Thursday, 28 May 2015

Modelling in 3DS Max - getting started

After commissioning some disappointing custom 3D models, we figured it was time to knuckle down and give this 3DS Max thing a go. Our electronic board game is still on a back burner, but smoldering along - this time we're looking at creating some fantasy football teams (and considering making some custom animations using a Kinect for mo-cap but more on that in the future!)

Our original commission was for a couple of human footballers and a couple of orcs.
The initial photos came back looking like one character had been created, then simply re-shaped and re-skinned to create three other derivatives. Not quite what we were looking for!

Luckily the Unity Asset store had just what we needed - some nice, slightly cartoon-y looking orc characters, ready-rigged, with a few sample animations included.


These orcs not only keep their humanoid shape, but also manage to capture the ork-iness of an orc: the long, muscular arms and slightly hunched stance tell you that these are definitely not just human characters that have been coloured green.

In fact, we're not quite sure how to go about "re-skinning" these fellas, but it can be done. For now we're more interested in getting a usable character or two. These characters also come with a couple of bits of armour, which can be attached to empty game objects, placed on the elbows, shoulders and knee joints.


What we needed was a bit of 3DS Max magic, to create some custom armour that we can then simply hook onto these connection points on the model. Here's a run down of how we created our first ever 3DS Max model, from scratch.

Firstly, we're creating a "blood-bowl-like" shoulder pad, complete with raised edges and lots of spikes. This is like a squashed-up half-orange shape, with a bit of modification. This is how we did it:

The first thing was to create a sphere, and rotate it so that the "segments" travelled around the object, from top to bottom. Then we reduced the number of segments as low as we could go without it looking too angular.


We only actually want half a ball, so we changed the "hemisphere" option to 0.5.
Setting "slice" to 180 meant that as well as only drawing half the ball vertically, this half-ball shape was cut horizontally, so only 180 (of the total 360) degrees of the shape were drawn


We then made two copies of this quarter-ball shape, and placed one each to the left and to the right of the original. We made one slightly larger than the original and placed it - slightly higher and slightly to the right - of the original.


With the first shape selected, we created a new compound shape object and selected "pro-boolean". This allows shapes to be added together, subtracted from each other and combinations of these functions. Ensuring our first shape was selected first, we went for subtraction and started picking.


When we selected the (larger) shape that was overlapping the original, it immediately took a big slice out of the original shape.


We then took the other shape (previously deposited to the left of the original) and scaled it down slightly, before positioning it in the "empty space" just created. Then created a clone of this (smaller) shape and put it to one side.


Already it's starting to look a bit like a shoulder pad from a Games Workshop character (although at this stage it's more sci-fi Space Marine than fantasy Blood Bowl player) To make 3DS Max treat this as one continuous shape, we once again created a compound shape - only this time selecting unison as the pro-boolean modifier, and selected both pieces.


We're starting to get there - only we've a big solid lump of a shape, rather than a nice, hollow shoulder pad. So after shrinking the new quarter-ball shape (that we set aside earlier) just a smidgen, we placed it slightly offset from the shoulder pad shape:


Another compound shape/pro-boolean substraction, and our shoulder pad is really starting to look like a "proper" 3d model.


All that remained now was to scale the shell to make it slightly less wide (while retaining the height) using the scale cursor selector from the top toolbar....


... and add some cones-for-spikes:


A few extra shapes were thrown down (cylinder slices under the spikes, additional compound shapes on the corners of the shoulder pads) and we're pretty much done!


Skinning - or UV-mapping - 3d models is an art within itself. We managed to create a half-decent layout, ready to create a bitmap to apply to our model. But this is going to need some serious planning to get a half decent result. But so far, we're pretty pleased with making a 3d shape that not only looks ok, but exports as FBX and imports perfectly into the Unity game engine.

Maybe it won't be too long 'til we have a team full of Orcs ready to play Digital Blood Bowl after all.....

