/diy/ - Do It Yourself

repostan because I didn't notice you already made a new thread

Also, what do you think about making a blog with your progress to add to the sticky once you're finished.
then again, I guess the archived thread is enough for that.

Why don't you make it MIDI compatible? That'd make it so much more useful.

>>245920

OP started from zero. As in "how do I make an oscillator" zero. Considering his schedule and how the things have been progressing this far, I think he made the correct choice by going "simple" analog way.

Okay.

I have been awake for 17 hours now, and I have been working for 15 of those hours straight. I had 400 calories for the duration of that period. I am very tired but I made a milestone.

I made the first prototype module.

There are no components in it, and the PCB board is empty. But everything fits together and there is room for everything. I dont have springs yet so the buttons are just laying on the top.

A bulk of the work tonight has been designing all the vectors and shapes, and taking measurements, etc.

Stuff I learned:

1. I need to put more holes on stuff. Wires need to enter and leave many places and there arent enough holes for these wires to enter/exit.

2. I might not even need to glue it together. All the pieces fit together so snugly they dont fall apart. Everything will get even more snug when I have 9 of these modules side by side next to each other. In addition I can enclose all the modules in a little box/frame that will make sure they all fit into place perfectly. An advantage of having no glue is that I can disassemble it with no damage at all.

>>245920
>>245924

Ha, yeah, midi technology is probably more complicated than my entire device.

I would have no idea where to start.

I have briefly entertained autonomizing it, but, not in any sensible way. More like a grid of solenoids to lay on top of the keys.

What kind of amazing future contraption have you been using to cut everything?!
Post pics.

>>246012
Lasercutter dude.

>>246012
>edges are all precise and burned

Water jet, obviously.

yeah random /b/tard here. I stumbled into this thread because i had a friend in here HMU about this. WHats the point of it all? whatever it is seems badass. xD

You sir, are a total and utter Hero. That is all.

>>246012

I have been using the laser cutter. Which is like this $6000 box we have at the lab. Its basically a self contained area where a computer controlled infrared laser cuts material for you. Its most effective at cutting/etching wood and acrylic.

I am basically a pro at using it at this point. Its always a really interesting experience operating the machine. Tonight I think I did a poor with some of the pieces. Wood is interesting in that it varies a lot from piece to piece. Meaning one piece of wood might need 40 watts to cut it, but another might need 60 watts. A lot of these pieces I cut tonight changed density mid cut.. If you look closely some of the pieces are missing slivers of wood. The beam would cut all the way through for most of the piece, but it would reach a density that it couldnt cut through and I would have to force it out. Thats why.

>>246014

Speaking of those burnt edges. I could sand it off and make it white again. I just dont.


>>246023

Thanks!

>>246025
I noticed in the last thread that you're using a 741 op-amp
please no.
Those things are horrible, use a tl071, those things are a lot more effective for audio situations

>>246025
>Wood is interesting in that it varies a lot from piece to piece

Natural materials are never uniform. The closest you'll get to uniform with wood would be something highly manufactured like MDF.

(don't laser MDF, it goes up like flash paper given half a chance)

>>246012

Regarding the machine itself here is it arriving in the mail from China:
http://www.flickr.com/photos/hslphotosync/5938903959/in/photostream/

There are lots of good shots of people using it but I dont want to link to them directly. If you search around the heatsync photo-stream you will find a lot of good stuff.

>>246032

I considered a bunch of options. The design I did decide on has no op-amps.

I think I made one oscillator with a TL-082. It didnt work very well.

>>246031

If I am not mistaken, we have used MDF successfully. I have seen particle board go through.

>>246036
So you used transistor based oscillators?
that is quite the unstable solution, it might be too late to tell you this but do note that the gain of transistor based systems is based heavily on hfe, which is unfortunately effected quite drastically by temperature, so you might get quite extreme changes in your output levels depending on how much heat is being dissipated from the system.
you have two things I can suggest.
add a compandor before the final output stage (a compressor op-amp) or create an LC based op-amp oscillator, those are more complex but will be a lot more stable and effective.

>>246049

I appreciate your advice, but I have been pretty successful building it. I even shot it with a heat gun from an inch away with no noticeable change.

But I dont know, you could be right. Its not the first time I have heard to be aware of temperature problems. Which is why I have been pretty cautious in my tests.

>>246069
I'm so excited now for the final result

>>246069
I'm interested in this "heat gun" you have mentioned.

>>246025
>burnt edges
So you plan on keeping the burnt edges look? I think I like that. Although I would finish the visible parts with some more or less clear wood finishing. And the burgundy, navy and cream white colored buttons look pretty good. I assume these aren't the final color, but I like it nonetheless.

I forgot to mention. I met up with Mr. F this morning and showed him my circuit design. He gave me the thumbs up. Now I need to familiarize myself with surface mount soldering.

Things that need to be done:

1. Solder
2. Get some springs

>>246173

Its like a hair drier that is extremely dangerous.

>>246124

Thanks.

>>246174

Well, no I dont plan on doing anything about the burnt edges, but everything I have made so far will be an internal part not visible on the final product. Ill varnish it and everything nonetheless.

