synth-diy

Synth DIY has moved... A reminder

2009-11-22T21:57:00.000Z

Dear all,

The Synth-diy blog has moved to http://www.synthfrog.com. Please update your
bookmarks and subscribe to the new feed: http://www.synthfrog.com/feed

This feed will not be updated anymore!

See you there!!

Aris

teezer!

2009-11-17T09:09:00.000Z

http://www.synthfrog.com/

Tigrics lab!

2009-11-14T05:40:00.002Z

http://www.synthfrog.com/general/2009/tigrics-lab-as-promised/

Mr. Braska returns home

2009-11-11T21:49:00.000Z

On Mr. Braska's new home!!

MOVING!

2009-11-11T07:27:00.000Z

Hi all..

The frog is moving. He goes to his house which is http://www.synthfrog.com

Please update your bookmarks and subscribe to the feed you will find there.

Of course you should unsubscribe from this feed as it will get no more updates.

Thank you all for loving the frog!!!

See you there!!

Parallel project

2009-11-07T20:08:00.002Z

A parallel project starts.. Components are on their way, panel is designed, boards are here.....
it will be an MFOS Sequencer!!!!

For more info, you can look here at Ray Wilson's MusicFromOuterSpace (and he will host Mr. Braska on his US tour!)

Some more views of tigrics' workplace!!!

2009-11-06T09:39:00.002Z

Some more views of tigrics' workplace!!!

A corroded Ultimate Percussion module. It is also here (exactly the same :) This one must be quite rare. Couldn't find any manufacturer info..

Well here we are at a cable junction.. A serge VCs is right behind Mr. Brask and LFO/VCA at the left.
The mising link might me a filter? The red in the middle?

Another view.

Here, Mr. Braska with cucc... The drawings of tigers all over the place is by tigrics' hand

Beside the distortion generator... BZZGGFFFZZZZWEEEEZZZZFFGGHHHH

VCO Core. If it has hard sync it will be VCO Hard core!

Module graveyard!

A small VCF

The unfinisheds

Future formant

MS20 VCF!! This should include a sample!

Mr. Braska with the owners of all these modules: szarvas and MJ. Tigrics pays them rent to use them!

And of course, Mr. Braska is always in the mix. Or better, in front of it!

Moving domain.

2009-11-05T07:15:00.001Z

Hi all!..

I am in the process of moving out of the blogspot.com domain. I got the synthfrog.com domain with php/mysql hosting.

I already tried wordpress and it seems quite capable to support a blog and some pages that should be permanent. (this was one of my main reasons to have my own code to handle).

I would like to ask what platform you find better for a .com, self hosted blog.

Could you please help me? If I don't come up with a solution, Mr. Braska won't be giving me Christmas bonus this year!

Thanks.

Aris

Mr. Braska's secretary.

PS. www.synthfrog.com is active but it is still in copy-this-blog mode.

Update from Mr. Braska's trip in tigrics, Hungary

2009-11-04T21:38:00.000Z

Mr. Braska felt right at home at tigrics'. There was a moose named SzarVas to welcome him, show him around and let him use his gear.

Here you see both of them on the STEP64!

After that, Mr. Braska took a quick nap on the midiman!

And afterwards, refreshed, he set out to explore tigrics' self made modules !

And there is a Shaper!!

Small break!

In front of pocket history poster

And back to the house, lying as sexily as a frog only can, on a wasp filter and a ring modulator!
Great sonic potential!

This is tigrics' backlog!

Well, tigrics mentions his workplace is, like, everything, everywhere:

"there's not much of a workshop here, it's all over the room.
2 soldering irons, two drills, still no stand,
I acid next to the entrance, doors open,
have a computer on the desk with a good wacom, no mouse, oh no,
I draw a lot... I like inkscape, but flash even more.
still use pencil a lot.
quite a few partboxes, and bags with stuff sorted, resistors in cd wallets"

Well, just drop over his site and see for yourself.
He is as talented with pen and paper as with soldering iron/pcb :)

He promised some photos of his lab tomorrow!!!

Mr .Braska arrived at tigrics

2009-10-30T08:37:00.000Z

Yesterday morning, Mr. Braska arrived at tigrics (http://www.tigrics.hu).
He was tired from the trip and fell asleep on a G2.

Mr. Braska will spend the weekend there, photoshooting with various synths.
He has found some same-sized friends there as you can see from the following pic..

More updates from Mr. Braska during the weekend.

And off we go!

2009-10-27T22:04:00.001Z

Well, the tour of Vinnui's home and lab has finished.. Mr. Braska will attend a
salsa party from what I hear and then will take off to another destination,
still in Hungary!

Outside vinnui's house is like a small forest, and Mr. Braska felt right at home

Our hosts, Balazs (vinnui) and Kende (his son) were very loving and took
good care of the little frog. Kende was so sweet and he made Mr. Braska
remember his former occupation, being a toy, before becoming a synth model.

Now the little frog has to travel again. So, until further notice, bye bye
from Mr. Braska. He will send us photos when he arrives at the next stop!

Braska on 1RU effects

2009-10-26T22:04:00.000Z

The following pictures show Mr. Braska on the 1RU effects
that vinnui will use with the modular.

These are:

Behringer Virtualizer Pro - digital multieffect
MAM RS3 Resonator - analog resonator (3 bandpass filters + LFOs)
MAM Warp9 - analog filter, based on Wasp filter, with midi, etc.

In the guts of the polysix

2009-10-23T21:09:00.000+01:00

Another photo-shoot, now with a well-respected, retro, gutted synth,
the KORG polysix

Vinnui stated that this polysix had a faulty PSU so after the modular is
completed, he will fix it.

Lucky frog, now sits on top of the polysix and he has nothing cut-off ;)

There is the position of the non-existend PSU

But everything else seems in order.

This is the PSU of the modular

And it seems to supply enough power to support Mr. Braska too!

And a cameo appearance of a midi keyboard!

Mr. Braska chez Vinnui's

2009-10-21T19:24:00.001+01:00

It is a fact!! Mr. Braska is now at Vinnui's home! The first photos show him posing for various modules vinnui has made!

(and on his mini-mac)

This is a part of his lab. Mr. Braska feels good being around electronic components

The frog and the tool!.. Mr. Braska and the soldering iron

Mr Braska samples the boards. He will hold them later

Vinnui's ADSR .. Mr. Braska likes the neat cable work!

Ridin' the noise train!

In front of Vinnui's awsome panels!!

Mr Braska asked about the spined skull design. It is hand-drawn by Vinnui himself
and vectorized in Inkscape

Attack of the VCOs

Mr. Braska will now rest for a while in his favorite place. The module box!!!!

This is it for today.. But tomorrow there will be much more!!

Goodnight Mr. Braska

SubAtomicGlue's SID

2009-10-18T09:26:00.000+01:00

While searching for midibox SID stuff I stumbled upon Subatomicglue's super-extensive build log. He has info on almost every aspect of making a SID synth. It follows the panel design of the original Midibox SID made by T.Klose and it is packaged inside a Commodore 64.

