Back in 2000, a couple of THG members got together and produced the TIM2000 speaking clock. It’s been out of production for a number of years now, and when examples do come up for sale they’re expensive (reflecting both the rarity and the high cost of the original device!) It also uses the MSF radio time signal to set its clock, which isn’t so reliable in much of the UK now that the transmitter has moved to Cumbria.
Technology has moved on, and a few people are planning on having a go at making a TIM2012 (or more likely 2013!) equivalent version with a modern microcontroller at the heart of it. PICs and dev boards like the Arduino have made microcontrollers more accessible and easier to program. Modern storage has come down in price a lot, so where the original used an eeprom to hold the audio samples we can now make use of SD Cards etc – the gubbins for interfacing audio onto a telephone line is easy enough.
Because the storage is removable (and huge!) We’ve got the opportunity to do cool stuff like offer multiple voices, allow people to easily record their own voice etc! Lots of possibilities.
I’m a bit excited by the idea so I’m diving in to see if I can swim anywhere.
I’ve bought myself an Arduino Wave Shield to go with my Arduino and have a play with with as a prototyping tools to see how close to a proof of concept I can get. I spent about 40 minutes putting it together this evening and have yet to play with it.
Word on the street is that the libraries recommended for use with the Wave Shield (for handling playback and all that) are a bit heavyweight and might not fit in the ATmega 168 I’ve got, so I’m going to either have to cut down the library size somehow by getting rid of the bits I’m not intending to use, or suck it up and upgrade my ATmega168 to an ATmega328 – which will cost me all of £2.20 (not sure I can stretch to that!)
Anyway, if I can get any of this to work, I think it should be possible to prototype up a TIM2012 for about a third of the cost of the original production model, and if it goes as far as designing a PCB I think we can get the price down to about a third of that again.
I’ve been obsessed by this juggling trick on and off since I first heard about in it the early 1990s. I’ve seen many descriptions of the routine, but very few are more than a couple of paragraphs long and the two examples in this post are about as detailed as it gets.
I’ve tried to learn parts of it over the years, initially with glass bottles (broke a few too many of them) then I tried a Bar Flair bottle (which has no “punt” on the bottom of the bottle making Trick No 4 as described below much harder) a few years ago a woodworking friend of mine, Duncan Hoyle made me a wooden practice bottle. It’s perfect!
I still can’t do the bloody trick though and it drives me mad.
Plate and Bottle trick, as described in “The Art of Modern Juggling” by Angela J Horton & James J Middleton, reproduced in Issue 14 of “The Catch” Summer 1995 (Page 17)
Plate and Bottle trick, as described in “New Juggling Tricks” by Ellis Stanyon (1901) – reproduced in 1978 by Roger Montandon, and reproduced again in “Manipulative Miscelania” by Reginald W. Bacon (Page 51)
Recently David Cain pointed me at this video containing some footage of Tommy Curtin performing this trick (Tommy’s act starts at 3:05ish) and while only one of the 6 tricks is shown in the video, David assures me that Tommy performs the full thing! If anyone knows of any video of Tommy performing this routine I would *love* to see it!
Spurred on by all of this, I plan to start practicing this routine again. I’ve found my wooden bottle, but unfortunately I can’t find any of my practice plates. Quick! To Ebay!
My description of priority calling in yesterdays post wasn’t quite accurate. I’ve dug out the Operational Bulletin and checked. It says:
3.4 Priority Service
An official having this service may speak instantly to any extension on the exchange, whether the extension is already engaged on a call or not.
The caller dials the required number and the Link Selector wipers extend the call to the required line.
If this line is free the bell rings and the called extension answers. If the called line is engaged no Busy Tone is heard and the caller is instantly switched into the existing conversation.
The call at this stage is not private; when privacy is required both engaged parties must replace their handsets, ringing current is then automatically connected to the required party’s bell and the call proceeds in the normal manner.
The circuit diagram notes say this:
7. Priority Facility
The priority facility enables an extension to speak to an engaged extension when the line that is dialed is already engaged.
An extension line with priority has tags K and PC strapped on the tagblock. On completion of dialing the two digits, relay G operates if the line is engaged.
