Since the last post, I’ve rebuilt the bed (replacing all the chipboard with plywood) and done a lot to the electrics.  This photo also reminds me that I need to find my stock of rubber feet to pad out the front edge of the under seating storage access hatch so it’s level.  I might go do that now.

The grey box top left is a 5V PSU with two 7805 regulators in it.  It’s got a USB socket which I had hoped I’d be able to use for charging things, but I’d forgotten that you need to muck about with the data lines on the USB socket to get that to work.  My big box of resistors doesn’t have the bits I needed in it, so that’ll have to wait wile I put my next component order together.  For now though, it’s quite happy powering the computer speakers I’ve got for listening to podcasts in bed…

As well as the USB socket, there’s a 2 pin din plug which is used to power the LED spotlight shown above which I got from Ikea.  It makes for a great reading light.  It consumes about 500mA though, which is quite a lot if you ask me!

I’ve replaced the bank of batteries pinched from one of my phone exchanges with a leisure battery, there are now 4 individually switched and fused circuits (all of which go back to an isolation switch and another fuse)

The big cable coming off the battery goes via a fuse and then heads off down the van towards the engine bay.  It doesn’t quite reach the engine bay as yet, but when it does so it’ll hook up to a split charge relay so I can charge the leisure battery while driving.  At the moment though it only makes it as far as under the drivers seat.  Getting any further needs me to take the floor up in the cab, but I need to drive the van tomorrow so that job will have to wait as well!

If anyone else is doing something like this, it seems the cheapest way to buy big enough cable for a split charge system is to buy a set of extra-long jump leads.  The ones I got are rated for 800A, were 6m long (giving me 12m of cable to play with) and came in at about the same cost as 3m of similar cable bought off the reel.

Ian, Chris and I went to the NVCF last weekend.  It’s a bit like a combination of a specialist antiques fair, a car boot sale, and the contents of your grandads garage.

As well as all the old radios, televisions and telephones, there was a selection of test gear with amusing manufacturer names. Pfft! Wayne Kerr!

I was called over to one stall to try and identify this piece of equipment.  It was apparently recovered from a BBC building somewhere, and it’s an optical disk player.  The disk has sound encoded on it as a black line of varying width.  There’s a lamp on one side and a photoresistor on the other.  When the disk spins, the amount of light falling on the photoresistor changes the current passing through it, giving you audio.  It’s only got one disk, although it appeared to have several (5?) messages recorded on it.  The photo detector didn’t appear to move though, so I think changing messages was probably a manual operation.  These machines were often used to play back messages like “all lines to London are currently engaged” or similar messages.

I didn’t get any closer to identifying it, and whilst I was intrigued by the message it might contain – I wasn’t intrigued enough to find space in the car for it.  Besides, Chris had filled most of the car with radios by that point!

I managed to spend about a tenner and got various bits and bobs including this clock unit.  The displays are interesting.  They’re a stack of plastic laminates, each one has a numeral engraved on it.  Each laminate has a lightbulb which illuminates it from the edge, causing the numeral to glow.  It’s quite clever, and undoubtedly pretty.  It’s a bit tricky to drive with modern technology (and where’s the fun in silicon anyway?!) so I’m going to build a clock out of uniselectors to drive it instead.

I think I can get away with 1 uniselector for the hours (using 24 outlets of a 25 outlet uniselector, with two banks driving both digits and a third bank which can be used to skip the last position) and two uniselectors for the minutes (one per digit, each with 2 banks.  One to drive the display and the other to skip unused positions) – the circuitry to step the uniselectors once a minute should be fairly straight forward.

It would be easiest if I can generate a 1 minute pulse from somewhere, but I’ll probably drive it with a 30 second pulse so it’ll be compatible with a GPO master clock if I ever get one!

Along with the associated relays, that should all fit nicely in a box underneath the display.

Great.  I needed a new project…

Blimey I’m behind with this one!  The weekend before last, I went to the Dean Forest Railway Thomas Day.  It was a fun day out with my niece, nephew, sister and her hubby.  Thomas himself wasn’t as photogenic as I’d hoped, but I liked these shots of 9681 (or whoever 9681 was pretending to be)

For me, the highlights of the day were the story we had read to us as we went up the line from Norchard to Parkend on Daisy the DMU, and the diesel stealing Thomas’ carriages while he dozed off in the station.  The fat controller waking Thomas up with a bucket of water was hilarious.

Back on the 13th April – the Saturday of this years BJC – Charlie, Emily, J and I went for a ride on the North Yorkshire Moors Railway.  It’s taken me ages to get around to processing the photos, but here they are..

There are some also rans in this months album, but I think I probably overcooked the post work a bit.