He has used a custom made panel (Made by Schaeffer)

and he is quite good with the soldering gun :)

More of it on his work log

Frogs on the move

2009-10-16T10:38:00.020+01:00

Braska will be away for some time. He wants to know more DIYers and I will grant his wish by letting him do just that!!

From now on, Braska will be on the move. DIYers will get to host him and shoot him (photo shoot that is) with their lab and equipment.. He won't say no to have his picture taken on top of an exotic synth/musical instrument either.

.. So, if you want to host him, just drop me a comment/email at akorbeti [at] gmail [dot] com.

Now, on to his first trip!!!!!!!!!!!!!

(the following photo is on the weigh scale of the post office. There, he had to play dead. Stuffed frogs don't speak or move. (something like toy story!))

Today is Blog Action Day!

2009-10-15T21:51:00.000+01:00

Click the image to visit the site.

Braska online!

2009-10-13T23:17:00.003+01:00

Braska is now online!

You can follow him on twitter where his rantings will be posted! (and the occasional photo too) and on facebook (if you don't have trouble being friend with a frog. Well he might be a prince but I wouldn't count on that!)

His addresses:

http://twitter.com/braskathefrog

http://www.facebook.com/synthfrog

Join us!

Caniballizing the laughtop

2009-10-13T20:35:00.003+01:00

What follows is the destruction of the laughtop. This is not for the faint of heart!

Braska is here still, helping with the hard stuff (posing and getting in the way). When I tell him "get the screwdriver" he always appears with a cocktail in his froggy hand, sipping.

There is a small, lo-fi speaker which I just might keep!

The "mouse":

This will host a rotary encoder when finished:

Closeup of the lo-fi speaker

Name of frog spelled in Greek: (missing the last α) "ΜΠΡΑΣΚ(Α)"

Lower part done.. now to the screen disassembly

This spring is what keeps the screen in position

Braska sits on laughtop's screen and brain.

Screen, off

We like "windows"

Well, this is nice!!

Now, some cutting of plastic parts (specifically, the battery compartment) must take place.. I will have to replace the heat sinks also on the sid because they are BIIIIIIIGGGGG..

SID Repackaging

2009-10-09T10:28:00.001+01:00

Remember the babyBotte ? It started it's life as a simple shoebox and then got upgraded to a package that is sturdy and useable with a jack for external PSU so I wouldn't have to rely on batteries.

Same story about the Music from outer space WSG that got a serious upgrade and became a module

Not to mention the AVR-Synth that was repackaged, twice

Well today, another project is starting.. Packaging the Midibox SID to an item I had to wait long to get my hands on!

Being a parent has the advantage of being around toys all the time. The one here is the perfect packaging for my SID synth :Fisher-Price Laughtop . So i got the kids another saying that this was broken and started with Braska to ponder on how to put the SID in.

This is it. with Braska on top..

Since the SID needs at least one rotary encoder, we were thinking of putting it where the laptop mouse now lies. I would make a nice flat round, orange painted knob to put so it doesn't stand out a lot.

At the back there is an abundance of space. Considering that we will have to accommodate two MIDI sockets, two audio jacks (1/4") and the power jack, it should be just enough..

Inside, there are lots of keys (Greek version laptop has 24 keys plus a bigger green enter-like button). The minimum amount of keys to be used is 6. I could wire the others to different functions of the SID. Eg you could have one key, bring up the resonance/cutoff control so with the encoder you could have realtime fun with it.

As you see, the 20x4 White-on-blue screen is EXACTLY the size of the laptop opening. This would look great when finished!!

The next step is to gut the laptop. This will probably be done this weekend because from Monday morning, Braska will be on a (rather big) trip. More on this later on.

Stay attuned!!!

Me be back!!

2009-10-07T10:38:00.002+01:00

Hi all,

for starters, let me beg for forgiveness for being away for such a long time!

My plans were interrupted a bit from being a parent for the second time. Now with two kids messing with Braska, I can't find him anywhere. And when I do, he is all wet from being gummed to death. The available time for hobbying has shrunk but this does not mean that I cannot delve into various DIY projects.

So, I hope that you will be with me for this.

PS. Due to the lack of search time available, if you would like to share your DIY Synth project with the rest of the readers of the blog, please do leave me a comment or email with your page/blog.. I will be more than happy to post it here too and have a link to your pages!

Thank you all,

Aris

Midi2CV Part 1

2009-04-29T19:09:00.002+01:00

This is a module for my synth. A pretty basic module as it is a note to Control voltage converter. It is based on midibox ucapps.de designs and it features 4 CV and 4 gate outputs. These can be made 8 bits which are quite good for note playing (4 x 8 bits) or can be made 4 and 12 bits each pair. I chose to have them all at 8 bits resolution.. The circuit is ready and it needs a panel (which you see in the photos) and some wiring an mounting

I used a long screw I found in the hardware store. It was a one meter , 3mm width screw which I cut at around 17 cm pieces. Then glued a nut on the panel with instant glue and put resin glue on top of it. Put the screw so now the nuts are filled with resin glue.

You can see here the resin . To align the screws, I fixed the other sides of the screws on a board .

WSG got a new dress

2009-04-11T20:51:00.002+01:00

Made the panel for the WSG (Weird sound generator).

This is it. It is made like the one I've done for the SoundLab beside it. I scanned the panel with the holes, overlayed the picture I've made (actually it is just boxes and text) , printed it on glossy paper and then sprayed it with a matte varnish to give it that "professional" anodized look. If you look carefully though, it is still paper on sheet metal.

Naturecordings

2009-04-11T20:47:00.002+01:00

I just started a new blog with nature recordings. It is spring now and it is very easy to run around recording interesting things. So please do visit http://naturecordings.blogspot.com/, tell me what you think and what would you like me to put (if I can that is)

Soundlab and WSG sonata

2009-04-03T22:37:00.002+01:00

The WSG (Weird sound generator) took it's place beside Soundlab. So there are two samples, one (http://rapidshare.com/files/217106360/hhh2.mp3) which uses both of them and one
(http://rapidshare.com/files/214296536/hhh.mp3) that uses only Soundlab..
There is a little effect processing afterwards (delay+ phaser).

Both are fed from a +-15V PSU without any problems whatsoever.

An interesting experiment is to plug the output of WSG to the CV input of the SoundLab. It doesn't cover the entire 0-10v range as an output but with a mixer/amplifier before the insertion you could have dramatic results. Nevertheless, it still sounds quite interesting..

Making a module case

2009-03-30T21:17:00.004+01:00

It is about time me and Braska started making a case for modules/synths we've made. The panels for the modules I've made are 12x12cm a unit and I have some standard panels made with 16 holes evenly spaced. These are the generique type that may house vcos, filters etc.

The big one is for midibox seq. which slowly but surely manifests on my desk. The others are for the soundlab I've finished and for an AVRsynth I've repackaged so this is a no-go.

