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This is a question DIY Techno-hacks

Old hard drive platters make wonderfully good drinks coasters - they look dead smart and expensive and you've stopped people reading your old data into the bargain.

Have you taped all your remotes together, peep-show-style? Have you wired your doorbell to the toilet? What enterprising DIY have you done with technology?

Extra points for using sellotape rather than solder.

(, Thu 20 Aug 2009, 12:30)
Pages: Popular, 9, 8, 7, 6, 5, 4, 3, 2, 1

This question is now closed.

Batteries not included...
My ex and I used to enjoy a fair bit of battery operated fun when we were at uni in Exeter. As you can imagine, horny students plus battery swallowing toys plus very limited spare change, (I was spending most of my money on my home cinema goodies and my 4x4 but thats for another post), meant that sooner or later the financial aspect would give us some pause for thought.

By this point we had built up a fair collection thanks to the Love Shack just off the main street. Great selection and the manager has a couple of really nice Kawazaki Z1300s there. I recommended it most heartily. Any way, we now had more toys than we were willing to fund and something had to be done about it.

"AHAR!!" says I, in fake piratey voice. "Maybe there's another way to shiver her timbers?"

So off I trotski to the Radioshack in the next street and pick up a mains transformer and a selection of mono head phone sockets and multiplugs... can you guess what it is yet?

Once I had assembled all my nefarious goodies I liberated a soldering iron from the Engineering block where I was studying and retired to my room for some serious Macgyvering in the pursuit of pleasuring the other half, (or 2/5ths as we calculated at one point).

Any way, after some time I emerge with...DEVASTATOR! Most powerful of all Shagobots, formed from the union of the Dildobots and capable of reducing a paving slab to gravel or a lusty student girl to squeals of joy in less than a second.

It basically consisted of an adjustable voltage transformer, adjustable from 3 to 15 volts with a single 3.5mm mono jack, like a headphone plug, as it's output. (Since most of our goodies ran at 3v to start with that gave us some extra power to really speed things up!)

That mono jack was then plugged into a four way adapter allowing a wide selection of the other toys that I had adapted to be run at the same time by soldering wires onto the motor terminals and then out of the casings and onto other headphone plugs!

WOOYAY!!! We now had almost limitless power and could run as many toys as we liked. Eggs, Butterflies, Dils, you name it. This earned me many brownie points for a while until we melted the motor on one of her toys.

Did I:

a: throw it in the bin and carry on with the others?
b: buy her another one as a present?
c: do what any self respecting engineer would do after blowing an engine and put a bigger one in instead?

It just so happened that our engineering set had just done a project on gyroscopes and balancing mechanisms and there were a couple of 15v R/C motors hanging about. R/C motors are the pumped up steroid versions of normal motors and are able to pump out stupid amounts of speed and torque without breaking a sweat....see where I'm going here?

It just so happened that one of those engines will **just** fit into the body of our newly deceased toy. With a new counter weight fitted, made of steel and profiled to give maximum weight and throw inside the body and with some padding inside to hold it all in position it was completed.

To lift a quote from the original movie:


Holy mother of all that is holy! Finally able to use the full 15v from the mains and with as much current as we liked this thing was truly animal. It sounded awesomely like a motorbike when at tickover or on full throttle. The howl it made when we cranked it up actually made my GF looked quite scared! She used it once and complained that a half speed it started hurting and at 3/4 speed actually left her bruised inside. I used it to bash a hole through a sheet of plaster board and we didn't really take it over a third of it's power after that. Like having a Bugatti Veyron though, it's not that you may ever use it's full power but it's nice to know it's there if you need it.

I miss those days...

Length: 10"
Width: 2"
Speed: 15,000rpm @15v
(, Sat 22 Aug 2009, 9:38, 7 replies)
DIY TV repair using the magical invention of Fire
When I was about 14, I had a ZX81 but no TV of my own. Then my step-mother bought me an old 22" black-and-white one from a jumble sale for 20p (wow! thanks!) and it worked very well for a while. I even modded in a switch and an earphone so I could watch it quietly at night.

Then, one day, poof. Magic smoke escaped from something inside and the horizontal scan stopped working. A single vertical line in the centre of the screen isn't very compelling viewing, so I opened up the back again but couldn't see anything wrong.