It was the THG Swapmeet at Avoncroft museum of historical buildings today.  I didn’t take much with me to get rid of this time (partly because I’ve got rid of a lot of stuff already, and partly because I was too lazy to organise getting rid of anything) but I came back with a pile of books, some posters, a Buzby tea tray, a box full of useful krone spares for the railway (including some test leads which should make verifying anything we do much easier) and most of an AT&E Type 6 phone.

I’ll write up more about the phone some other time, but I’m dead excited about it – because it’s the phone which would have been supplied with my small PAX (and probably my larger one as well, but I can’t find any documentation to confirm that) - I’ve been looking for one for almost 3 years now and have at last managed to find a base, dial, and handset.  I’m missing the case, but I can probably modify a 706 case to fit, which will do until I can get the “right” case) If anyone has one lying around they’re willing to part with, I’d love it!

Yeah, I thought not.

Also happening at Avoncroft today was some kind of civil war re-enactment.  The avoncroft website says:

Experience British troops of the 1770s drilling and making ready to take control of the rebellious American colonists. The Lexington Militia will try to prevent the redcoats from searching their homes and town. Will King George’s army be able to keep control?

But I could have sworn the lady said it was described as “the last English civil war” – although, I suppose the begining of the war of independance could be thought of as an English civil war.  Still, they looked jolly dangerous with their guns and whatnot, even when they were just chilling out with their ladyfolk!

I had a bit of a poke around Avoncroft as well while I was there.  They’ve got a lot of buildings, and I’ve seen some of them before – but have never explored properly.  They’ve got some dead good stuff!  My favourite was probably the ice storage house because it was dark and echoey – unfortunately it doesn’t photograph very well, because it’s just a circular brick chamber with a lot of insulation.  The windmill made up for that though…

Their prefab house was amazing (I really wanted some old guy in a cardigan to sit in the chair for me to take photos of, but there wasn’t anyone suitable around, and you could only view the rooms from the doorway anyway) but their prefabricated church was just as ace, and much easier to photograph!

While I had my camera out, I also took the time to sit down for 10 minutes, have a good think about my surroundings, plan a photo, and then shoot something for this weeks photo-challenge.  It was this gnome.  I rather like him, and am quite please with the wonky breaks-most-of-the-rules composition.

Just a minor alteration to BOV today, I picked up a cutlery holder from Ikea today.  It’s the right size to hold a phone/ipod while it’s on charge (or playing mp3s) in BOV.  Of course, it’ll be more useful once I’ve got a leisure battery rather than a bank of batteries raided out of a redundant UPS :)

Pre-Christmas interior:

In September, I fitted a sink/cooker unit, and took BOV to the Bristol Juggling Festival.  Just for one night, but that was enough to get stuck on the field and needing a bit of help to get off it again.  Note to self: find some planks from somewhere to park on next time I’m on grass.  The sink had no plumbing, and there is no gas supply to the cooker yet.

Misc Mechanical:

I didn’t do much to the van over the winter, and then in the spring it needed a bit of TLC to make it roadworthy.

• Nice big new battery fitted
• The fuel pump seized because I left it 3 months without starting the engine.  I spent a lot of time on this one before I gave in and called out a mechanic.  He knew what to hit and how hard to hit it, and we got the engine started again.  Note to self, start the engine at least once a week over the winter!
• BOV has made it through its MOT, with a small amount of welding, a new wiper blade and a lot of work done on the brakes (a new calliper, new disks and pads, and a new handbrake cable)

Internals:

Once it was through the MOT, it was back to working on the interior.  The L shaped bed design turned out to be problematic.  The loose chipboard covering slid all over the place when driving, and with the sink unit in place it was near impossible to pull the slide out section into position.  So, with 2 days to go before the BJC I tore it apart, and converted it to a C shape.

This layout means that the pull out section is a lot shorter and easier to handle.  By cutting down the chipboard I was able to add some hinges, creating some hatches for storage under the seating – securing the chipboard from sliding around in the process.  There is still room for improvement though, as the slatted pull out design means that the long side of the C can’t be used for storage in the same way as the short ends.  I need to think of a way around that.

I’ve plumbed in the waste pipe for the sink, and that now exits the vehicle via the wheel arch.  I need to get hold of some flexible hose before I can make that useful though as at the moment it’ll drain water right onto the ground in front of the driving wheels – which is somewhat detrimental to my ability to get off a muddy field.  A drain hose from a washing machine looks like it should do the job easily enough.

We needed some electrical supply before BJC for important things like charging mobile phones, or listening to podcasts on powered speakers.  The easiest way to do this appeared to be with a bank of batteries pinched from one of my phone exchanges stowed under one of the seats, hooked up to a cigarette lighter power supply bought from Halfords for not much money.  It’s wired through a fused switch (fused at 3A) so I can easily isolate the batteries to ensure nothing is left on during the day to run the battery down.

An adaptor plugs in to give a regulated USB supply, although in time I intend to build my own regulated 5V supply which will run some LED spotlights I’ve got as well as a USB charging system.