Regarding the buttons, thanks. I just stuck some acrylic in there. On the final product I want to use colored metal inlayed seamlessly into wood.

As for what metal to use I am not sure. I kind of liked the idea of using three kinds of metal for three different colors (brass, aluminium, and copper). But recently it became apparent to me that I can anodize aluminium into different colors. So that gives me more options, but I am not sure I want to do colors per se. It would look really cheesy if I had red white and blue, or red blue yellow or something.

I am open to suggestions on this. But whatever I do it will look a lot better than those the buttons I just threw together today. Everything will be all stained and fancy.

>>246178
>It would look really cheesy if I had red white and blue, or red blue yellow or something.
Presumably, yeah.

Well you can photograph it once you're mostly finished with the outside and experiment with photoshop

Hey, it's split-octave guy! I found your thread again!
Your project is looking very... tall. You're going to need a taller chair if you ever want to work with this thing. Also, I absolutely need one of these things. Don't worry, richfag here.

>>246069
or you can just save the entire hassle and look for really temperature stable transistors.

>>246284

Yeah.

The thing about piano keys, is its very easy to just put to the acoustic or electronic mechanisms behind the key. But if I have a grid my best option is to put it below the keys.

I dont know if you get a sense of scale. Its less than a foot tall I think. So I hope it can still permit sitting while playing.

>Also, I absolutely need one of these things. Don't worry, richfag here.

Cool! Keep posting. If you are really interested we can talk when I finish the first one.

Hey does anyone know where I could get some custom made springs? Or at least a vast selection of springs?

I contacted two companies and neither of them have responded.

>>246604

I don't know if wave springs are suitable for your instrument, but at least Smalley has a quite wide selection and they've been willing to answer stupid questions. They even offer samples of their springs.

Other than that, shops specializing on screws seem to have springs quite often.

Have you considered using rubber blocks or rubber tubing as a spring?

>>246669

Wave springs? I have never seen those before. Those would work.

I dont really care about the specifications, I just need it maybe 4/5ths an inch tall and about half an inch in diameter.

Rubber sounds cool, but, how compressible can rubber get?

I have been to ace hardware and home depot. As great as their selection is they just dont have what I need.

Thank you, I will look into what you said.

I looked into smalley.

They had a spring the right shape and size, but it had like 12 pounds per square inch of force. I need like zero pounds of resistance.

Okay two things:

1. I just found 200 cheap springs on ebay that roughly met the parameters I am looking for. I have no idea if they will be too stiff or what. Just going to hope for the best.

>>246895

2. There is only 1 thing.

>>246897
I chuckled.

I got some parts from Mr. F while I was hanging out with his engineering friends.

Right now we have a heatsync labs we have a 4th of july party going on. Fun day in general.

I got some advice on surface mount soldering. Pic related.

>>247755
i've never seen such blurry pads, that might be a problem

>>247769

Heh, well, the camera had trouble focusing

Okay I just soldered stuff down.

Surface mount is hard.

>>247803

Oh shit nigger what are you doing?

Solder paste and reflow.

>>247808

We dont have any of that fancy high class solder paste stuff.

But yes, I should do that.

>>247808
You can traditionally solder SMDs... but not like that. Ugh, it make me sad. It's like electronic guro.

>>247809
>We dont have any of that fancy high class solder paste stuff.

You should. It's inexpensive and meant specifically for what you're trying to do.

Also ALL of these look like incomplete or cold joints: >>247803

It's possible to solder SMD with an iron and some rosin core but your traces and pads are huge. Soldering SMD on top of that much thermal mass is not for the faint of heart.

>>247812

Yeah I will give solder paste a shot.

I did run the multimeter through some of the resistors. I was happy to see that all the ones I tested worked out.

>>247803
Oh for fuck's sake.. that's some of the shittiest looking work I've ever seen!

1. Go to the trouble and expense of plating your PCBs. It'll make soldering components incredibly easy.

2. Surface mount? You NEED to have liquid solder flux. Put down a little flux, then the component, THEN solder it in place.

3. For FUCK'S SAKE, get your components on straight!

4. Consider using a PCB prototyping service instead of making your own PCBs. Frankly, they look like shit, and if you have them made you'll get nice things like solder mask and silkscreening, not to mention plated through-holes.

>>247868
check this place out, OP:
oshpark.com

learn a little Eagle CAD and git'r'dun. It's totally worth the effort, as you can get the software for free and then teach other people. Shit, tomorrow I have a gig lined up where I teach this dude how to do it for $15/hr. The jobs line up when you're skilled. It just takes a little initiative, yo.

Well I did some tests. It didnt work.

I am pretty sure I mixed up the positive and negative sides of the caps. So I flipped them around and tried it again. When I plugged it in it just gave off a 60 hertz buzz.

To OP

All of this is fascinating to me, as a music major with a strong interest in engineering. However, all of this except the music part of it is Greek to me.

Where would I go to learn more about all this/where do I begin?
I'm excited about this, your project looks incredible.