So I replaced the fuse and fired it up again. Bang. Dead. And again. Bang. Dead. And again. Bang. Dead. Something caught fire. Aha! At last I can see what the dead component is - it's the one that's alight.

It was a 600V paper capacitor, and I happened to have a replacement around, so I blew it out, let it cool, and fixed it. The set worked forever after until it was finally replaced with an Amstrad CPC464 and monitor.
(, Sat 22 Aug 2009, 9:37, Reply)
How to avoid typing in programs from books
A few years ago I had a very old DEC PDP-11/73 minicomputer dating from the early to mid 80s. It could boot off its 32MB hard disk, or from 8" floppies or RL02 disks - 10MB disk packs about the size of dustbin lids. You turn the power on, and it would display a big scrolly message indicating that it belonged to Aberdeen College of Agriculture, then a little "boot:" prompt where you typed the letter for the drive you wanted to boot off. After ten seconds or so, it would boot to DU0: which was the first hard disk partition. Great. Until the fateful day when one of the boot ROMs went phut. Arses.

Now actually booting the machine wasn't too hard - you could drop it into an octal debugger where you could program it by typing in big strings of numbers, rather like typing in programs from magazines in the early days of home computers. This got old pretty fast, though, because you needed to type in a couple of dozen four digit numbers *every time*.

"Hang on a sec", I thought, "this terminal I'm using has programmable function keys that can store sequences of keystrokes. Wonder how big a sequence it can store?"

Big enough as it turns out. So when my PDP11 was donated to a museum, along with all the manuals went a piece of paper describing which combinations of CTRL, SHIFT and function keys to press to send the magic words to boot it up.

I may have just out-geeked the whole Internet.
(, Sat 22 Aug 2009, 8:56, 7 replies)
May I just say...
WTF are you lot talking about?

Don't get me wrong, I've electrocuted myself many a time, taken a Big Trak to bits (and never been able to put it back together), and made plenty of makeshift electric motor powered lego cars, but when you start talking ohms, amps, and "32-D-tri connectors man!" I am lost.

Dumb it down a bit, for my sake please?
(, Sat 22 Aug 2009, 8:36, 3 replies)
Re sellotape, and diy.
Is anyone here old enough to remember the Leslie Judd/Val Singleton debate? For me, it'd be Val, all the way.
(, Sat 22 Aug 2009, 6:34, Reply)
Probably Stolen Laptop Hack
I picked up a dinky laptop for a song off of eBay with the knowledge that it was "broken" and wouldn't boot. It seemed that the BIOS was locked out and there was a system password (which was strange, but I didn't know it) so some swift Google-Fu demonstrated that you would need to short circuit 2 legs of an EEPROM chip on the motherboard in order to reset the ID of the system, and then you could enter a new one sans unknown password.

So, disassembling the beast I propped the bare motherboard up with the monitor panel sticking off of it and fired it up. It took some time, but I found a chip with the right lettering on it which was about 4mm x 2mm. At the right spot I shorted the pins and.... nothing. I'm nothing if not tenacious. I shorted different pins, made sure I was getting it right. Made sure the paper-clip could conduct electricity (discovered it could when I dropped the clip on the motherboard creating a few sparks and angry noises) and was stumped. I tracked down the chip manufacturer's papers and learnt all about the damn thing. I knew what voltages went were and what pins were dead pins with nothing going through it. Four days of study and frustration I sat looking at the board and realised. I was looking at the wrong fucking chip. The right one was under some black plastic. Ole! Shorted the correct pins on the first try - Unlocked laptop! Woo!

Put it together (with some screws to spare - buggered if I knew where they went). Upon boot it became apparent that the laptop was from some company which I imagine the machine was stolen from, but that's another story...
(, Sat 22 Aug 2009, 2:24, 2 replies)
Selective Genius
I am no good at mechanical repairs. However hardware or software repairs I am a genius at.

I can fix computers, sky boxes, software car updates, videos, electrical boxes, BT cabinets, tvs, all phones, watches, TV studio circuitry, servers, networks, hifis etc. Yet I have to call a dude to seal my bathroom.