Tuesday, 26 May 2015

Karaoke + Jamming = Jamaoke

The other night we hosted another of our blues jam nights, this time at the Neptune Inn in Hove.
The Neptune has a reputation locally for being something of a music bar (it's not really big enough to call a pub, but is a great little venue - and gets quite packed in there when a good band are playing!). So we really wanted to make a half-decent impression with our first (hopefully of many) jam night there.

Now jam nights can go one of two ways.
The first is a house band play some songs, and people are invited to get up on stage and join in. These can be great nights out, but do tend to become a little bit "clique-y" after time. The same faces turn up and play the same songs - or the band have preferred players who they try to encourage to stay on stage.

The other kind of jam night is a bit more "messy" and more of a "jam" than a "play-what-you've-been-practicing-all-week" kind of session. Whoever turns up plays along with whoever else happens to be there. Normally this means people stick to "simpler" tunes, or at least common 12-bar patterns, or chord structures that are quite predictable, so everyone can easily play along.

At our jam night we wanted to avoid the clique-y-ness of a "structured" jam night. Plus, we didn't really have a house band - we had no idea how many people, let alone who, would turn up!

But we didn't want our jam night to be too messy either, nor did we want to be confined to playing three-chord, 12-bar blues all night. What we needed was something like a teleprompter, much like you see at karaoke nights.

So anyone with a passing familiarity with a song can join in - as both the words and the music are displayed on a large screen. And that's exactly what we did.




A few nights before the jam night, people intending on playing were asked to fill in a website, with the chord structure (and lyrics) to songs they wanted to play. We also added in some songs, so that we had some "filler" numbers for on the night.

Using nothing more than a bit of simple javascript, we built an on-screen highlighter, which could be moved along using the arrow keys on the keyboard. Left and right moved the highlight one place to the left or right, and up and down moved to the start of the next/previous section (verse or chorus, however the song had been entered onto the site).


It worked surprisingly well.
In such a tiny place as the Neptune, the massive screen did look a little imposing. But the basic idea worked quite nicely. We even managed a half-decent version of Peter Green's "Need your love so bad" played by a hastily-assembled band - many of whom had never even met before that night - playing a song that many had never played before - simply following along to the chords as they flashed up on the screen.

The actual jamaoke system basically consists of a TV with HDMI input and a Raspberry Pi containing a clone of the website used to upload the songs (the Pi is running MySQL and an Apache web server to host PHP web pages).

In the fullness of time we'd like to make the system operable by the band on stage - perhaps using foot pedals or similar to move the prompt along. Or maybe even hook it up to a MIDI-based "clicker track" so that the highlighter moves automatically over time. Such an approach might need a slightly better band on stage though, as it could prove quite tricky keeping the (live) music in time to an automated system.

For now, we're happy to just jam along and control the jamaoke system manually. Sure, it needs an extra person - for now - to keep everything in sync. Maybe in years to come our jamaoke operator will be known as our "fifth Beatle"....

Friday, 22 May 2015

Press-n-peel toner transfer - best printers

We've known, almost from the day we got it, that the Brother laser desktop printer isn't as good as the big massive Xerox we used to have, for press-n-peel toner transfer.

When printing onto the blue paper, the images appeared "scaly" and after transferring, large planes appeared pitted. This was made even worse when we tried our cheap chinese press-n-peel alternative - it was practically unusable (our first pcbs did actually etch into working boards, but it would only be a matter of time before we started getting impossible-to-debug hairline cracks in traces).

However, we weren't quite ready to give up on our chinese press-n-peel alternative just yet.
The blue original paper is about £21 for just five sheets. After postage costs, that's nearly a fiver a sheet!

The cheap chinese stuff we got cost us ten pounds for a hundred sheets, delivered to the door. That's 10p a sheet. A hundred sheets of blue press-n-peel would be in the region of £450!