>>247913

Tantalum caps have a mark (that line) on their positive side.
If you want to hand solder that thing, you could try at least the following:
1. Get good sharp-nosed pincers and use them to position and hold the components while soldering.
2. Pre-tin the pads, suck tin away with solder wick.
3. Use flux.
4. Use relatively large solder iron tip as needles have difficulties heating large pads.I usually use 1mm/40mil oval tip or 2mm/80mil hollow tip.

I personally often tin one of the pads (enough tin for decent joint), then add some flux and re-melt the tin while pressing the component's end into it. This is quite convenient, but be warned: particularly ceramic capacitor manufacturers say that this will crack the caps due to thermal shock.

>>247963

When I started doing stuff like this I was just in my garage with barely any tools, and a soldering iron. I didnt have anyone to help me either. I just tried making circuits and assembling wood into shapes.

When I was just screwing around in my garage I didnt realize this, but, knowing people and having tools are two really important things. That would be my advice. I spend nearly all my time now-a-days at this place called heatsync labs (http://live.heatsynclabs.org/)), which is what we call a hackerspace. Its like this community run space full of tools.

I also spent some time in classes at my local arts center. Community colleges and universities always have some one some where who can help you out too.

>>248008

Oh, they are tantalum? Thanks I didnt realize that. I thought the mark was negative.

Thanks also for the steps.

I will try pre-tinning the pads. I was using a solder wick a bit, and I was trying to hold them down but it was challenging.

>>247850
>all the ones I tested worked out

All that means is that the component underpads are in contact with the PCB contacts. It tells you nothing about the integrity of the joints.

>>248372

What? Like they will fall off eventually?

>>248382

Cold joints may become intermittent or plain break loose. Especially if they're inside something that will be handled, or if they experience any thermal expansion.

>>248410
Even I knew this. Sorry, OP.

>>248410

I see. I am considering buying some solder paste.

Nonetheless I am going to give this soldering stuff another shot. Be more thorough and mindful about what I am doing.

Some guy offered to do it for me. I will keep that in mind, but I would prefer to do it myself even if that means taking the time to get good enough at this.

>>248762

Sorry? I am glad you knew this.

You're so patient, OP. I would have quit by now and glued three keyboards together.

FYI I still don't know what you're making. It plays music, yes?

Did some more soldering. Think I did a better job. More progress tomorrow.

Also, I remember when I was looking around through a parts bin I found some resistors labeled zero ohms plus/minus 5%. Thats crazy.

>>249059

Yeah, its just a normal organ/keyboard/piano.

Except its got 28 tones an octave, and the lay out of the keys are different.

>>249760

Zero-value resistors are used to replace optional components so the circuit isn't broken with the optional part missing. The tolerance stamp is pointless but goes on anyway as part of the manufacturing process.

You could just bridge the solder pads instead, but in mass manufacturing it saves labor to use mass produced 0R parts and let the machine do the work.

>>249771

Reminds me of this cheap mp3 player I bought. Constant interference noise on the output.

I opened the thing and found 0-ohm resistors sitting where filter caps should have been. So basically the noise from the supply inductor was making it all the way through the circuit because some asshat at the factory wanted to save a couple cents per unit.

>>249774

That, or they wanted to differentiate their "expensive" products with better sound.

If you connect two resistors in parallel, the total resistance will be lower than the smaller resistor you use in the circuit. So if you connect two zero-ohm resistors in series you would have less than zero resistance in the circuit, meaning you would have negative resistance!

Science rules.

>>249818
Meant to say "If you connect two zero-ohm resistors in parallel" sorry bros.

>>249820
no. Theres no such thing as zero ohm resistors. The resistance is just negligible.

>>249818
This is completely wrong. Troll somewhere else.

>>249818
As much as you were joking, negative resistors CAN be built and used for cool shit like pic related.

Good news! I have 200 springs. And they feel good.

Bad news: so I need more than 200. I had been ordering 100 of everything because I need one per button and I have 100 buttons. But, I need 2 springs for every square inch, not every button. So I need 216 springs.

Gonna order more.

>>249818

>If you connect two resistors in parallel, the total resistance will be lower than the smaller resistor you use in the circuit.

This is true I believe. If you do the math with non-zero numbers this comes out to be true.

But if one (or both) of the values is zero its not true.

1/R1 + 1/R2 = 1/R

1/0 + 1/5 !< 1/5

Not that you can have 1/0 to begin with.

>>250200
*sigh*

...

For all intents and purposes (aside from current sensing, and high-current applications where voltage drop is an issue) a "zero ohm resistor" is "zero ohms", k? Mainly it's a convention employed to keep purchasing agents from having myocardio infarctions because you're specifying a 2mm length of wire as a resistor, and also so pick-and-place automated PCB assembly machinery has something the same size and shape as a *real* resistor to grab onto when assembling PCBs in mass quantities. LOL

>>250200

Oops I kind of butchers my description.

I have been ordering 100 of everything because I am buying one for every button, and I have 82 buttons. So I have 18 extra just in case.