So, the construction started by drilling holes for wooden dowels

... and marking the other wood panel where they should land

.. thus constructing the raw cabinet sized aprox. 72x36cm

The hard edges on the front side where smoothed with a router

.. and then it was painted with four coats of satin walnut finish (Water based, doesn't stink, washes easily until it gets dry. Quite nice actually)

.. the balcony was a mess (and still is because I started something else :)

.. and here is after first coat

... and this is its current state, with soundlab fitted

The WSG is the next thing that will be fitted along with a yusynth filter and a midibox Midi2CV

(you can see that it is getting warm here on the white thermometer on the right!!)

Tempcos in the missed

2009-03-30T21:08:00.005+01:00

The yusynth VCO was missing a tempco. So I ordered some from Vintage Planet and as soon as I got them (ultra fast) I put them on both the VCOs I've made and TADAAAAA! ONE OF THEM WORKED almost as expected (the other one is still too unstable). So I will hunt down and kill the wrong component. (I hope)..

(Thank god I had the oscilloscope.. the first frequency I could read was 43 KHz!!!!)

A working SID Synth

2009-03-30T21:00:00.002+01:00

The SID synth is working!

As I just bought a simple oscilloscope, wave shots follow..

The SID filter works by using two capacitors. I think it works by switching them on and off in sequence. However it works internally, you can experiment with the values of the capacitors. So to experiment without solder/desolder I put a pin header.

So:

The saw

The triangle

The pulse

The noise

The filtered saw with lots of resonance

Now on to a casing.. I had some ideas. But I would like first to get my hands on something to realize it.. Patience is a virtue. I am no virtual, I am real (I think :)

The Nibbler and Collin the fortune teller

2009-03-17T19:50:00.003Z

Some time ago, Collin saw a nibbler in my future and the prophecy has now been fulfiled!

I GOT A NIBBLER!!! HURAAAAHHH!!!!

Of course, the first person(?) to grab and test it how comfortable it is to sit on, was Braska:

The nibbler works like this: it passes the metal "jaw" you see in the pictures below through the metal while keeping it in place. This way there is no distortion on the metal like when cutting it with scissors made for metal.

The jaw has a jagged edge or else it would be impossible to get a grasp on the sheet. It would slide off. So while cutting, it actually works like two pairs of scissors. It removes the middle section. This produces a curly string of material like the one you get when you slide the knife on butter.

To cut efficiently and without any distortion/bending, the upper "jaw" of the nibbler must be in full contact with the material . Otherwise, it would pull the metal up and bend it.

The material used here was aluminum, 2mm thick. It was VERY easy to cut it. It was like cutting a thick cardboard with a pair of scissors. It is extremely accurate too! if you have a guide, you can't go wrong

Other tests included of cource PCBs that were cut like butter! It doesn't leave a jaggy edge!

Cutting a .8mm thick aluminum sheet, was like cutting through paper. I found in the local hardware store a 1000x120x1.5mm aluminum sheet which I am going to get TOMORROW!!!

The hardest of all was a 1mm steel sheet. Now THAT was difficult. Thank god I wont have to work with this stuff after I get that aluminum sheet.

Now I can fit all my LCDs behind well (well, better) made panels. There is another thing I have to figure out. The smallest possible diameter that a hole must have so as to insert the jaw completely to start a cut from the inside of the panel.

From what I have tried up to now, it must be just a little more than 9mm in length.

Sowing the SIDs of love

2009-03-13T07:53:00.004Z

All things come to those who wait. But even if you wait for an eternity, no SID will come your way unless you hunt it down because it has been long since it was discontinued! And so I did hunt it!!. Two found and thus, the quest for the MidiBox SID began.

It is a stereo SID synth. Two sids, one for each channel. Made the Core (the old 8 bit), got two 18f4685 (of which I toasted one because I gave it 12 volts!! :( Thank god I got two) made the boards and TADAAA!!!!

The SID works!! If you play something via midi you get a square lead sound.. nothing special but it is there.. So now I must add buttons and encoders.

The only thing that went wrong apart from the burnt PIC was that the 20x4 blue/white screen I had to put , went cookoo!! Maybe this was a result of the 12 volt jolt! But, no real harm done since I have a spare 40x2 screen.!!

Now I REALLY have to finish the midibox router and midibox sequencer.. I have no excuse, neither does Braska!!

Inter-hobby relationships

2009-03-11T09:04:00.001Z

This is my friend, Bella. She is a small hippo, brought to our house via toyvoyagers (www.toyvoyagers.com)
This is (one of) our mom's hobby (Aris' wife, mother of their children and host of me, Braska)
I would like to travel a bit too but there is a lot of work here and Aris would be lost without me in his pictures!!

Braska

Midibox Day

2009-03-11T09:00:00.001Z

This is the day of the midibox. I started making 4 MidiIIC modules and 4 Core Modules (pic based)
The four MidiIIC will be used for a midi router (again, a midibox project) I am making.
One of the cores will be used for it too. The other one will be used for a SID engine (with TWO sids!! Stereo!)
(I already found the SIDS). The other two core modules will be used for various experiments and to continue
the (delayed) development of the harmonic table project. Of course Braska is here to help!!!!

Soundlab revisited

2009-03-04T21:58:00.002Z

The sound lab is a well known project for beginner-intermediate DIYers. Of course Braska wanted some publicity shots.

Here, we are at the process of connecting the panel.

How I got this panel is a different story that will be posted on another artice.. Well, the hard thing about the soundlab was that, the first time I turned it on, it didn't work at all (surprise, surprise!!). I followed the signal with my soundcard/oscilloscope (crappy method but ....) and found that there were two faulty transistors. I replaced them and TADAAA!! It worked. Not as expected but there was sound comming out of the output. After a lot of debugging and cable tracing, all faults were solved and the SoundLab was playing well. There was the time that I should make it pretty.

To add to the difficulty, I decided on a mod. I would put a frequency modulation knob that modulates oscillator 2 with the frequency of oscillator 1. The mod is very well described at the musicfromouterspace.com (the link takes you directly to the mod).

At the beginning, I was thinking of spraying the panel and then add decals on it but after looking at the decal test results I did, I was dissapointed. So the old trusted method of the photographic paper (like I did on the babybote) was the way to go. With one crucial addition. After letting the photo paper dry, I sprayed it with a clear acrylic laquer. This gave it a more "professional" look ( kitch might be the right word).

So the result was this:

The following pic shows the FM addition.. There is some deviation from the initial plan because it was a last minute decision to add it but the panel was already made

I made a simple CV tester with just a potentiometer and a battery and braska seems to get the hang of it.

This was the result!

It wasn't the micas

2009-02-06T22:27:00.002Z

The silver mica 220pF capacitors arrived, substituted and failed... Still no response. Only random noise (if it wasn't random. it wouldn't be noise, would it?). So the only thing that remains to be done is to follow the schematic and have the soundcard probing various positions on the circuit so I can see (hear) where the signal ends.