After doing a bit of digging around online, we found a few forums in which readers said that they too had problems with press-n-peel and the Brother desktop laser printers. It's all to do with the propriety toner they say.

Now we already know that Xerox toner works really well. It's something to do with the high plastic content in their toner, apparently. But which other printers are recommended for toner transfer etching?

  • Xerox Phaser printers give great results
  • Oki-based printers are the same as Xerox (one is just a re-badged version of the other!)
  • From experience, we know that HP Laserjets give a decent result
  • A lot of people have had success with Dell lasers.


As it happens, a seller local to Nerd Towers was selling a Dell laser printer (an unwanted office raffle prize) for £20. For less than the cost of replenishing our blue press-n-peel, we could get hold of a different laser printer to try with our chinese clone paper.

Even if the chinese paper still turns out to be no good, we're not really very happy with the Brother desktop laser printer, so it seemed like a twenty-quid punt; even if we had to stick to blue paper in the future, the Dell surely had to give better results than the nasty Brother printer - didn't it?

A few hours later, we had our Brother printer on Freecycle, and a new Dell printer installed.


Already the black print on the cheap chinese paper looked better than the results we were getting with the Brother printer. Things were looking promising....


On the press-n-peel blue, however, the black toner still appeared quite "scaly", just like the Brother. Perhaps not so promising after all!

The yellow image transferred onto the copper pretty well.


It's not 100% perfect, and there are still a few little areas where you can see the image is slightly broken - around large planes - but all the tracks and pads transferred as solid shapes and look good. This transfer looks better than the images we were getting with genuine press-n-peel blue and our Brother printer.

The press-n-peel blue paper gave even better results


Nice solid lines, good definition on the pads, and large planes completely covered in toner. The best transfer we've had since the days of the Xerox printer!

And for the final test - etching.


The cheap chinese paper actually performed pretty well. There's still a bit of pitting around the large planes, but the traces and pads all came our really nicely. There's probably no problem with colouring over the large planar areas with a sharpie pen before etching on the next board.

In comparison terms, we felt that this was actually a better etched result than we got with our Brother printer and the genuine press-n-peel blue paper.

And to complete the test, here's a board etched using press-n-peel blue and the new Dell printer.


An almost perfect etch. Pads and traces and sharply defined, and large planes are complete and full, with very little sign of pitting. There's no doubt that press-n-peel blue gives a superior result. But our cheap chinese alternative paper is actually pretty usable too, when used with the right printer!

So there we have it.
Toner transfer is highly dependent on the type of toner in your printer (and by extension, since most people stick to the toner provided by their printer manufacturer, the make of your printer).

We've never had success with using magazine paper or cheap photo paper, but others swear by it, because it's a much cheaper alternative to press-n-peel blue. Maybe they're just using laser printers that happen to work well with the type of paper that they're using. Because we've just found that not only does the paper make a difference to the transfer, but the type of toner being used has a massive impact on it too.

So it's quite possible that you can use cheaper alternatives to press-n-peel blue toner transfer paper; you just need to make sure you use a suitable printer with it too.

In our experience (from the limited number of different printers we've actually tried) we rate laser printers in the following order, for toner transfer:

  • Xerox/Oki - the best results by a long shot
  • HP Laserjet - very good results requiring little or no touching up before etching
  • Dell - very good results, a little touching up required on large areas
  • Brother - don't even bother; useable only with expensive blue paper and lots of touching up still required before etching

For now, we're pretty happy with our Dell laser printer.
And with a stack of 99 sheets of cheap chinese press-n-peel alternative, it'll be a long time before we hope to repeat this kind of experiment - there's enough paper there to keep us going for a long time!



Tuesday, 12 May 2015

G1Xon multi-effects pedal

Having made a few different guitar pedals in recent weeks, it's been great fun just playing with shaping the sounds that come out of the guitar and into the amp. Playing loud is always great - far better than practicing with headphones or - even less fun if your neighbours object to too much noise - without an amp at all.