I need 2 springs for each square inch. Most buttons 1 one square inch, but some are 2, or 4 square inches. The machine is a 6 x 18 grid, and while most buttons need 2 springs, some need 4 or 8. 18 * 6 = 108. 108 * 2 = 216. I need 216 springs.


>>250208

Yeah I believe that.

I also recognize that there is no such thing as a 0 ohm resistor in real life.

>>250208
>>250007
>>249870

>No fun allowed. No jokes allowed. Only serious business.

Hey guys this isn't /sci/. Take it easy.

Okay I just soldered this together (one of the left is what I just soldered, the one on the right is the older one). Think my soldering job was a bit more graceful, dont know if thats visible.

Havent tested it. Lets hope it works.

Aw man it didnt work.

:( :( :( :(

Okay so I know this isnt /diy/, and its not even real progress on my project (which I desperately need right now) but I discovered some crazy number stuff.

So all my tones are just fractions right? I am approaching all this music theory stuff from a purely mathematical point of view. When I see these notes on paper, I am not seeing A, A#, B, I am thinking about 1/1 9/8 6/5.

Each key on my piano has a fraction value. What I did (just for kicks) is divided each key, by the key before it. So to the left of 5/4 is 10/9 and (5/4) / (10/9) is 9/8.

I then drew out a new keyboard, and labeled each key with this value instead of its literal value.

Almost all of them are 9/8. And whether or not they are 9/8 follows a predictable pattern. The ones that arent 9/8 are either 32/27 or share the value of the first tone from various rows.

32/27 and 9/8 are kind of similar numbers. 9/8 can be written as (3*3)/2 and 32/27 can be written as (2*2*2*2)/(3*3*3)

I mean, I arranged these tones to be harmonically ergomatic, but, I keep finding these deep patterns of numbers that I didnt intend to be there. Shit is crazy.

>>250306
Well you have a scale of ascending pitches, all built on rational numbers, so a patterns seem likely to emerge...

Neat.

>>250306
bu... but this IS /diy/...

?

>>250314

Oh I meant like, the content doesnt match /diy/, not like my content was /diy/ and I am not on the board /diy/

>>250312

Yeah I guess thats true. I have been staring at these fractions for years now, so its funny to me by how different their meaning is to a normal person.

Its true, if you take a bunch of fractions, you could plausibly multiply/divide them to get more simple/elegant fractions. Thats always neat to see.

But, what I found to be most shocking was that this arrangement of 9/8 and 32/27 isnt random.

>>250264

Good lord.

PROTIP: Too much solder is even worse than not enough.

>>250264

Well, it looks bit better. The front trimmer's middle pin seems to be open (not sure about that) and it's not clear if the rightmost resistor is actually connected.

What are your primary problems with soldering? Solder not melting? Too big soldering iron bit?

Maybe you could ask someone to show you how it's made?

>>250264

And this is why you don't jump right into hand-soldering SMD as a soldering rookie.

You need to use less solder and more flux. All you need is for the solder to bond to the part, there shouldn't be any more than a fillet linking it to the pad.

Try lightly pre-tinning the pads where each foot of the part will go, then apply flux to that before placing the part and applying the iron. No additional solder should be required as the part should sink into and bond to the solder you left on the pads.

>>250273

Can't see very well but it wouldn't surprise me if some of the joints didn't take or you have unintended bridges. It's also possible you fried some components but that isn't always visually evident.

>>250264

>>250317

The front trimmer is connected. I know it doesnt look connected. When I saw the picture I had to double check on the real thing that it is.

I can get the solder melting, and my tip is actually pretty narrow, I have been considering getting a bigger one.

I have been getting some help from people, and I plan on getting more help.

>>250318

For this one I was tinning the pads before hand. Perhaps too much. I basically never added solder to it after I tinned it.

>Can't see very well but it wouldn't surprise me if some of the joints didn't take or you have unintended bridges.

I double checked all the connections for this possibility.

Surprise! Progress.

Assembled and wired a complete button mechanism.

Took a LONG time. Like a few hours. But a lot of this was modifying the design, and then figuring out ways for the wires to flow.

I need:
1. Wires of smaller gauge to bend more easily around corners.
2. Good quality wire strippers that can strip small gauge wire.

Also the shaft and the holes rarely fit right. What I do is make it too tight, sand it until it fits in. At that point it will fit in the hole but it wont slide gracefully. To make it graceful I have to press the button a few hundred times to wear down the wood. Its kind of annoying but its the only way I know.

The shaft has a bit of metal on the end of it with a wire soldered to it. The wire goes to the LED. When the shaft descends it hits an internal spring which has a piece of copper mesh laying on the top of it. The mesh is connected to power.

Probably could have assembled this way better, but I learned a lot about the best way of doing it.

Well I just broke the LED. Crap. That sucks. LEDs are fragile.

I did get some good readings.

1. When not depressed it had a resistance of 5m Ohms. Which is a ton. When fully depressed it had a resistance of 10k. Maybe with a second run through I can get the depressed value even lower.