Ray Wilson from musicfromouterspace.com has a nice article on using your sound card as an oscilloscope and I use http://zeitnitz.de/Christian/Scope/Scope_en.html for display

(Ray Wilson's article is here)

Not quite functional!

2009-01-27T22:22:00.001Z

Made two yusynth VCOs the other day.. None works... But the real problem is that at the schematics it mentions using a 1% silver mica capacitor. I have used plain ceramic and multilayer. Voltages are OK. The comparator and OP Amps get nice voltages. No electrolytic capacitors are the other way around. So it has to be this. While I wait for the silver micas, I might put together a yusynth moog filter clone.

AVR Synth RE-re-packaged

2009-01-19T21:54:00.004Z

Went today to the electronics shop to get some cheap stuff for the yusynth and saw this box for 6 euros. From what you can see, I got it. It is relatively small with a panel area of 15x9cm.

So I went on to repackage my avrSynth16 I had build sometime ago.

There was a failed attempt to house the synth inside a FIRA drawer from IKEA but the design had some flaws (And it was way to big to have it around).

The first step was to make a 15x9cm layout in inkscape and make objects that were the size of the underside of the components I would use. So I could layout the knobs and switches knowing that they'll fit. Purple were the knobs, cyan were the switches.

I made the holes with my newly aquired tools that I mentioned in earlier posts (the step drill that is) and had the panel ready for sticking the graphics.

Since the step drill went up to 12mm diameter, the midi socket hole that needed 15mm diameter, got a little help from my old (t)rusty reamer. (I always had that tool! It belonged to my father from what I vaguely remember)

The simple design is always the best. Made in inkscape. (Super drawing program, open source!)

The time of the knob transplant was stressful. A few wires came loose. (The design is not so clean from what you can see)

So it was obvious that it would end like this.. A big spaghetti bundle.

The hardest job was to fit the boards inside the box. It took a lot of careful squeezing and pulling/pushing wires inside the box. This was done while the synth was playing from a sequencer. It kinda reminded me of some brain surgeries you see on TV where the patient is placed on the bed with an open head, and the doctors have electrodes touching his brains to see what is the problem. When the synth stopped responding I stopped pushing!!

You can see that the panel has a slight bulge at the center..

And now the publicity shots!

Yusynth modular

2009-01-12T21:04:00.004Z

New parallel project starts: The yusynth modular.

this is based on this which is a rather easy DIY set of modules.

The boards are etched, some even drilled, the panels are made (that means that someone else will make them for me, I just drawed (eg designed) them) and the components have arrived (very cheap postage fees to where I live and all components required for this project available..).

Will get some photos of the panels once made.

For now, there is always Braska, lurking in the shadows of DIY.

Basic modules are made: 2 VCOs, 2 LFOs, an ADSR, a VCA, 2 Filters for starters (and the psu that has already been made)

Now I will have to make a case for it.. :(

Making panel holes

2009-01-08T22:20:00.004Z

Making holes for panel pots and switches has always been a major pain in the butt for me.
I tried lots of times to make different sized holes with standard metal drills on tin sheets but the holes always came out at the wrong places or, due to the fact that I don't have a drill stand, triangle shaped because of my inability to keep the panels from sliding up and down the drill. They also came out with lots of scrap attached to them (I cannot find the right word but I mean the metal goo that remains at the opposite side of the drill entrance).

Today, I received in the mail a... STEP DRILL!

Didn't know it's existence till recently but using it has been a revelation!!!

Also I got three tools to make the holes tapered (the smaller two are pictured).

If you are careful with the step drill you get instant holes at the desired diameter (the numbers on the drill are mm). And since there is a taper leading to the next, larger diameter on the drill, you get instant metal-goo cleaning and flattening. No more scrap at the holes...

The following is a 5mm hole. No other tools used!

Below is a 5mm hole but treated with the taper tool afterwards. You can house nicely a 3 or 4mm screw with tapered head.

And the big one.. 10mm for audio jacks and some cheap pots. Instant gratification.

Same rules apply though. If you want to be as exact as possible, first start with a small drill (eg 2mm) to mark the center so as the step drill has somewhere to land.

I would really like to know how other people make their panels and especialy the square shaped holes. This has always been a mystery to me :)

Cheers!

Fixing the MC-909 rotary encoder

2009-01-05T22:40:00.004Z

And of course taking a peek at its guts to shoot some porn in the process:

This is the MC-909.. It is my favourite synth because it allows a hands-on approach to sound synthesis. Even if it is targetet to the DJ market (which I am not!), it is capable of very interesting textures (and it has a nice sampler even if it lacks the velocity and key multilayering of the high-end samplers)

I got it second hand from ebay and since day one, the rotary encoder had a slight problem. I had to turn it slow to register correct values. If I rotated it quickly it would jump 5-6 values behind every 5-6 values (so it didn't go anywhere).

I decided that I would fix it and gutted the machine.. pictures follow:

The faulty encoder can be seen in the following picture:

The pads are velocity sensitive and this is how it works: there are two contact areas
and the rubber pads have the graphite layer that correspond to these two areas in different heights. So when you hit the pad, the MC measures the time it took to close both switches which corresponds to the velocity of your hand.

This is the encoder. Close ups:

The part can be found at mouser as pt.no. 688-EC12E2420802 (alps 12mm rotary encoder) and it costs only 2 bucks. It is very simple to replace it, you must have a solder pump though to cleanly remove it.

Things to remember:

*) when you unscrew the machine, make a note (NOT mental) to the whereabouts of each screw..
*) the order of removing the components is the following: 1. the PSU, 2. the IO board, 3. the sound engine, 4. the "DJ" slider (the big one), 5. the mains outlet and 6. the main board.

some connections (eg the one marked with x) need not be disconnected. You can put the IO board aside for a while.

Good luck if you have the same problem.

Good choice if you have an MC-909 instead of an MC-808 :)

Now my MC-909 is like new.

Just got it in the mail!

2008-12-01T23:11:00.001Z

A QY700 in very good condition! We both loved it so today (and possibly tomorrow too) is a play-day

If I find some space, it will permanently placed side by side with the MC909 and the various non-paneled (yet) things I've made.

I was SO lucky!!! I found some 3.5" disks!

For anyone curious to hear how it sounds, there is a demo mp3 here

IT'S ALIVE!!

2008-11-30T22:53:00.001Z

The connections have been made and some simple software has been written to map keys to notes. There are some issues that need to be sorted like transpose while pressing keys etc. The concept works! It is a very nice and cheap way to experiment with such a keyboard.

It feels a little flimsy though, pressing buttons against an unsupported perfboard so the top priority now is to find a case that will make the keyboard right at home! I will add some knobs too. There is much (programming) space for them

So, stay tuned for a first video demo as soon as possible. The only thing I need right now, is a little practice!