Arse camels.
(, Sat 22 Aug 2009, 0:48, 2 replies)
Last year I accompanied
my mate to Harrogate to purchase yet another madcap Citroen project. This one was a long wheelbase Citroen CX Prestige. It had a paintjob that had been carried out by a blind arthiritic chimp, handled like a waterbed and the engine noise was syncopation that Scott joplin would've been proud of.

Anyway, we set off back to Hull and got to the York ringroad, whereupon his car stalled. He got it going again and we finally limped into the McDonalds carpark at Clifton moor.

We listened to the engine which was clearly not firing on all cylinders. The guy he bought it off had mentioned a repair on a HT lead. So we had a look and it had clearly been repaired by thoroughly ignoring it completely. The business end of the lead was almost non-existant. However, we managed to rebuild it using two paperclips and a McDonalds straw.
(, Fri 21 Aug 2009, 23:02, Reply)
The ZX Spectrum Laptop

I love making pointless electronic and mechanical devices. I did the souped-up toaster in newsletter 324, and above is the one I'm most pleased with so far, a Frankenstein-style combination of a Libretto and a ZX Spectrum. I haven't got around to loading a Spectrum emulator onto it yet but it will come.
(, Fri 21 Aug 2009, 22:04, 7 replies)
I tried to
take the IR filter out of a cheap webcam and replace it with a bit of (precision-cut!) exposed negative.

It doesn't work. I probably broke a wire or three. Sausage fingers are great.
(, Fri 21 Aug 2009, 20:42, 1 reply)
I had a forum question
which kept overloading with nerdy electronics stories. So I diverted a current of pure cuteness through it.

(, Fri 21 Aug 2009, 20:13, 1 reply)
Flag on a phone antenna
My part wasn't technical - I just used a flowerpot, a cuphook and some string.

Thames Water put an empty lamp-post up outside my house, so their water meter could get a cellphone signal. It looked so empty, I had to put a flag on it.

(, Fri 21 Aug 2009, 19:27, 3 replies)
I hacked that kittenify thing posted in last week's newsletter to get it to show puppies instead:

Change the bit of the bookmark address that says "photos_public.gne?tags=kitten" to "photos_public.gne?tags=puppy"

What do I win?
(, Fri 21 Aug 2009, 19:04, 4 replies)
The electrombrero
Made in time for Millennium New Years Eve:-

Take two old sombreros bought when on holiday in Spain with the school.
Add 32 LEDs around the rim (red on the red sombrero, green on the green one).
Add a PCB inside the top (above head level) containing four chips and a handful of other bits and bobs, plus a touch of programming.

Result: a pair of sombreros with a 64-pattern, variable-speed light chaser on each. Still got them. They still work.
(, Fri 21 Aug 2009, 18:06, 3 replies)
Another alarm one
Not content with my car alarm just making a racket if you broke in, I decided to add my own "enhancements".

Output normally used to flash indicators routed to a delay timer.
After a few flashes, delay timer would switch on.
Delay timer fed another siren. A LOUD siren. INSIDE the car.
Delay timer also fed a step-up converter that kicked out 500 volts AC to wires conveniently placed on the bonnet catch. A thief can't shut the alarm up without opening the bonnet, but can't open the bonnet unless he shuts the alarm up, otherwise he gets a belt off it.

I never felt the full force of this nasty beastie (although I did get a taster of it when testing the circuit, thanks to a wet soldering iron sponge) but one of my mates did when I asked him to pop the bonnet when the alarm was going off :-)

The 500V power supply is still lurking in a box somewhere...
(, Fri 21 Aug 2009, 17:56, 3 replies)
ALARM clock
Alarm clock not loud enough.
Removed sounder from an old car alarm, screwed it to the back and soldered it in.
Alarm clock now loud enough.
(, Fri 21 Aug 2009, 17:43, Reply)
I have a fuzzy memory of two seperate incidents when i was younger.