2. It took a surprisingly high amount of depression to turn the LED on. Whats up with this? I guess I need to fix this.

OP don't get me wrong I appreciate your entuxiasm and efforts but srsly, why the fuck you are doing this, I mean fucking WHY.

You went apeshit OCD IMO. You are rediscovering warm water everywhere, in the least effective ways too.

You could just do it with like uh...0$.
If you had resisted the urge to make shit without learning it first, you should have learned MAX-MSP (or PureDATA if you don't feel like pirating sw) and just build a patch that generated just intonation frequencies oscillators. For the buttons you could have used the computer keyboard.

If you wanted to create your controller for it you'd learn Arduino to interface it to the computer.

The point is, learn to use existing technology first.

>>250502
I'm not the OP, but you do not belong on /diy/. GTFO

>>250502
This isn't OP's first thread on this subject.
I think the point was he wanted to do this completely analog with sinewave oscillators instead of sinewave approximation digitally synthesizing everything. Not that what he's doing is particularly unique, either, this has been done before.

>>250502
PureData is my life.
But you sir are a faggot and should leave.
OP is a Higgs tier human being.

>>250545
>sinewave approximation digitally synthesizing everything.
>sinewave approximation

>implying that a digital oscillator isn't tenfold more accurate and absolutely stable than a trivial analog osc with a bunch made of discrete components

like you know something about it, right?
Anyway I was in DIY erryday in the beginning, now I come back and I see autismal circlejerking all over.

>>250594
Get the fuck off your tower, /diy/ hasnt been around long enough to give credit to early adopters

>>250594
Oh for fuck's sake..
Nobody but OP is building the goddamned thing, why do you even care? YOU seem like the autistic one here, faggot; you talk like there's nobody else in the Universe but yourself, and we're all background noise or something. Fuck you and your shit. I may not think what OP is doing is necessarily the best approach, but it's his goddamn project and he can goddamn well do it any way he goddamn well wants to. If you don't like that then I suggest you take it up with your therapist and otherwise STFU, and by the way what are YOU building right now that's even noteworthy? Fleshlights don't count, either.

>>250615
>get off your tower
Is that an actual phrase in English? I know "get off your high horse", and "get off your tower" used in other languages, but I never knew it's used in English as well.

>>250594
>Anyway I was in DIY erryday in the beginning, now I come back and I see autismal circlejerking all over.

Translation:

>I saw the red news text at the top of /b/ and decided to check out /diy/. I left because /b/ is obviously better. When I checked this place out again it still suxors. aimiright kthx bai XD

>>245871
This is extremely cool DIY shit, OP. Keep it up. I love threads like this in /diy/. I wish there were more like this.

>>250622
>get off your high horse
>get off your soap box
>get off your tower
>get off your blog

>>245871
So OP someone mentioned something that raises a question: How are you temperature compensating your oscillators so they don't drift? Because, they will. Also analog components drift over time, especially potentiometers. You are using multi-turn potentiometers to adjust your oscillators, right? Anyway it'll be a bitch on wheels to keep this instrument of yours in tune if the oscillators drift, it'll take hours to sit there and tune each one individually before actually playing it.

>>250634
>it'll take hours to sit there and tune each one individually before actually playing it.

Most people that tune instruments get the hang of it very quickly. All analog-input instruments need to be tuned prior to playing them. Guitars are one example of them. When you learn to tune-by-ear, it literally takes a couple minutes max depending on how out-of-tune they are.

Oh wow I just woke up and I guess we had like a flame war or something. I'll partake in this!

>>250502

I have actually built arduino stuff before.

I would prefer to do the most practical thing. Even if I programmed a computer to do what I want I still wouldnt have the physical interface. So I would still have to build that, and arduinos dont have 82 pins.

I mean, I have no problem with computer technology. I think I have some preference for analog technology because, a purely analog device will never suffer from problems like processor or hard drive failures. Even Arduino's have a limited life. Analog stuff at least feels more permanent.

But yes, my primary concern is the precision of tuning an analog device.

>>250545

I completely agree that I am not doing anything particularly new.

>>250634

This has been the most common concern I get out of people, both online and in real life.

Regarding temperature, I know that the way its made is temperature sensitive. We shot a heat gun at it and it seemed to hold up pretty well. I asked my buddy about this, who has helped me a lot, and he said yes it will respond to temperature, but the capacitor values were high enough (low enough?) so that it was relatively insensitive to heat.

Regarding drift over time. Yeah it will drift over time. Not even due to the potentiometers or anything. But after 15 minutes or so the drift is insignificantly small as it is approaching a certain frequency (but never reaching). When I tune it, or play it, I will have to let it warm up for a period of time like 15 minutes. Really old synths were this way too.

I expect to have to periodically tune it. Hopefully not like every week or something.

>>250640
Yes, but: We're not talking about tuning 6 strings, we're talking about dozens of oscillators. It's more on a par with having to tune your piano every time you want to play it because it goes out of tune so quickly.

>>250729

Thats an exaggeration dont you think?

It wont go out of tune that fast.

Not that I can say for sure since I havent built it yet but I did do some tuning tests to see how long it can maintain a tune.