There’s no provision for a split charge setup yet, but I do have a small solar panel to top up the batteries a little.  The phone exchange batteries aren’t the best choice (as they’re not deep cycle batteries) but I’ll replace them with a leisure battery as soon as I find one suitable at a reasonable price.  I also want to add a meter so I can check battery voltage without having to dig out my multimeter.

Lastly, since BJC I’ve added some cup hooks so that I can hang up a selection of enamel mugs.  There are enough mugs there to fully populate the seating with guests and offer everyone tea and biscuits in an appropriately civilised manner.

What’s next?

Before I use BOV for the Bungay festival, I intend to sort out the last bit of the seating so that I’ve got somewhere easy to store the duvet during the day.  I’d also like to build some sort of full height storage system at the back of the van (which will close off the gap in the doors, provide some storage in the living space for clothes, and storage behing the unit, accessible from the back doors for things like tools/jump cables, parking planks, waste water tank, misc stuff that needs to be kept but doesn’t need to be kept in the living space.

If I get time, I’d like to fit a split charge system and a leisure battery and wire in some permanent lighting.  I also want to fit kickboards to the under-seat area to tidy it up a bit, and make the storage more useful.

Once I’m happy with the layout of the inside, all my dodgy woodworking will get a rub down and some wood filler added to close up any gaps.  I’ll then give it a couple of coats of gloss or something to tidy it all up.  That’ll probably be after bungay though so the van doesn’t stink of gloss paint all week.

Siteswap is a mathematical notation system for juggling patterns, where a string of numbers represents a sequence of throws.  Each number determines how many beats later the object thrown, is to be thrown again.  There’s more mathsy detail than you ever wanted on the wikipedia page: http://en.wikipedia.org/wiki/Siteswap or you can watch this youtube video for a reasonably clear explanation:

Suffice it to say, not all strings of numbers are valid juggling patterns.  Some strings of numbers, if you were to try to juggle them, would result in two balls langing at the same time in one hand, or a ball needing to be thrown from a hand which is empty because no balls arrived there in time to be thrown.

So you need some way to check a string of numbers to see if it’s a valid siteswap or not.  There are various ways to do this by hand, and various people have written software to do it for you.  Every so often, geeks get hold of the idea and do things like “write the shortest possible siteswap validator in perl” I think the record for that is currently 28 characters:

1/grep$a[($_+$i++)%$.]++,<>

Recently Vakor posted that he’d built a regex which validates a siteswap.  This has been attempted in the past, but previous versions used a chain of several regular expressions and required the siteswap to be repeated in the input.  So I was impressed that he’d managed to do it in one shot – even if the regex is “unweildy” to say the least!

Anyway, all of this combined with me sinking my teeth into asterisk recently made me think I should have a crack at writing an asterisk macro which can validate siteswaps.  So that’s what I’ve done!  If you’re interested in the code/samples you can download it from http://paulseward.com/downloads/siteswaphone-1.0.tgz and if you want to play with it – you can call it on 0117 9115202 (or +441179115202 if you’re outside the uk and feel like paying for an international call)

If you’re not a juggler and just want to hear what it does, 97531 is a valid siteswap, but 97532 isn’t.

There’s no real phone on the end of it or anything, so feel free to call it day or night.  It can only handle one call at a time (because I’m too cheap to pay for multiple incoming lines for a toy like this!) so if you get busy tone, just try again later.

Let me know what you think, in the comments.

J and (no so silent) Bob the Dog are staying with me this weekend, I took Bob out for a nice long walk this morning, and he picked up a stick.  Usually I can persuade him to put a stick down, but he was more than a little keen to hold on to this one despite it being more of a log than a stick.

In other news, BOV failed it’s MOT yesterday mostly on various faults with the brakes, but also a bit of welding needs doing around one of the front suspension mounts.  So it’s booked in for that on Tuesday…

My Dad gave me his old Gillette 195 “fatboy” adjustable safety razor today.  According to the date code on the bottom (F4) it was manufactured in Q4 of 1960.  I’ve been shaving with a safety razor for a couple of years now (in between beardy periods) and have been truly won over from disposables/modern razors.

They may only use one blade at a time rather than the 5 blades the “Gillette Fusion” or the “Wilkinson Sword Hydro 5″ have – but I consistently get a better shave with a safety razor, I find them more comfortable to use, and the blades work out cheaper than modern cartridges or disposables so I can’t really see a reason not to use them.

At the time of typing this I have a full beard, but it’ll be gone by tomorrow morning.  All courtesy of a 53 year old razor.

As a bonus, it came with a Gillette Blue blade.  I don’t intend to use that for shaving (as it’s clearly been used) but I do intend to use it to build a foxhole radio. Which I’ll post about when I’ve done it!