Relay G operated:
G5 completes a circuit to operate relay E (NEG. 800E, C2, G5, (TL6) (NPB) S1, T1 & 2, U3, FS bank tags PC to K, K2, L1, FS (P) bank, U27, B6, T9 and 10, POS)
Relay E operated:
E1 completes the circuit to operate relay D (NEG. 200D, 500YB, G3, NR1, E1, B1, POS)
E4 disconnects Busy Tone from the calling line.
Relay D operated:
D2 & D3 complete a speech circuit across the called extension lines and the caller can speak and hear.
If required the priority extension may request the extensions to clear the call in order that he may speak in secret to the required party. In this case on the line circuit of the required line being restored, NEG is replaced on the PN wire from 1300K, in the line circuit and relay H is now operated from (NEG, 1300K, PN bank, 900H, C7, E2, NR4, N2, B1, POS)
Relay H operated:
H6 releases relay G followed by relays D and E.
With relay E normal, ringing current is connected to the called line at E3, and the call proceeds in the normal manner.
So that’s how it’s supposed to operate. How does the modification I’ve got change this operation?
This diagram should ideally be read in conjunction with the original diagram – as the diagram above doesn’t show the whole circuit, just the PC modifications (with a few relevant bits of circuitry just so you can orientate yourself on the main diagram!) As far as I can tell, the new sequence of operations is:
Relay PC operates:
PC is operated as follows: (NEG. 2000E, (TL6) (NPB) S1, T1 & 2, U3, FS bank tags PC to K, K2, L1, FS (P) bank, U27, B6, T9 and 10, POS)
PC2 completes a circuit to operate relay E (NEG. 800E, C2, G5, PC2, (TL6) (NPB) S1, T1 & 2, U3, FS bank tags PC to K, K2, L1, FS (P) bank, U27, B6, T9 and 10, POS)
Relay G operated:
G5 completes a circuit to operate relay E
Relay E operated:
E1 completes the circuit to operate relay D (NEG. 200D, 500YB, G3, NR1, E1, B1, POS)
E4 disconnects Busy Tone from the calling line.
Relay D operated:
D2 & D3 complete a speech circuit across the called extension lines and the caller can speak and hear.
If required the priority extension may request the extensions to clear the call in order that he may speak in secret to the required party. In this case on the line circuit of the required line being restored, NEG is replaced on the PN wire from 1300K, in the line circuit and relay H is now operated from (NEG, 1300K, PN bank, 900H, C7, E2, NR4, N2, B1, POS)
Relay H operated:
H6 releases relay G followed by relays D and E.
With relay E normal, Int Ring Tone is connected via PC1 to the called line at E3, and the call proceeds in the normal manner.
I have no idea why you would do this.
Int Ring Tone isn’t designed to ring a bell (it’s a tone!) and as far as I can tell, the only conditions under which PC1 is operated are when the called party is off hook – so I’m at a complete loss as to what this mod was attempting to achieve. Having documented it thoroughly, and spent a number of hours headscratching trying to work out what it’s for… I think I’m going to declare it useless and reverse the modification.
The cookies are based on the recipe from page 152 of The Cuckoos Egg (does that score some geek points?) I had to adapt the recipe a bit because as written it would appear to make 70 cookies (a few too maney for me!)
It’s been over 6 months since I last updated on this project, which is a shame because I’ve done rather a lot since then!
Apologies if you’re one of my non-telephone readers, this probably isn’t going to be a very interesting post, and it’s rather long. I’ll make up for it by trying to go for a photowalk tomorrow or something.
February:
The biggest bits of progress in Feb were that I started fitting the TL (Tie Line) relays to the selectors, and built an asterisk VOIP server. The two projects are linked in that the TL relays are needed to allow me to call through my PAX and into my asterisk server. I did actually blog about the TL relays at the time, but I don’t appear to have mentioned asterisk here before.
While I did most of the modifications to my first selector in Feb, it didn’t work.
March:
March was a productive month. If you look at the selector which is 3rd from the left in the picture up top, you’ll see it’s got an extra relay. This appears to be a non-standard local modification from when my PAX was in use at the Ffestiniog Railway. I spent some time in March mapping out what it does.