The proof of concept

2008-11-26T23:24:00.003Z

This is the keyboard from the last post with some additional stuff. There is a Core module (midibox.org) and a digital in midibox module that reads the switches. I installed the SDK so I can write a minimal program (midibox is programmed in C and produces hex files, uploadable as system exclusive data to the core). So I connected 4 of the switches to make a quick test and connected them all together. I was sure that both midibox modules were ok because I had the midibox sequencer running on them. The simplistic program just adds 40 to the pin number (the one displayed on the LCD) and outputs this as a note on/off midi signal. When all switches get connected, there will be a need for a mapping between module pins and note numbers so there will be some more programming. For now, a small, quickly made video shows that IT WORKS!

(first video for public viewing, so don't be so harsh :)

You can also see it in vimeo here: http://vimeo.com/2357167

Harmonic table keyboard

2008-11-25T22:35:00.001Z

This is another project I just started working on. It is a keyboard/MIDI controler based on the harmonic table (like the c-thru music controler). This one is just switches which all connect to a midi core module (from ucapps.de) which translates the various keypresses to midi signals. There are 50 keys/notes and although I'm going to use letra-set rub-ons to write the notes onto the keys, you can make out which note is which from the blue keys. They are in pairs and one of each pair (the low/right) is an A (La for europeans) and the other is a C (Do). In the harmonic table layout that the C-thru axis uses (and others) , if you choose one button, the button above it is a fifth, the one to the top/right a minor third and the top/left a major third. (you can see c-thru's chord calculator here http://www.c-thru-music.com/cgi/?page=layout_ccalc).

The other keys have the following functions: The red keys on Braska's left "hand" are a row of 11 buttons that instantly transpose
the whole keyboard from -6 to +5 semitones The middle one, a bit spaced appart, is the no-transpose button. The other 2 red buttons are octave up/down and there is a generic slider under his right hand which is assignable to modulation, pitch bend or whatever CC you want. The blue button under his belly is the menu button. There is a 16x2 LCD screen displaying various bits (transpose, octave, pressed key etc) but the software is still in development stage. As soon as a workable version is at hand, I will publish it of course.

The needed hardware is a lot of switches, a midibox core module, an analog in module (for the slider) and two digital in modules for the switches. I have these already made for the midibox sequencer (who still lacks a panel) until I etch some more. http://synth-diy.blogspot.com/2008/10/midibox-sequencer-v33.html

So the following days will hopefuly see a working HT controller. But until then, good night, Braska!

STAY AT 440 Hz!!!!

Braska explains the midi thru schematic

2008-11-17T22:57:00.002Z

Ribbit....................

Midi Thru Box

2008-11-17T12:33:00.002Z

I desperately needed some through ports for devices I have that have only in and out ports. So this easy project was done in a single worknight (after putting kids to sleep, 2 hours at most)

It is no compicated design. You just have to get the midi input (using the optocoupler like all midi stuff I've made. Based on ucapps.de midibox design). Then buffering it through two subsequent logic inversions of the signal. One of the outputs goes to the LED for visual feedback. The others, like any midi output fed from 5V, gets a 220Ohm resistor and it is imediately made an output.

I will post schematic later in the day because I have to scan it and I'm too lazy to make it on eagle (it is on paper). If there is a need for a PCB (even though it is a very easy project) I can provide one. I may even make it on a pcb with multiple in/outs (3 in / 9 out eg :)

Say hello to my model: His name is Braska and will be posing on my stuff from now on! He is a cute guy and posing is the only chance to take a break from being beaten, tortured and gummed to death by the kids.

Modular synth PSU

2008-11-11T22:09:00.001Z

Went today to the shop to get many 150k and 75k resistors to finish the AVRSynth32 but they didn't have enough. My eye caught this fine toroidal transformer of 50VA (I know it is overkill!!!) that outputs +15V, -15V and common ground. So I decided that since I am going to build some yusynth modules, I should have a PSU at hand when the time comes.

The design followed is like the ones of ken stone and ray wilson (PSUs are not THAT complex) so for more info you can go here and here. Cautions apply as you will be working with lethal currents if you decide to build such thing. A note to perfboard makers like myself. The pinout of 79xx is DIFFERENT of the 78XX. For some, this may seem obvious, but for others, if they dont pay attention to the pinouts, they have surprises coming! The regulator might get extra hot and/or explode. Had done this some time ago with a 5v regulator (7905) and when I "checked" it if it was hot (using my finger) I left my fingerprints on the regulator (along with some skin layers that got roasted).

Making it on a perfboard is very simple but BEFORE you plug it, use your multimeter to search for any shorts that might damage the circuit and use a fuse on the mains part of the transformer.

As all sites that have such projects mention:

Disclaimer

A note to readers:

All electronic projects and designs presented on this web site, or associated web sites should be considered dangerous if not lethal if not used safely. When working on projects based on these designs, use extreme care to ensure that you do not come into contact with mains AC voltages or high voltage DC. If you are not confident about working with mains voltages, or high voltages, or you are not legally allowed to work with mains voltages, or high voltages, you are advised not to attempt work on them. The author, host, and all people associated with these web pages disclaim any liability for damages should anyone be killed or injured while working on these projects, or projects based on these designs, or any other project or design presented on these web pages and any associated web pages. The author, host, and all people associated with these web pages also disclaim any liability for projects, or projects based on these designs, or any other project or design presented on these web pages and any associated web pages when used in such a way as to infringe relevant government regulations and by-laws.

(this also taken from ken stone's modular synth pages)

AVRSynth board update

2008-11-11T07:30:00.001Z

This is a first step towards completing the board. The odd part is that one of the ICs is soldered on the bottom side. This was a clever thought Collin had as it reduces bridges to 5 total from at least 15. As I realized yesterday, I had put no values to most of the components, so tonight, an updated version of the board will be placed online with the values written.

Not all R2R resistors are in place as I ran out of them. So it might be finished tonight. The thing is that soldering resistor ladders is SOOOO BOOOOORRIIINNGGGG!! I should have used a resistor array.

Another thing I should mention is that the board can work with both AVRSyn 16 and AVRSyn 32 firmwares and processors. So I placed a female pinheader in the place of the crystal and I can test both of them before commiting to AVRSyn 32 and it's 16MHz crystal

Hope to have updates soon....

AVRSynth 32 PCB

2008-11-10T10:32:00.002Z

Collin Mel and myself , have designed a PCB layout for AVRSynth, instead of doing it on perfboard. It hasn't been proofed and debugged yet but I am on the process. If you feel adventurous and/or lucky, you can download the eagle files from here
and try yourself!. Please do tell me about possible bugs you may encounter.