The few different effects created recently all sound great in isolation. Hit the Fuzz Face pedal, and a nice, warm fuzzy sound comes out of the amp. So the pedal is doing it's job.

What we haven't yet tried is actually comparing the sound from our home-made pedal to the sound of a genuine Fuzz Face (or Fuzz Factory, for the more complex, germanium-based effect). And there's only really one way to do that, and it involves buying a genuine Fuzz Face/Factory pedal.



But what exactly is "genuine"?
There are a few different Fuzz Face pedals available on the market - some retaining the original "face" design, some looking more like the "boxy" pedal we made ourselves. The biggest problem with a "genuine" Dunlop Fuzz Face is... the price. Nearly a hundred pounds for something which - we know from making one - has a few quid's worth of components inside it, a fancy pedal shape, and a brand name. That's a bit too much, just to cure a passing curiosity!

While in Brighton town centre (ok, pedants, city centre) I wandered into GAK (Guitar, Amps and Keyboards). I thought I might pop in and try out a genuine fuzz face and - while not exactly a side-by-side comparison - I'd at least be able to tell if it sounded vastly different from the one we built ourselves.



One of the really nice things about trying kit out at GAK (other than, of course, a massive shop jammed full of a huge range of guitars) is they ask what guitar you use, which amp, and try to set you up with the same kit. They didn't have my twin Laney Hardcore amp, but I was more than happy to try out one of their Orange amps. But they did let me use a brand new Yamaha Pacifica guitar (my current favourite) to try out different pedals with.

It's the little touches of great customer service like this which reminds us why we don't always get the best deal by "buying blind" online.

As it turns out, our fuzz face sounds fuzzy and buzzy and an original Fuzz Face sounds fuzzy and buzzy too. I can't really say whether or not the two are comparable. Because, while at GAK, I forgot all about Fuzz Face effects, once I came across a really "good value" multi-effects pedal: the G1Xon from Zoom.

This bad boy was on sale at £59 - over 120 different effects, a drum machine, expression pedal and 30-second loop recorder, for less than the price of many of their "boutique" effects pedals. It just seemed rude not to try it out.

Now I'm no great purist for "guitar tone". I play everything at eleven and it's either loud and clean, or crunchy and dirty. There's no mid-ground when I play. But being able to easily flip between a massive range of different effects suddenly had me wanting to play riffs from songs I'd long forgotten about over twenty years ago, and pay a bit more attention to how they actually sounded.

The ability to play a backing rhythm and record (and playback) multiple layers with the 30-second looper clinched the deal for me. With a headphone output, this little unit is not just a bazillion effects in one, it's also a great way to practice leads and solos to your own backing tracks, without having to faff about with amps and recorders (nor even setting up my previously favoured rig of a guitar into Native's Guitar Rig software-based amp/effect simulator on the PC).

If I tried to build even two or three of the simulated effects in this unit, I'd be over sixty quid in no time, after electronics, jack plugs, footswitches, enclosures and so on were all taken into account.

After less than 10 minutes of playing around in the shop, I'd splashed the cash and was on my way back home with the new effects unit all boxed up, ready to try out. To date, I've only used it for a total of about an hour. But what a great hour it's been - mixing effects, playing with compression and overdrive, getting the hang of a wah pedal again, recording and playing along to all kinds of different backing tracks. It's been great fun!

It also transpires (after much online searching for the same model) that GAK are selling this pedal at below internet prices. So not only do you get great customer service and an opportunity to try stuff out before buying, but it turns out they're also cheaper than buying online.



After this weekend, I might just be visiting GAK a little more frequently!

Inductorless wah pedal using TL072 op amp

Having made a few guitar effects pedals lately (a fuzz face, tuner pedal, fuzz factory and so on) and spurred on by the relative success we've had to date, the next obvious project seemed to be a wah pedal.

A wah pedal is a great effect for a guitar. It has an instantly recognisable sound - and can make even the simplest of riffs sound really cool and "bluesy" - perfect for a live jam night, for example.