>>250848
The datasheets might have figures that give you an idea of what to expect as far as drift goes, might be measured in parts per million per 1000h.

>>250729
It is obvious you have no experience with this stuff at all and are merely making it up as you go along from ignorant hypothesis.

Basically, stop posting.

>>250848
I've been involved with music. It only has to be off a little for chords to sound completely wrong, and an experienced musician knows the difference and it'll drive them nuts.

>>251012
It is obvious that you're a jizz-guzzling summerfag child who THINKS he knows everything, while I'm an adult who has been employed as an actual electronics engineering tech for years and years, some of those years designing and building instrumentation so I damned well know about the temperature coefficients of analog components and how analog circuitry drifts with time and temperature.

Basically, eat a bag of dicks and die in a fire, autistic child. Nobody is interested in your uninformed, unprofessional opinions. Go back to hacking LEDs onto your computer and doing case-mods on your goddamned Xbox.

>>251093

Your lame rage doesn't sound that mature either, but whatever.

If the only problem with the OP's instrument is drift, he can always replace the oscillators with digital shit or build better oscillators. IMO the important things are the basic idea behind the instrument and the keyboard construction. It's interesting to see if the OP can actually play something worthwhile with it. Even if he can't, it's still an interesting project.

>>251149
See, here's why you pissed me off: I didn't tell the OP that his project sucked; I just asked him how he was going to handle an obvious technical problem. Then some motherfucking asshole like you has to start in with some goddamned dominance game just like everywhere else in this shithole of a website. So how about you fuck the hell off? I'd be just as happy if you got hit by a bus today and dropped dead.

I'll check back in a few days.
Maybe all y'all faggots will have settled down by then.

>>251161
>>251093
I am sorry we underestimated your technical skills, Mr. Anonymous. we'll be sure to treat all nameless posts as fucking gold now. thanks for the heads up. Nice to know you have a solid grasp on the main concepts of this community, unlike those "jizz-guzzling summerfag children" you are more mature than.

Just woke up, going to get to work. More updates later tonight.

>>251092

I dont know if you have been following the music side of this thread, but, I think everything is out of tune. 12 note equal temperament is a bad tuning system.

To my standards, when something is tuned properly in TET, its out of tune.

I agree completely. I need to tune this to very high standards of quality. Higher standards than a normal piano. I am just a bit partial when you say "it only has to be a little off." The chords ARE a little off when they are tuned to TET.


>>251093
>>251149
>>251161
>>251191

Hey could you guys cut it out? This thread is diluted enough.

>>251287
I assume the basic design for all your oscillators is the same?

All I can suggest off the cuff is for the critical components in the oscillators to have the lowest tempco that you can find for them.

If anyone was considering implementing MIDI into this project, it is not very difficult, even with basic (pun intended) programming skills and a PIC microcontroller with serial in and out

Okay!:

1. Handed off my PCB to my friend Mr. F. He said he would take a look at it and see if he could get it working.

2. Made another button. This time with lower gauge wire. MUCH EASIER to assemble. Like, a few minutes as opposed to a few hours. Definitely figured out what I was doing.
>pic related

Also I burnt out the LED again. Which sucks because now I cant test it. Dont know how I did that. I ran 3v into it from the power supply on the right leads and it just flickered on an audibly sizzled.

>>251316

Thank you, I will look into this when I start assembling them in mass.

>>251505
> I ran 3v into it from the power supply on the right leads and it just flickered on an audibly sizzled
> an audibly sizzled

Most likely explanation: you forgot the current limiting resistor or you accidentally shorted the resistor.
Assuming it was the latter: did you have the resistor in the LED's negative lead and other bare negative/grounded wires somewhere near to it?

Try covering the joints with heat shrink tubing.

>>251511

Oh that was it. I forgot the resistor.

Actually I intentionally forgot the resistor this time. I confused myself into thinking the resistor was to lower the voltage, which I couldnt mathematically justify to myself. So even then I wasnt sure what I was doing.

Okay.

Update:

So I walked into the lab today and we had a random engineer from a local semiconductor company here. He was working on his project but he over heard what I was doing with LEDs and we talked a bit.

We looked at the specs of my LEDs and found:

They are very insensitive to changes in current, meaning unless the voltage source is constant and stable the LEDs will likely destroy themselves very quickly.

It may be the case that my voltage regulars are that stable, but if they are not then I need to go back to the drawing board on my button mechanism.

Optical detectors are sold as components and I might have some luck buying those. Said engineer also showed me a small IC which can help me, but it would change the way my buttons work (perhaps in a good way).

Pic related: Its some writing we did.

>>252056
OP I have no idea what you are doing, but it looks cool as shit and very well documented. Keep it up, I can't wait to see this up and running and finally get some music made on it.

>>252061

Thanks.

I am actually getting pretty scared that I wont be able to meet my dead line, which was finish by the end of July.

I was hoping by the end of June I would have a working prototype and I could get to work on construction. The prototype aspect showed to be more difficult than I thought.

If I can get my act figured out in the next few weeks I might pull all-nighters for a week actually assembling the thing. Otherwise I think I will have to push back my deadline.

