:D
I haven't thought about that in years. I guess now you could say it was "Obsolete Panic."
I have an old rotary dal that I converted into a controller for my old Atari 800. I managed to find some black plastic RS232 connectors, some RS232 cable, black duct tape, and the rotary handset. After soldering four lines of the RS232 cable onto the handset, I played around with a voltmeter to figure out which connections were being closed and broken as the dial rotated (interesting to note that 0 generates 10 pulses). These were then wired up to generate a TRIG() press whenever the dial rotated. Fortunately, the rotation of the dial was so slow, even a simple Basic program could determine which number the user has selected.
Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
Regarding your #7--Does this mean if you just tap your receiver hook in an SOS pattern, you might get a visit from your phone company?
I find this to be an interesting comment, because non-rotary phones are *NOT* digital. They (well, in North America) are DTMF, meaning they work with two tones played at once to signal the button press. This is all calculated by having one frequency for each row, and another for each column. When you press a button, the row and column tones are played, making the indicated dual tone. As such, you cannot dial a DTMF phone by whistling, unless you are capable of whistling two notes at the same time.
One other interesting bit of trivia is that DTMF phones can have a fourth column of buttons A, B, C, and D. However, these typically would only be found on test sets and AUTOVON (US Military) phone systems.
The line to our house simply couldn't do touch tone. I don't know why. (I was just a kid!) But we had to have our line 'upgraded' to support it.
I think this was relatively common. Not sure what the technical reason for it was; I should ask my dad, he was a phone company engineer back when there was only one phone company. (Actually there was never really only one.. but you know what I mean)
Remember the phones that had buttons, but still clicked like a rotary? Those were for folks who wanted buttons but who didn't or couldn't upgrade their lines.
I also recall standalone touch-tone generators. Just a touchpad on remote-control-sized box with a speaker that you could hold up the the microphone of a rotary phone and dial the number. I honestly don't know if these were actual consumer devices or some sort of technician's/phreak's tool.
where there's fish, there's cats
For more information, I suggest reading old articles of Phrack.
What kind of a world do we live in where the most readily available information about an electonic device of immense historical importance is information put together by and for people who were outsiders trying to break in? Why isn't all of Ma Bell's old secret internal documentation out in the open where future generations can learn from it?
where there's fish, there's cats
I once read that today's phone system is still electrically compatible even with phones that predated dialers. If so, you could connect one of those old wooden phones from the 19th century with the separate microphone and earpiece. If you are skilled enough with rapidly toggling the hook, you could even dial numbers (you can try dialing that way on touch-tone phones too).
This is kind of off topic but I expressed a sentiment of this sort the other day.
We were indoors, but it was chilly. We had a logs, a starter log and even matches, but no one was really sure how to go about starting a fire in a fireplace.
None of us had ever really started a fire that wasn't a barbeque and we weren't sure how to go about checking the flue and such.
I found that really sad. I grew up a city kid and I was never a scout or anything. I've always lived or worked in buildings with central heating.
As technology has expanded, the knowledge of simple things dies.
I'm going to make sure I learn how to build a fire before the next week is out.
From 1978-1982 I worked in a Central Office in south Georgia that only supported Rotary (pulse) dial telephones (we even had "party" lines back then.) The reason was, the entire phone switching system was electro-mechanical. When you rotated and released the dial on your black or beige Stromberg-Carlson model 500 phone, an entire set of X-Y stepper switches, housed in a building the size of a small gymnasium, mechanically moved to complete the connection. The noise was unbelievable, >90dB at all times, and I have hearing loss to this day from my four years of working in that concrete building. When a backhoe operator cut a large cable somewhere, we immediately knew when there was about to be a lot of trouble tickets, because the sound of many banks of switches slamming shut simultaneously could not be ignored. I still love the old, heavy, tough rotary phones, because they are, in fact, a representation of the old, heavy, tough switch buildings that very few people have ever seen in action. For the most part, they're gone now, but once upon a time in technology, they worked extremely well. I'm fascinated by this retro curiosity in rotary dial handsets.
I distinctly remember seeing a rotory phone hooked up to an acoustic coupler in the movie. It had an automatic mechanical thingie that worked the rotory dial. Morpheus used it to hack into the Matrix!
The line to your house was probably fine - it was probably the telephone exchange equipment at the other end that didn't do touch tone. The odd Strowger exchange was still hanging on as late as the mid-90s as well as the odd Crossbar. Electromechanical switches just couldn't do it.
In Britain, there was a different problem - in the 1980s, many exchanges were electronic, but they couldn't do touch tone because of the frequency of the dialing tone (a 50hz purring sound at the time). It would have been easy enough to change the dialtone to the one we are familiar with today, but bureacratic inertia stopped it (We still have Strowgers and Crossbars - the dialtone must be the same over the whole country was the argument used). This eventually gave way when System X and System Y digital exchanges started to appear in the late 80s. System X and Y are still in use today.
After my grandmother died, I kept her 30 year old rotary dial telephone as something to remember my grandparents by. I obtained an original wall junction box for it and wired the RJ-45 plug to that instead of modifying the phone cord, so the phone is completely original. Still works like new.
Go to http://www.light-straw.co.uk/ for some excellent historic information on the British phone network. One of my favorite bits is the story from the international operator at Faraday House from the 1970s.
Oolite: Elite-like game. For Mac, Linux and Windows
Back in the days of 300 and 1200 baud (when baud actually meant baud, IOW) it wasn't that big a trick to fake a modem tone-- stupid human trick at best. You just had to whistle the right tone (an easy one to whistle for most). The trick was to simulate a Ctrl-C, which usually woke up the host on the other end, which obliged by spilling the logon prompt. A very very quick rise in tone and drop to the original got this done.
This is what Mitnick (and a few thousand others wanting to win a bet in a geek bar, myself included) learned how to do. When the audience was suitably drunk, the usual response was "Fuck! You speak computer, dude!" Where to pick up the skill? For me, the university I attended used to loan out portable/luggable 300/1200 baud TI printing terminals, thermal paper included. My rotary dial phone snuggled in the acoustic coupler just fine-- but you heard whistling while using it. A few hundred hours later, those tones were burned in your brain forever (I'm whistling the tones right now, lol.)
I have no idea how to make soap though.
This one I know (thanks to my chemistry teacher of long, long ago)
Animal fat and or oil, rainwater, ash and salt
Ash + hot soft water -> lye water
(you can use caustic soda instead, and generally do, but if we're talking survivalist I guess the assumption is that it's unavailable)
Note: lye water burns, so don't put it in anything that'll dissolve, drink it, bathe in it, etc.
Shove melted animal fat in water and remove the nasty floaty bits, add salt. You can de-stink the fat using sour milk.
Now: mix lye water and grease, boil out excess water, add salt, set it and let it dry.
Note: if you get the wrong quantities of lye water, the result will burn.
I recall we did this in class using caustic soda and synthetics, but our spoilsport of a teacher wouldn't let us try the resulting liquid goo on our hands. I have a hole in one arm of my lab coat from unofficial testing of the stuff (which looked like The Blob) so he may have had a point.