It appears to be related to the Priority Calling feature these exchanges have. If I’ve read it correctly, it works something like this:
Alice is in conversation with Bob, but Mr Miggins (Bobs manager) wants to talk to him urgently. Mr Miggins has Priority Calling set up on his extension (because he’s a bigwig!) and dials Bobs number. Bob and Alice get interrupted by a bust of ring tone to signal that they should end their call immediately and hang up. When they hang up, Bobs phone rings and Mr Miggins can tell him off for flirting with Alice on company time.
In its original form, the circuitry connects Bob and Alice to ringing current (designed to ring a bell), but with this modification it connects them to ring tone instead (the sound you hear when a phone is ringing) I’m not entirely clear why this is useful, or why it needs a relay to achieve this!
Also this month, I bought a BT Voyager 220V adsl router from a car boot sale for £1. I reconfigured it to work as an ATA and give me a phone on the DFR telephone network. I did start writing up how to do that, but it turns out not to be all that easy to describe. I’ll come back to it at some point as ATAs usually cost around £30.
I cleared a load of faults on the selector I’d modified (FS2), learning a lot in the process
April:
FS2 developed a release fault, which means that at the end of the call, the selector didn’t restore to normal but instead got stuck. There are some clever widgets called “heat coils” which stop things from catching fire when this happens. Here’s a picture of them on the PAX:
and here’s a closeup of one of them:
They have a pin (on the right of the picture above) which is held in the body of the heatcoil with a drop of solder. The idea is that if the release magnet gets held on the current flowing through the heatcoil causes it to heat up, melting the solder and pulling the pin out. The mounting then springs apart, earthing a contact which in turn lights the alarm lamp so you’re alerted to the fault.
Heatcoils appear to be next to impossible to get hold of, so it’s a good job they can be repared by carefully pushing the pin back in with a hot soldering iron.
May: I didn’t get anything done to the PAX in May, probably because I was rushing around like a mad thing trying to do up BOV and then I switched everything off and went on holiday for 2 weeks.
Actually, I tell a lie. Looking at the svn commit messages, May was the month I got my asterisk server talking down a SIP trunk to the server at the railway. I can now call from my office at home, through my PAX, into my asterisk box, through the internet to the asterisk box at the railway, out into the UAX13, then out through a junction and a few miles up the road to a PABX4 and listen to the test number.
Which is nice.
June:
I came back from holiday, built a charging unit for the PAX batteries – then switched my asterisk server back on, only to discover that it wouldn’t boot.
I decided to leave phones alone for a bit and work on BOV instead.
July:
I traced the asterisk fault to a dead compactflash card, so I resorted to old fasioned spinning hard disk instead (so much for low power consumption!)
This was a pleasing experience, because 95% of the config for the server was in svn so it was dead easy to reinstall everything and get back up and running. I did identify a few things that weren’t in svn and documented them in the form of a shell script – and checked that in to svn. Sure it’s not quite puppet like I use at work… but it’s better than nothing.
I then turned my attention back to FS2 which was still causing problems.
My paper exchange diary shows lots of slow, careful, methodical troubleshooting (cleaning contacts, adjusting spring sets, that sort of thing) – eventually resulting in me realising that white heatcoils are no good, only green will do – and declaring FS2 successfully modified – a mere 5 months after I started. “must do better” I thought.
August:
I started adding the TL relay to FS3. Managed to get all the wiring done in one evening! It took me almost 6 hours, and by that time it was too late to be testing it incase the rattling/swearing woke up the neighbours.
Needless to say, it didn’t work first time – and had a really odd fault. Dialing 50 caused the line circuits for 63 to pull in and you end up back at dialtone – which allowed you to dial another number! That’s not right at all! I checked all the new wiring and it was fine.
*scratches head*
Purely by chance, during one test I noticed that one set of wipers was horribly misaligned and was shorting out all sorts of stuff it shouldn’t be! I realigned the wipers and it worked! Yay! I now had 3 working TL selectors!
High on my success, I tidied up the 50 pair tie cable on the back of the PAX, fitted a battery isolation switch, tidied up all the mains cabling for the asterisk/charging circuit etc then set about adding a tie line relay to FS4.
That went much better. Having learnt from all my previous mistakes, it only took about 4 hours to wire it all out and it worked perfectly first time.
2012/08/12 – a year and a day after bringing the PAX home from Ffestiniog it had 4 working TL selectors. I did do a bit of a happy dance in the front room, and the cat gave me a dissaproving look.
But wait! There’s more!