>>252056
>unless the voltage source is constant and stable the LEDs will likely destroy themselves very quickly.
that doesn't make sense, flashing led's isn't a problem and IR leds work with pulses

If the voltage isn't well regulated, It would be more of a problem for audio circuits, causing a hum (assuming it's not run by batteries)

post schematics?

>>252067

Yeah I am not sure I expressed the properly. I retyped it a few times.

I had a little schematic and math in the related image.

Basically I know the optimal amount of voltage to draw for the LED is 1.7 volts. Because at that point the current is at the marginal benefit of brightness per unit of voltage is best. That current being 20 miliamps. Any more volts and It will be wearing the LED out with little benefit in switch efficiency. Anymore current and the LED will break.

For example, if you just hook an LED up to 5 volts

(5volts - volt usage by LED) = (basically zero resistance) * Current

Current = Really big number

The current has to be very high and it burns the LED out. So since we know we want 20 miliamps and 1.7 volts we can figure out the appropriate resistance to put in series with the LED:

V = IR
(5 - 1.7) = .02 R
3.3 / .02 = 165 ohms

So as long as I have 165 ohm resistor in series all is good right?

Well not really because it assumes:

1. All my LEDs are going to behave the same way.

2. My Voltage source is constant.

Neither of which may be true.

>>252072
>So as long as I have 165 ohm resistor in series all is good right?
yea

If you're worried about it, try a 220 ohm resister and see if the brightness is acceptable. You will be <20mA at 6 volts then

are you using batteries or a regulated power supply?

>>252076

I was going to do a 9volt supply and run it to a bunch of 5volt regulators.

But I havent looked very much into the actual power supply part. I just anticipated 9 volts because I have a lot of 9 volt adapted and a lot of my music equipment is standardized on a certain size DC adapter.

I like your suggestions. I appreciate and love all my engineer friends. But sometimes their advice can be out of touch with the reality of the problem. Maybe that will work with the 220 ohm thing.

Before I go to bed I will try making up a bunch of switches and trying this out, seeing how standardized their response is (and see if I can manage to not break one).

>>252097
a single 5V regulator should work
the 7805 is rated at 1.5 amps

I am quite interested in you're project and will be monitoring this thread. thanks for keeping us updated

>>252098

Yeah I guess you are right. If I do the math I still get under 1.5 amp. The 7805 is what I have been using.

I am torn between maximizing redundancy and minimizing size.

>ran out of pics. Life Alert instead.

>>252098

the 7805 will produce up to 6w of heat dropping 4 volts, a decent heat-sink will be required.

So resident where can I find some of your music? You got a soundcloud or anything like that?

>>252134

For the last few years I have been playing the drums nearly every night. Occasionally a friend wants to jam or something, and I often play the drums to music. I would like to get back into making real music and songs and stuff, which is part of why I want to build this instrument.

Here is a video I recorded recently while I was playing the drums. This is at the tail end of like a 6 hour marathon of drumming:
http://www.youtube.com/watch?v=GtYxmp_D47g&feature=youtu.be

Here is a little song I made in Audacity a while back:
http://www.youtube.com/watch?v=fphnHWmOOVU

And then again, here is the video of me fooling around with the gamelan machine I made after I built it:
http://www.youtube.com/watch?v=Xt6GeC-08t8

Good news!

So I met up with Mr. F.

I had left the surface mount board with him and he resoldered everything. He couldnt get it working but he said:

1. At least one of my transistors was busted

2. There were a few failed connections.

We then hung around and tried to get it to work and we figured out some bizarre stuff. Namely the old surface mount oscillator on the old board that did work, was installed completely wrong. It was put together completely wrong and it still worked.

We eventually got the oscillators on the new board working.

So far this morning I have toyed around with one, making sure I can get it tuned. And I am pretty happy with my ability to tune it.

I also recorded a segement of it, if anyone wants to hear it.

I also kind of entertained myself by accidentally tuning it to exactly 3/2 higher than what I needed it to be. It was an accident, but it kind of validates some of my abnormal ideas about musical tuning: People naturally hear in terms of, and prefer whole number intervals.

>pic related is my work space. Including my computer running audacity, analog oscillator circuits, Line 6 DL4 guitar pedal, soldering iron.

>>250684
>a purely analog device will never suffer from problems like processor or hard drive failures. Even Arduino's have a limited life. Analog stuff at least feels more permanent.

yeah, about the feeling. you seem to be interpreting it as a point of pride, but it's really your own internal bs detector warning you to stop and stfu:

Arduino's have no appreciable limited life. Unless you're stressing them, i.e., operating them way out of spec for a long time. Processors don't "fail." They don't wear out, unless operated out of spec. After thousands of years, perhaps plastic coating will deteriorate, or metal will fatigue or corrode.... but do you think "analog" components will not experience the same issues? what do you think analog components are made of that digital ones are not?