I exposed the photosensitive board covered with a transparency with the PCB layout printed on. I used two transparencies, one stacked on top of the other for extra opaqueness. Still there is a little UV light going through, you may see it on the photos as the copper is a little spotty. No electrical flaws though, but I think, another layer would do a better job.
I developed the exposed board with a solution of 1 teaspoon of pipe cleaner (branded TUB.O.FLO locally) but which contains NaOH. When developed, I etched it using a 14% HCl solution (also a cleaning product) and dropped in it a small cup of concentrated Peroxide. (Named localy "Peridrol"). If interested I can delve in much more detail on the etching process. Just be ware of the fumes and liquids, so work in a well ventilated area, stay AWAY from children (you and the chemicals) and store them out of their reach. These chemicals are highly toxic and caustic and I don't want to be held responsible for any misusage of the components.

This is how it looks while ethcing.. Beware of them bubbles. They stink and for a reason. DO NOT inhale close to them.

This is the finished PCB, without any components on it. I will post photos of the component mounting process and hope it works the first time :)

When this is finished, a core midibox module will take care of the midi messages that are needed to have access to the AVRSynth32 functions that are not available through it's pots. (such as cutoff, resonance, ADSR params etc.)

AVRSynth 16 Panel

2008-11-10T09:24:00.001Z

The AVRSynth has officially its panel. Drilled on a 3mm aluminum sheet sized at 27x21cm (almost an A4). It was a little difficult to correctly align the holes when drilling them because the drill bit had a tendency to drift off and walk away. The result was a random offset of each hole at about 1mm (in random directions that is.).

Nevertheless, a panel I had made earlier was printed on photographic paper. To align these two, I punched small holes at the centers of the knob positions and turned it facing down (the paper) so I could see through the aluminum holes that it was all aligned (or at least there were no big offsets). I glued it with simple roll on glue and transfered the buttons and knobs from the cardboard panel they were on, to the aluminum one. Now it is a little mess underneath the panel but nevertheless everything works as planed.

I passed it's output through MC-909 effects and it sounds wonderful. Even raw, it sounds pretty nice. I might make a demo with sounds coming out of the AVRSynth 16.

The svg file for the panel layout is here

Stay tuned for updates on the AVRSynth 32 + midibox project.

A family photo (extra members not shown :)

Switches!!!!

2008-11-06T21:57:00.001Z

Switches came. Tact switches for many purposes... The midibox Seq waits for some of them. The c-music axis clone, for most of them, and maybe a mini keyboard for one of the synths. Hey you could even make a guitar fretboard with them, they are just the right size.

For making stuff with switches, midibox ruleZ!!!!

An AVRSynth 16 layout

2008-11-06T21:15:00.004Z

I made a layout to be printed on photopaper and be glued on an aluminum panel. I can't process the aluminum sheet by myself so I resort to glueing photopapers allover the place. :) So,
this is it, it has 8 knobs, 16 switches and volume/power and it will be ready with pots on sometime in this week.

You can find the original svg (made with inkscape) at the file repository here

babyBotte repackaged!

2008-11-03T21:49:00.005Z

This is the new babyBotte. I decided against the cardboard shoebox and dumped it. So I got a TRIPP container set from IKEA at first for putting the babybotte on the small square one and an 8MHz avrSynth I have lying around, inside the bigger one. My wife gave the idea of putting the babyBotte inside the round one.. So, I designed a panel that I would print on photographic paper and stick it on top of the lid and open holes to it to insert the pots

The small holes are for the square buttons. I used a high speed cutter to make the rectangle cuts.

Also, because the box was a bit high to grip it easily, I marked it at about the middle and cut it with tin scissors (the TRIPPs are made of a rather thin aluminum sheet)

and then I cut the rectangle holes:

To align the holes with the printed layout, I printed a draft, black and white copy of the layout and stuck it on the lid. Then, using that as a guide, I opened small holes which little by little I opened them to the diameter of the pot shafts (10mm in my case).

The layout of the buttons and the panel "design" is available at the file repository (here) .

Then I opened small holes on the printed paper and alligned the holes while letting the glue set.

Using an exacto knife, I opened the holes on the paper

and put pots and switches:

The (still) tricky part was to mount the led. I fixed it with hot glue. It is a bit flimsy but I do not intent to take the babyBote v2 to any live gigs.

So the finished bb was something like that:

or like that

.

The samples still remain the same as the bb survived the move.

The only thing that remains to be seen is the durability of the photopaper..

Small tune with samples from babyBotte shoeBox fraktalSynth

2008-10-30T21:58:00.004Z

I sampled two fraktalSynth sounds and added drums, bass, percussion, some riffs and TADAAAA!

It contains some mistakes because I was mixing it live on the MC 909 (which by the way have to get some synth porn pictures of it)

Here! Criticism accepted (Because I moderate the comments :)

Edit:

google sites apparently has limited bandwidth so I made an account on rapidshare. If you stumble to any problems please drop me a note!

so, go here: http://rapidshare.com/users/O5MTP0

Shoebox fractalSynth

2008-10-30T07:35:00.008Z

This is how fractalSynth looks like:

And this is how it sounds (a little tape delay added)

I had once stumbled upon Catweazle's fractal synth. In the circuit benders forum it seemed that the project had come to a halt. But recently I realized that it was going on elsewhere.! Here.
Also, the files can be found in the forum or in http://www.gjcp.net/~catweazle/PICsynth/
There are two schematics and lots of mp3 samples if you want to hear how it sounds.

I decided against building a PCB in eagle and then etching, soldering, etc. and went for the perfboard. It is a very simple schematic and I pulled through it with relative ease. Just remember to leave a little space around the MicroChip so as to put the simple filter and the voltage stabilizer (a simple 7805 with two capacitors, nothing special).

The schematic mentioned 10K pots but since they are used as simple voltage dividers you can go (as I did) up to 100k with no apparent malfunction. I used a lot of female pin headers on the board (as you can see) and connected the pots and buttons with male pin headers. This is rather flimsy as a connection. You might not be able to go live with such a thing but, it is quick and easy.

The underside of the perfboard is all connected with solder. A difficult to correct method but again, it is quick and I can't wait :)

I used a cardboard box because it was the only thing I could find around me at the time. I had some aluminum panels lying around but I would make noise and the kids would wake up. I have mentioned again the problem I have, making panels for my stuff.

Now I have a noisemaker in a shoeBox :)

I added a simple voltage stabiliser with a 7805 and two electrolytic capacitors and fed the voltage to the chip.

The pots were mounted on the cardboard (a tedious and dangerous job because the cardboard was thin and there is always the risk of ripping it appart.) and soldered with wire and pin headers.

Some special attention was given to the 7-segment LED that connects to the chip. I used 150 Ohm resistors instead of 200 Ohm mentioned in the schematic. The difference is not a big issue. (It would be if 10 Ohms where used for example). The resistors where directly soldered on the led pins because I wanted no other things than the led on the top side of its board in case I wanted to glue it on the cardboard.

So it looked like this:

The whole thing was put in the box after determining which pin of the led went to which pin on the chip. This made the wiring a bit of a rat's nest.

So the final "product" was firmly closed to hide the ugliness of it's interior.

The first tests were a reality.. And it WORKED!!!!!

The next step was to figure how it was working.!!