There are quite a few different designs for wah pedals, but usually break down into two distinct types - inductor based (like the classic Dunlop CryBaby) and non-inductor (or inductorless) varieties, like the ColorSound Wah. We even made a simple wah, a few years back.

While it worked, the wah effect wasn't very pronounced. Not really understanding the concepts behind analogue/audio electronics, it just meant this was something we learned to live with - i.e. we'd made a pretty poor wah pedal. But it was still cool - because it was made, and not bought (though in truth, our genuine, second-hand, Dunlop CryBaby pedal is the one that gets used if we want some of that funky 70s chukka-chukka sound, and the home-made pedal hasn't really been used much after being tested out just to see if it works).

Having recently discovered a load of power amp and op amp IC chips in a stash of stuff long forgotten in one of our many moves, the idea of making an inductorless wah seemed strangely alluring. After all, what better way to use our newly created pedals, than to daisy-chain them and make some really crazy sounds at the next jam night?

Most inductorless designs use the "classic T" layout.
In fact, this is the core schematic for the £159-a-time ColorSound wah pedals.




A while back we had a go at making one of these, but the effect was more of a poor tone controller than a "proper" wah sound. Instead of reducing the frequency "envelope" of the sound, it simply cut either the high-end (treble) or low-end (bass) from the guitar sound.

But a quick google search for "inductorless wah op amp" turned up a few interesting circuits.


.
This design uses a single TL072 dual-channel op amp.
If truth be told, we don't really understand how it works (yes, there are explanations on line about what each part of the circuit is doing, and the idea of creating an envelope and phase-shifting to create a peak of sound in a limited frequency range does make sense - just not in the way that explains why certain components are used, and why specific values are chosen).

But that's not going to stop us having a go at making one anyway!
After all, if it doesn't work, the sum cost of the components is probably little more than  a quid or so (if it doesn't work, we can always reuse the more expensive parts, the like jack sockets and footswitch in another project in the future!)

The nice thing about this design is that the wah control is a single 3-pin potentiometer. And from where it's placed in the circuit, it looks like it should be easy enough to isolate from the rest of the circuit. The reason?

Well, it might be cool to have an onboard, hand-operated, maybe capacitive sensing wah controller, instead of a footswitch. Or perhaps we could create a sequencer to vary the resistance between R2 and R3, to control the wah sound. Or use an ultrasonic sensor to vary a resistive load between the two resistors. Or an LDR... or any number of other ways of creating a variable resistance.

In short, being able to isolate the bit that controls the wah sound means we can use this same design for a number of different types of wah effect, rather than being stuck with the old-fashioned foot rocker switch (though in all probability, that's the most likely design we'll end up using).



(press-n-peel ready layout - the 9-pin footswitch is not necessary - it was just used during the design of the PCB to ensure we got all the connections on the board!)

This PCB layout is surprisingly small, just 30mm x 45mm, so it should fit in even the smallest of enclosures and still leave plenty room for the battery.



Sunday, 3 May 2015

Testing Chinese press-n-peel alternative (again)

With all these guitar pedals we've been making (as well as the PCB fails, wrongly-mirrored SMT designs and just outright failures) in recent weeks, our stock of press-n-peel blue paper has been hit severely.

The last lot we bought online was about £15 for five sheets - nearly three quid a sheet! Today, the cheapest we could find it on eBay was £21 + p&p. That's quite pricey.

Now we've tried alternatives to press-n-peel in the past, and found the old blue paper to give the best results. At least, it did when we used our big £2k-worth of Xerox printer. But that big old beast has gone to BuildBrighton, and the little desktop laser printer we have here at Nerd Towers is a hopeless Brother something-or-other.

Even on blue press-n-peel, the image is flaky, often there are broken traces and touching up with a Sharpie is now a common job. So we thought we'd give some of this cheaper transfer paper a try. The Xerox was great with press-n-peel, and so-so with cheaper, starch-based transfer papers.