First one, back when video recorders at home were quite new. My father (and mother) are teachers, and would often set the recorder to record late night educational shows for later use at school.
Around this time I had a plasma ball. One with blue glowy strands that jump about and concentrate on your hand when you touch it.
Well one evening i was bored. I was playing with the plasma ball listening to trippy music, when i started touchingt he ball with just about anything i could find.
I used a 2p coin and got quite a spark. ooo... how pretty i thought. I kept playing with a coupld of coins and the plasma ball for some time, seeing how far / big a spark i could create.
Only a couple of days later did I discover that my father had been recording something that night, and that when ever i created a spark it fucked up the video recorder and essentially made the picture he was recording fuzzy and unwatcheable.
I think the show he was recording was the middle of the series, wasnt repeated for AGES and was completely unwatcheable!

Second one, horrible electronics class at school (i must have been 14 or so). We were split into pairs and given a board and plug and play components and a workbook. The idea was to use the plug and play components to create the most basic of electronic devices.

By accident I discoverd that if I shorted out my board, it made the group opposites short as well, or to them just go dead. I did this a couple of times to confirm my suspicion and the correlation between the two. By teh time I was certain they had called 'teacher', and for a good five minutes I managed to completely befuddle the teacher AND not burst out in huge fits of laughter, as tehy all got gradually more and more confused about what was going on.
(, Fri 21 Aug 2009, 17:29, Reply)
Post about toast reminded me of my unfortunate encounter with the toaster. Picture the scene, twelve year old girl putting some fruit toast into the toaster... Only for one slice to break in half and wedge itself at the bottom. Cue said girl sticking a metal fork into the toaster only to have her arm thrown from her body and the fork narrowly missing the dog.

Now, of course I promise that it wasnt me
(, Fri 21 Aug 2009, 17:10, 1 reply)
I tied all the remotes to the table-leg with string, does that count? It's fucking brilliant, you should all do it.
(, Fri 21 Aug 2009, 17:05, Reply)
my creativity knows no bounds
I made this for my girlfriend:

but she left it at mine and we've split up now. My plan is to wait til I've met someone new then after a few months give it to her pretending I've just made it :) I'm well crafty.
(, Fri 21 Aug 2009, 17:04, 10 replies)
Monging Mirror
A hard drive platter, slightly bent across the middle, makes an ideal "monging mirror". Look in it at the right angle and you'll see what your retarded twin would look like.
(, Fri 21 Aug 2009, 16:58, Reply)
i couldnt find a gamepad for my pc i liked
the majority available are either playstation pad knock offs (playstation pads make my hands hurt, too uncomforable) or just retarded

the solution: get a second hand xbox pad off ebay and solder a usb connector onto it

and i once made myself a wallet out of duct tape, it lasted about a year before it started falling apart and i couldnt be bothered to make another
(, Fri 21 Aug 2009, 16:50, 5 replies)
Not wanted to bin
a perfectly good dildo that Mrs SLVA had relegated to the back of the cupboard in favour of a lovely new rabbit toy, I gouged some of the insides out and fabricated an attachment that would allow it to be connected to one of these.


It had a stroke length of just over an inch and went like, well like a reciprocating saw with a dildo on it.

I suggested that we try it out. Did it work? I don't know, she wouldn't go near it. I spent all afternoon on that fucking thing too.
(, Fri 21 Aug 2009, 16:43, 4 replies)
Sorry but...
Its been a tough week.
For starters my dog decided it would be funny to piss in my bag. Everything was ruined... everything.
Then my Parents decided to do all of the decorating in the house the same week and everywhere was complete chaos. They couldnt agree on the colour scheme and ultimately decided that they were no longer getting on so have decided to get a divorce.

Two days later my gran died...
Then the internet stopped working
Then we got burgled and the bastards took everything
.. including the key to my locker.
Then I got swine flu and nearly died

... but despite all of this, here you go Miss, here's my Project, right on ti... oh
(, Fri 21 Aug 2009, 16:38, 2 replies)
I made this
well, actually, I bought the cabinet for fifty quid on ebay, renovated and refurbished it, and made it into this:

It glows in the dark, has over 3000 games, and is a magnet for the array of beer swilling animals who call themselves my friends (the top surface makes an ace pint shelf)

It's my new hobby, and it's great fun.
(, Fri 21 Aug 2009, 16:37, 8 replies)
The radio-controlled cat-flap-cat-box-cat-containeration device
We've got a kitten. He's a loon. He's also not yet safe to go out without experiencing instant death under the wheels of cars. He's a nippy little bugger so we'd have great difficulty getting out of the house without him racing through the door at the last minute, resulting in an hour or two chasing him about trying to get him back inside.