A big thanks should go here to Catweazle (you can find him in electro-music.com forum) for releasing the source code as well as the schematics. I put a programming header on the board so as to try some things myself.

The next thing is to put the shoeBox fractalSynth through my MC 909 and make a tune out of it !!

Dissecting SY 77

2008-10-28T21:46:00.002Z

I had an SY-77 lying around in my old house so I decided to take it appart just to look how it is built and what is made of. It wheighs around 15 kg and it is a very solid built. You have to unscrew at least 14 screws just to remove the underside panel which reveals the electronic guts of the instrument. There are two main boards visible. Both have countless DIP chips and some surface mount giants. Of course, it is well over me to make out what each of the chips actually do so I was just staring at them in awe.

The SY was the flagship of Yamaha back in the 90s. It had 32 voices, 16 of them where AFM (an advanced kind of DX's FM synthesis with more algorithms between the operators and the ability to feedback an operator with it's signal) and the other 16 were AWM (a PCM like sample playback synthesis method). Each voice signal could have two resonant filters and the output of the AWM voices could be used as input to an FM operator. This, if you didn't know what you were doing, was usually a noisy mess. I didn't but the guys that programmed the presets did because it has some wonderful mininoog style sounds that became very expressive with the velocity/channel aftertouch, semi weighted keyboard the SY features.

Moreover, in its FM synthesis, a different envelope (both pitch and amplitude) could be assigned to each of the FM operators so you could program some evolving sounds. Its envelopes featured repeat points and so on.
The SY also featured an on board sequencer which I didn't really like (It was the time of cubase on atari ST). But my SY grew older, some keys grew sticky, some sliders were in need of repair and it gave way to the VST stuff. The floppy drive died a horrible-sticky death (there is a rubber band that used to turn the disk but it just disintegrated in my hands leaving a sticky, tar-like residue. I cleaned it with acetone but I need to find a replacement now).

I put it back in its case, waiting for the time to move to a bigger house where it will take the place it deserves. A master controller maybe? Or maybe not?

For more pictures and closeups of the ICs you can always look here

QY Synth porn pt 2

2008-10-23T22:49:00.005+01:00

This is the bottom of the main PCB. Is it bendable?!? ;)

Some synth porn

2008-10-23T22:45:00.002+01:00

Dissecting the QY 70. Nice piece of gear. Would really like to know what are those chips anyway! (filters/roms maybe ?) The big one in the middle must have the OS.

A dsPIC33 breakout box.

2008-10-23T12:49:00.001+01:00

Made this in order to test the samples I (again) got from microchip... (coolest guys in the world.. If I ever make something sellable in huge numbers with a microcontroller, it will surely be a PIC :).

I include the brd file of eagle so you can make it yourself (it is tested that it works). If you want you can print the bottom layer on a laser printer and then iron the paper on the back side of the board so you can have the pinouts printed on the top side..

files as always here

AVR Synth part 5 (final)

2008-10-23T12:44:00.001+01:00

The connections are simple now.

It got a little wiry but it plays alright.. The following sample is a single note (until the end where I start to improvise :)
The loop is made by the envelope only (decay time)

The original site of JAREK ZIEMBICKI is here
There is this other guy named krüe who modified a little the hardware (used an atmega 32 instead of atmega16 and a 16MHz osc instead of 8MHz) and added a lots of features. Source code included! here

A note. I found that the code on Jarek's site didn't work with my atmega16 so I got the hex file off here where they also sell ready made boards.

My sample is here

AVR Synth part 4

2008-10-23T12:37:00.001+01:00

The switch multiplexer.. lots of diodes

and cables

AVR Synth part 3

2008-10-23T12:35:00.001+01:00

midi interface (a little deviation from schematics here since I didn't have a P900 or 4N25 optocoupler at hand and used a 6N138/9)
The (typical) power supply. 5v with 7805

AVR Synth Part 2

2008-10-23T12:34:00.001+01:00

This is the Digital to analog converter. It uses lots of 1% resistors. The schematic mentioned that for the most significant parts, 0.1% resistors should be used but I didn't use such. It really has no effect on sound (at least for me that I didn't expect anything special).

Again, a little attention to the schematic, can save you from a lot of bugs later...

AVR Synth Part 1

2008-10-23T12:30:00.002+01:00

I decided to make JAREK ZIEMBICKI's AVRSYN. But there were only the schematics and no board layout so I had to make my own. So I started laying it out on eagle but I got on a deadlock due to the fact that I didn't want to make a double sided board. I would etch it myself and double sided boards are a BIG pain in the but (vias and such, alignment etc). So I made it on a perfboard. But before that, I decided that it should be made into discrete modules. One for the microchip, one for the D2A (an R2R resistor ladder type) , one for the midi interface, one for the power supply and one for the switch multiplexer.

Here is the main part. I put pin headers to wherever it would connect to another module and got myself a lot of ribbon cable. The AVR is a really simple design. Only the layout makes it complicated. It can be made by anyone (Even I made one!!!).

Serious Programmer

2008-10-23T12:22:00.001+01:00

At least more serious than the one I had before.. The pickit2 from microchip (I felt guilty for all the free samples I got so I bought the original, but there are clones on, you guessed it, e-bay!!!). It can program a much wider range of chips, namely the 16Fxxx and 18Fxxx and also the 24Fxxx, dsPIC30Fxxx and dsPIC33Fxxx (and the PIC32 but I never got to try it) . The good thing on these chips is that the dsPIC33 have Digital to Analog conversion on board at 16bit and can go to more than 110KHz sampling rates. MUST-TRY!!!!

SMD!!!!!!!!!

2008-10-23T12:18:00.001+01:00

A (failed) experiment: I got 18F6621 samples from microchip.com (I LOVE these guys!!) and they are packaged in a TQFP64 package (a very dificult to use package if you are not a machine) so I decided to make a breakout box. Get those pins in pin header format so I can stick whatever I want to them. But I failed miserably. The design was haunted by the 8mil distance between the legs. It proved more (less) than my etching method could handle so I had heavy crosstalk between the leads.

And the soldering was no easy job too!!!!!

But if you feel adventurous, there are brd files you can use to despair on your own :)

Micro-Modules

2008-10-23T12:08:00.002+01:00

This is a serial communications module (using the UART that exists inside the PIC 18Fxxx, It just changes Voltage levels so your 5v microchip, doesnt get fried by the serial's +-9V

This is a simple 7805 on a perfboard. Giving stable 5v to your (my) test circuits and breadboard projects.. I recently made a 3.3 V version for experimenting with the dsPIC33 family.. (more problems with these to follow :)

Well well look what we got here :)

2008-10-23T12:05:00.001+01:00

I MUST finish it. (and of course, it's panel :(

MidiBox Sequencer V3.3

2008-10-23T12:04:00.001+01:00

These are the core components, etched, soldered, placed, programmed, working, but lacking a nice panel to sit on. This is my weak spot. .. Panels...