I added a speaking clock to my asterisk server, with the voice of Pat Simmons. Pat was the second voice of the GPO speaking clock in the UK from 1963-1985 (the first being Ethel Cain, from 1936-1963) – I’ve started to build something similar with Ethel’s voice, but suitable recordings don’t appear to be easy to come by and I’m missing a lot of numbers – and crucially the “o’clock” sample.
I’ve also ordered a “Wave Shield” for my arduino with a plan to prototype a hardware speaking clock. We’ll see if I get any further with that than I have previous arduino projects. They tend to fall apart when it gets to writing the software – I lose interest because it becomes too much like my day job ;)
Today:
Todays *major* excitement was that I went to a car boot sale, and bought these for £3
They may look like a pair of long nose pliers to most people – but they’re BT /GPO “81′s” (or “Pliers, Wiring, No2″ if I remember correctly, they’re usually just called 81′s) and they’re the *right* pliers for working on telephone equipment.
I’ve been looking for a pair for about 2.5 years and I’m absolutely stoked that I’ve now got some!
Last weekend J and I went to a model engineering fair. It was *awesome*!
3 sports halls full of working models of everything – including trains of all sizes, jet engines, articulated lorries, aircraft, traction engines, buildings, musical instruments, fairground rides, electric trams… too much to mention. Bloody marvelous! So many model engineering companies there as well selling tools and materials it was a bit bewildering. I managed to use that as an excuse to keep my wallet in my pocket (I don’t have space for a milling machine anyway)
That train there is “T-Gauge“ (1:450 scale) which means the track is less than 5mm wide! There’s no way I’ve got the patience (or the eyesight) to model at that scale…
I didn’t take many photos (I’d only taken the compact camera with me, and it doesn’t do all that great with sports hall sodium vapour lighting) and these three are the only ones which worked out ok. I do like the one of the gallopers though. Really not bad for a compact camera with no tripod, propped up on a railing.
That’s that catchup out of the way, there will be a telephone related one along later…
That snippet of an article up there is from a juggling magazine called “The Catch” (Issue 11, Winter 1995) and describes a juggling club made by Freaks Unlimited in the UK in the early 1990s. Called the “Jester Club” they only made about 100 of them (and probably didn’t sell all of those!)
Well, 20 years on and I find myself in the strange position of wanting to get hold of one!
I’ve been in touch with Paul from Freaks Unlimited and he doesn’t have any lying around. I didn’t buy them at the time, although I can clearly remember seeing them in the shop. I’ve tried asking the joke shop in Bristol who took on much of the Freaks Unlimited stock when they closed down, and they gave me a slightly odd look and tried to sell me a fake dog turd instead.
So do you have any of these in the back of your cupboard? If you do… please get in touch via the comments!
For the first time in ages, Jonathan and I went for a photowalk at lunchtime. He’s got a new camera, and I needed a break from swearing at a web server which wasn’t playing as nicely as I felt it should be.
The shot of the grass at the top of the post is mostly there to compare with the version I shot on Jonathans new camera (once he develops the film)
I think there’s a shot to be had here somewhere, I don’t think this is it. I think at dusk, after it’s been raining, possibly with a person riding a bike towards the camera.
This weeks photo-challenge is “Sport” to coincide with the olympics. I’ll put my hand up to leaving this a bit late. I didn’t even try to take a photo until Sunday, and to be honest I spent a long time not getting very far! I tried 3 golf courses, 2 cricket pitches, a couple of rugby pitches and a football pitch – and found *no one* playing at any of them! The best I managed on Sunday were a slightly naff photo of a jogger and the above shot of an empty golf course.
Tonight however, I did a late night mad dash up to a couple of 24 hour squash courts I happen to know the door code to. It didn’t look quite like I remembered it inside (The changing room is smaller, and actually not quite as grotty as it was in my head) As I’m not entirely sure I should have access to the building, I didn’t want to attract any attention by using flashes or owt, so these photos are all lit by a torch and a 10 second exposure.
I’m not sure which of these photos is going to be my entry to the challenge yet, but it feels good to have actually got out and shot something. It’s sparked a few more ideas for the squash court as well, if I can find a suitable model.
Edit: On second thoughts, not the one of the squash ball - it’s not of the same standard as the other two from tonight…