But our Brother printer doesn't get the same crisp, sharp lines on blue paper - so perhaps it might actually work better with a different transfer paper? There was only one way to find out...

A quick click around on eBay and five days later, we had an impressive 100 sheets of transfer paper delivered for less than a tenner. That's less than 10p a sheet, compared to over £4 for press-n-peel blue. While that does sound cheap, it could still end up being quite pricey, if it doesn't work!

So what do the results look like?

Here's a "control". We're using the same method for creating these two boards, preparing the copper the same way we usually do, for both transfers, so that the only thing different should be the transfer paper. First up, our regular press-n-peel blue paper:


Straight out of the printer, the image is sharp and clear. Well defined tracks look like we should get a good image. But if you shine the paper towards the light, you can see that the toner has not been laid down as a continuous line of "ink" but appears to be "scaly" and looks like it could get put down in "layers" on the copper board.


The transfer has gone on ok. There are a couple of spots of black toner still left behind on the transfer paper, but most of the mottling is happening on the ground planes, and larger areas where it has been filled in. There are a couple of traces that were cracked, and a few with noticeable gaps in them that need touching up with a Sharpie.

Here's the etched board. Despite the slight raggedy edges where we've had to touch a few traces up with a Sharpie pen, it's not bad at all. There are a few marks in the larger planes, but the 0.3mm traces have all turned out quite well and the overall look of the board is one where the masked copper has remained pretty much intact.


Now with the cheap chinese alternative:


Out of the printer, the image already shows areas that could be affected by pitting - there are gaps in the larger areas and a few traces are already broken.


Compared to the press-n-peel image, there's none of the "scaly-ness" of the blue image - but you can already see that the quality of the yellow printing image isn't as good as the press-n-peel version.


The transfer process was very impressive. A few passes through the laminator, then about a minute in a cold water bath (just as we've been doing with blue press-n-peel for a while) and the entire image is transferred with no trouble at all. Not a grain of toner is left behind on the backing paper. The actual image transfer is far better than press-n-peel - it's just a shame that the printed image isn't as good to begin with!


After etching, the copper board does look a bit of a mess. You can see that the tracks are not particularly well-defined, but they are useable. Large planes appear "pitted" where the toner didn't transfer as a single solid block of colour, and appeared to have large "pin-holes" in the final layer.

After running a multi-meter/continuity test on all the tracks, they appear to at least work. But the overall finish of the board is a much poorer quality than the press-n-peel board.

So there you have it.
Cheap chinese toner transfer paper isn't as good as press-n-peel (at least, not using our scabby not-very-good-for-toner-transfer-Brother-laser-printer). It all goes to back up Steve's insistence that "you get what you pay for".

But at 10p a sheet compared to over £4 a sheet, and both give functional, working results, it's hard not to ignore the price difference. If only we could find a laser printer that would give a decent printed image on the yellow transfer paper, and things might be different!



Saturday, 2 May 2015

Stompbox guitar tuner stolen idea

If you've ever seen a live band at the local pub (or bar) there's one song you've probably heard more than any other. It's an instrumental, and it goes "dum, dum, dum..... der, der, der...... der, der, ding, ding, ding, ding, ding".

Of course, it's the tune-up song, that just about every guitarist plays when they get up on stage. If you're lucky, you get to hear it once, at the start of the gig. If you're unlucky, they play it three or four songs in (and you've just endured the most atrocious fifteen minutes of out-of-tune string-twanging).

It's a pretty short song (if released as a 7" single, it'd probably have a run time of 0:21 or something) but it's tedious and noisy for everyone who has the misfortune to listen to it.

In a live environment, unplugging guitars from amps set to "moderately loud" can mean lots of popping, crackling and buzzing, as cables are removed, left lying around and generally abused. As a general rule of thumb, once you're plugged in and audible, it's best to try to stay plugged in (and use the guitar body volume to reduce any unwanted noise between songs).