A big thanks to T. Klose and ucapps.de for exisiting :)

MFOS SoundLab

2008-10-23T12:00:00.001+01:00

Lying somewhere inside a box is an almost-finished Sound lab. (lacks pots which I am still waiting for). I bought simple square aluminum panels 21x27cm each for 2 euros apiece and decided that the panel will be as shown, printed on photographic paper and stuck on the aluminum since I have no other way to make it better.

You can find the SVG (made with inkscape) here

Side projects

2008-10-23T11:23:00.001+01:00

This is an octal RGB clock. I made it so it can be impossible to actually tell the time but nevertheless its beautiful (in its own way).

There is an atmel AtMega8 µCU and 6 RGB leds. Two for hours, two for minutes and two for seconds.

Each led can be Red, Green, Blue, or a combination of them. So you get eight colors, Red, Green , Blue, Magenta, Cyan, Yellow, White and Black (all off)

Lets say now that a led (with all its colours) is a binary number and Red is bit 0 (rightmost), Green is bit 1 and Blue is bit 2. With the above combinations you get a number between 0 and 7 (hence the octal part) . Two leds can count up to 64 this way. So you can count easily up to 60 seconds (and minutes)

eg: the time on the second photo is:

Red, Cyan : Green Cyan : Red Green=
1x8 + 6 : 2x8 + 6 : 1x8 + 2 =
14:22:10

Nice eh?

(wouldn't sell though : )

A working core module

2008-10-23T11:15:00.001+01:00

PCB Oven output.

2008-10-23T11:11:00.001+01:00

Both are midibox core modules, both are working even with the slight fixes made on the right one . One serves now as the brain for the sequencer and the other one for more experimental stuff. (That is: my non-working programs :)

CORE module and TV

2008-10-23T11:05:00.001+01:00

The midibox Core module is a monster of usability. It is a hardware core component and a software library that can turn the chip into a powerful midi/controller machine. There is a very active community that writes programms and creates modules and applications. The mastermind behind the midibox is T. Klose (and I wonder what kind of guy he is, providing such stuff for FREE!!!! )

So, there is a small application that turns the core module into a video signal generator with the apparent results shown above. I put it in the core and caught myself staring at the results in awe! (and then reprogrammed the core to do something more useful :)

Making of the UV Oven

2008-10-23T10:40:00.001+01:00

To start, I had to make the array permanent and to such dimensions so as to have even lighting all over the surface of a typical photo-resistive PCB. So I laid them as shown, taking into account the distance of the leds which was enough to have overlaping beams of all leds. (so no blind spots where created) .

This was put in a ikea FIRA box, slightly modded for the purpose. (I left only the bottom drawer, didnt put the mid panels and used one of the mid panels as a swing door, attached to the top of the box with safety belt ribbon, glued and stapled to the box and door)

The first test consisted of burning two photoresistive boards with components needed to make MIDIBOX sequencer v3.3 . It was a total success. as it can be clearly be seen.

Before going into burning the midibox sets , I performed some tests. The results were as such.

* With the current setup (35 UV leds (UV =395nm) at about 20mA each from a distance of around 30cm) the board needed around 15 minutes to be developed
* Reasonable results were between 10 and 20 minutes
* The film used was simple inkjet transparency but I would print it TWICE (my printer is accurate enough) or use two printed transparencies one on top of the other

They were then developed using the standard procedures (NaOH in water for removing excess photo resist and then FeCl3 or Sodium persulfate or whatever you are used to)

The results were AMAZING. The Oven was (and still is) one of the most important tools in my "lab". (The timer was dumped, I had a watch and pulled the plug)

PS. The array of leds needed quite a lot of current/voltage and I was lucky to find a hewlett-packard printer transformer with 1A/37V output.. Don't test THAT with your tongue!

First (UV) rays of light

2008-10-23T10:21:00.002+01:00

This is a test:) I had to make an array of UV leds and calculate properties. I made a simple excel file (openoffice format) to calculate these things here .

Board oven timer

2008-10-23T10:03:00.001+01:00

Not exactly synth-DIY but this is a timer I made for my soon-to-post PCB oven. You just set the time and keeps track of it, switching it off when it must and securing it from accidentaly opening the lid, saving my eyes from UV burn :)

Everyone must start with it :)

2008-10-23T09:58:00.001+01:00

This is a Weird Sound Generator (Bought the board from ray wilson of musicfromouterspace.com). It was interesting at the time, making all those bleeps and blops but I soon got over it. So soon, I didn't take the time to put it in a proper box. I even pulled out the knobs to reuse them elsewhere so now it stands naked in a box among other stuff...

the "lab"

2008-10-23T09:54:00.000+01:00

This is my "lab's" setup at 7-13-2008. Minimal, as my electronics knowledge was (and still is)

Pseudo-digital oscillator

2008-10-23T09:52:00.001+01:00

An old project of mine (6-12-2008) was to have a counter run through a series of voltages and make a waveform out of it. There is a pulse generator and a counter at the bottom part of the breadboard and decoders at the top. It never worked right so it was dropped. I tried to use the TINA simulation software to have a working version at least theoreticaly so if anyone wants it just drop me a note...

Training day (night)

2008-10-23T09:46:00.001+01:00

Got a PIC (microchip.com) programmer off ebay (I wonder what I would do without ebay here is its anthem).

It is a el-cheapo clone, (cheapest USB programmer I found) able to programm only 8-bit microchip.com microcontrollers (such as the 16f84 and 16f877 and 18f452 that the good guys at microchip.com sent me as samples). I tried almost every language available for them (like picBasic pro etc) but settled for microchip's own compilers (namely C18) which also comes in an educational edition that has optimizations disabled. No problem there. Since my C background is much better than Assembly, I felt right at home

Another piece of history

2008-10-23T09:30:00.001+01:00

This one was bought (also) from ebay and still is a beloved piece of equipment! I love it so much and have it beside my bed so I can play a note or two before falling asleep. Have played a lot with it using an external keyboard (an X-Board 49 from EMU) where I have set many voice parameters to its knobs. So you can play with attack/release, cutoff/resonance chorus/reverb, mono/poly/portamento etc. It gets very interesting when you remove the attacks from pianos and plucked instruments and instantly turn them into distant reverb-filled pads.

There is this guy that has some info on which controllers map to which attributes and there is a plan on the back of my head to make a controller for specific parameters of the QY using the MIDIBOX. (www.ucapps.de)

QY is a real jewel and made me love freezepop.

RM1X RPLCMNT

2008-10-23T09:18:00.000+01:00

I sold my RM1X so as not to have any guilt buying this little monster! Off ebay ofcourse. Does LOTS of stuff but I still (also) miss my RM1X....

NEVER sell your synths

2008-10-23T09:15:00.000+01:00

These are the photos of my RM1X. They were used to SELL my RM1X on ebay. Now, I look at them in despair that someone else has it and I don't. My moto from now on is: NEVER SELL YOUR SYNTHS!