My solution was (not) simple:

Get one plastic cat box (the kind you take the cat to the vet's in).
Replace the little door with one of those catflaps that only open if your cat has an infra-red transmitter on it's collar.
Replace the electronics for the catflap's infra red receiver with the gubbins from a car remote central locking radio device.

Put kitten in box (the catflap will open inwards but not outwards).
Leave house.
Close door.
Press button on central locking remote key fob.
Catflap then opens both ways.
Kitten gets out through catflap and runs up to window to shake paw at you through the glass.

Sadly, we've not managed to come up with any way of putting him back in the catbox prior to us coming back in, but usually he's too slow when we return.

Here is peanut, looking evil:

(, Fri 21 Aug 2009, 16:29, 1 reply)
Speaking of fuses
Not me, but a mate™, had an amplifier and took the lid off to tweak the potentiometers in it to up the power or something. Personally, I think he just liked pissing about. Anyway, so the routine was switch it off at the mains, tweak the pot, switch it back on and test it, repeat. He then noticed the internal fuse and by removing that, it saved him having to walk the 3 paces to the wall socket.

He managed this routine another 3 times until while poking about he suddenly lurched backward and did the best impression of a lion's roar I have ever heard. It turns out he had shorted the internal fuse teminals with his thumb. Oddly, it made him gums bleed and then he stood there and giggled for a good 10 mins.
(, Fri 21 Aug 2009, 16:29, Reply)
one for the darwin awards, perhaps
working in construction, and specifically in internal refurbishment programs for various local authorities, we come across our fair share of complete and utter fucking idiots who occupy the properties we work in from time to time.

my boss tells me of a time when he visited a run-down council house to carry out a pre-works survey on. upon entering the house he was amazed to see no less than 8 or 9 different appliances all connected in to one plug socket via a complex system of double adapters, triple adapters and extension leads. the TV, video player, radio, electric heater.. everything, all going in to one plug socket.

"how the hell does the fuse not blow on all that then?" he enquired.

"ahhhhhh" said the scummy tenant, looking quite pleased with himself. he was obviously glad that my boss had asked.

he then proceeded to show my boss how he'd replaced the fuse of the extension cable which connected the whole lot into the wall... with a screw.
(, Fri 21 Aug 2009, 16:26, 1 reply)
Telly power switch
Years ago the power switch on my (already ancient) portable telly died. It was a 1990 model Goldstar, better know as LG these days, and the buggers had used a bizarre power switch that combined a toggle switch that turned on the HT power supply for the tube and a momentary switch that fired up the tuner.

Could I get another switch the same? Of course not, they were custom Goldstar switches I was told by the 'expert' at Maplin, so I pondered it for a moment and decided to buy a chunky metal toggle switch and a push button, and wired them up in its place. I made holes for them on the side of the case using whatever tools I had to hand (shit drill and a kitchen knife I think), and then taped the wires from the old switch into the new ones. And then added more tape. Then a bit more tape. The bastard thing is still working =)

(, Fri 21 Aug 2009, 16:20, 3 replies)
I want to...
... connect music and video to different rooms of the house using bits of copper wire and blu-tack.
... electrify my doorbell so it zaps anyone stupid enough to ring it between 1am and 5am (except at the weekends).
... add exciting gadgets to my guitar using tinfoil and the insides of a christmas cracker

just like all the other people here. As it is, my most exciting DIY hack to date is that, for want of a soldering iron, I clipped the wires back on the speaker of my bass amp by squeezing them together with some bits of tin foil. This was 8 years ago. I bought a soldering iron at least 5 years ago, and didn't get round to finishing the job. Still works though.

Oh, and I have an S-Video to Scart cable, and I used two little bits of tin-foil to make it go into colour instead of the black&white image I was getting before. Now we can play Warcraft 3 on the TV!
(, Fri 21 Aug 2009, 15:43, 2 replies)

This question is now closed.

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