Which means that plug-in tuners have lost out in the fashion stakes, for the cheap, vibration detecting, sit-on-the-headstock-and-detect-the-note-frequency type tuners - especially in a live environment. Which means, that as you tune your guitar, and watch the display at the end of the head, waiting for the note to appear in tune in the little window, everyone else has to listen to "twang, twang, twang" at performance volume; often as many as six times (each string needs to be plucked at least once, even if it's in tune, just to see that it is!)

A little while back, Tom - (the dude in all the videos from the previous stompbox workshop at BuildBrighton) - had an ingeniously simple idea. He took a cheap, plug-in tuner and turned it into a stompbox.

The point? Well, with the footswitch in the "default" position, it acts as a true bypass - simply sending the incoming signal to the output jack (and on to the amp). But when activated, not only can you direct the input signal to the onboard tuner input - you can also short the "output" signal to ground - ensuring that your audience hears nothing, while you're busy playing the open-string-tune-up song.

A plug-in guitar tuner costs about £3 on eBay, so it's no big expense, even it is goes wrong! We weren't not sure if our (cheap Chinese) guitar tuner was exactly the same as the one Tom had, so we had a quick look inside


This particular model had a mic (so it could pick up sound from an acoustic guitar, and be used for tuning non-electric instruments too) a battery compartment, an input jack and a circuit board.


Tom's design was so simple, we just had to rip it off - use it for our own project. He basically just clipped the heads off the LEDs on the circuit board, connected a couple of wires, and attached them to some LEDs that were mounted into the stompbox enclosure.


We ditched the microphone - we'll be taking the signal from the guitar out and it'll probably be a bit noisy for the tiny little mic to be reliable anyway. To make things easier, we soldered wires onto each of our LEDs before arranging them inside the stompbox enclosure. Then the hotglue gun came out and sneezed all over the place, inside the box.


It may look horrible inside, but once the box is done, it'll only need to be opened up once every now and again, to change the 2xAAA batteries that power the circuit board. By running the power lead from the batteries through one set of contacts on the footswitch, the batteries will be physically disconnected from the entire circuit when not in use.


A combination of poor drilling and sloppy application of hot glue means a couple of the LEDs don't sit perfectly true, but they're good enough for the effect we're after!


There's a tangled mess of wires by the time each of the nine LEDs has two (overly long) wires running to them, plus all the wiring between the circuit board and the push button. But eventually we crammed everything inside the little box.


(Before committing to screwing the base on the underside, we tested the pedal. Here you can see we're playing the G string - fnar, fnar - and our pedal is telling us that we're perfectly in tune)

The final pedal, ready for a nice sticker labelling the LEDs.
In our design, the top LED is always on, while the pedal is active (yes, we forget that since the top and bottom strings are both E we only actually needed five, not six, LEDs for the different strings, so found a purpose for this "extra" LED). Because power from the battery is also routed through the pedal, when it is off, the battery is physically disconnected from the rest of the circuit (rather than using the rather leaky soft-on button) so this should help reduce battery drain when the pedal is not in use. So, when the tuner is activated, we'll make this top LED light up (so you can see at a glance whether your guitar output is going to the amp or not).


The final pedal, with all the guts stuffed away inside.

Like our earlier fuzz face stompbox, this was a nice, easy, no-more-than-a-couple-of-hours project, but we've actually got something quite useful from it.

There's no real need for a full write-up and circuit diagram - it was more of a "hack" than a "build". All we've really done is just take existing LEDs, soldered on some wires, and connected up alternative LEDs on the face of the box. For anyone interested, here's how we wired up the footswitch.



The layout for drilling the stompbox enclosure is below.
(the drawing also includes the drilling layout for the earlier, as-yet-incomplete Fuzz Factory pedal, and some ideas for a sequencer wah pedal we're playing about with)