Many people prefer unpredictable stuff like randomly-tuning analog circuits b/c they are addicted to surprise, as opposed to being in a situation in which they are required to reproduce a specific result. E.g. performing musicians on tour want digital equipment which will function the same every time. Analogfriends want to create a fog of quirkiness around everything they do so there will always be small changes to distract the mind. Both and analog and digital can be done well or badly.

I am all in favor of yo continuing this hard-to-watch experiment. You will learn an awful lot. But I can not let your incorrect statements remain unchallenged on the record.

>>252207

What do you think of diy electronic drums and electronic drums in general? Im interested in learning/dicking around with drums, but I don't want to bother people around me. Been thinking of getting Rock Band dum set and using drum machine, but I dont know.

>>252801

I think there is a stereotype among musicians of preferring analog stuff. Like, a guitarist buying an analog distortion pedal versus a digital one. I think this preference is largely due to ignorance. Musicians just dont understand the practical difference.I think the same goes with tube versus digital amps. The perceived difference is largely in their heads and there is often nothing wrong with digital equipment. I agree on this.

Since I recognize this trend, I dont think I have any pride or bias toward analog stuff. Digital equipment is often an advantage.

This is just my perception of music culture, and I certainly wouldnt want over step my capacity of describing that culture, so I refuse to agree or disagree regarding whether analogfags just want to be quirky.

I dont think analog equipment is made of anything significantly different than digital equipment. I have heard that arduino's have a limited life. I dont know why, this was just something I have heard from one of my knowledgeable peers.

But with that said, if a piece of analog equipment dies, I feel confident I could find and fix the problem. I am pretty ignorant regarding computerized or programmed equipment, and I do not feel confident I could fix any given problem.

So thats my bullshit.

>>252808

Electronic drums are cool. I my only experience is with the ones they have set up at guitar center. They feel nice and they work, and they are often super expensive.

Its funny you mention it because I have been thinking a lot recently about electronic drums. I kind of want to try out one of those "performance pads" or whatever, that are just a 2 by 4 grid of square drum pads.

It seems like to me, if you are going to make an electronic drum set, you should you shouldnt try and preserve how drums have been in the past. Stuff like, making electronic cymbals, or kick pedals, or arranging the pads like toms, is antiquated.

If you want to learn the drums dont use a rock band drum set. Real drums have tension and rebound, and the whole process of drumming should be mechanically efficient and rock band drum sets cant provide that.

Its happening!

So I soldered together a third oscillator on the board and the only thing that didnt work was that I had a crappy connection to one of the transistors.

At this rate I should be able to crank these out like they are nothing soon.

I am going to tune the ones I have now.

Also, I went to chanarchive.org and I noticed they dont have the old thread listed. I hope we didnt lose that forever.

>>252948
Archiving is wonky. Always save the webpage yourself. I use Firefox and merely save the images individually then click on File>Save As to save the html.

>>252948
I saved it fairly early on, up to "This is off topic, but I just finished making this bass..."

>>252981

I think that was about half way through.

Damn I wish I saved it myself.

Thanks though for saving what you did.

General wrap up of today.

I made two oscillators, one of which certainly works and the other might work. I tuned one.

I cut out a few switched. I think I am going to have to totally rework part of it. At the moment I have it to turn the LED on via the button connecting two pieces of metal. This is just really bad. For one is it adds a ton of resistance to the buttons. It works inconsistently, and I have little doubt it would fall apart in the short term.

I am going to try a new thing based off what I have observe in other consumer quality electronic organs. That being a whisker switch. A very thin wire is suspended, and the process of pushing the key pushes a wooden piece that will bump into the whisker and push it into a metal bar.

I don't know if it's been mentioned in the older threads, but you (OP) ought to get the book "The Art of Electronics" if you're at all into electronics, and it looks like you are. It is packed with theory and practical circuits, both digital and analog, has chapters on opamps, power, and tons of other goodies.
Seems like it'd be right up your alley.

>>252924
> I have heard that arduino's have a limited life. I dont know why, this was just something I have heard from one of my knowledgeable peers.

He was most likely talking about the program memory. Arduino's processor uses flash memory, just like pretty much every microcontroller nowadays. Flash memory works by trapping charges and those charges leak out eventually. Flash memory makers usually guarantee data retention of 10 years or something like that. The thing is that this value applies to the worst allowed operating conditions. In normal use (room temperature etc.) data retention is much better. This "much better" is dependent on your definition of data loss, but you can expect data retention of 100 years or even (much) more.

Funny enough, at least some Arduinos use electrolytic capacitors for power supply filtering. You can expect these "analog" things to fail much faster than the processor.

100 years is so long time that you can expect insulation to crumble, contacts to oxidize and so on. In other words, even if your stuff is fully analog, you can't really expect that it's functional after spending a century at your attic. The good thing is that you might be able to fix it.

>>252990
This might seem really stupid, but I copypastaed the entire thread when we were moving to this one - So all the pics are just thumbnails and everything's a 404d link, but I suppose it's better than nothing...

http://www.mediafire.com/?znw5llmc1b7taad

Spent today making stuff.

I made it a mission to do no quality tests. I tinned the entire PCB and made a single oscillator. Testing and fixing will come later.

Likewise I made about 6 or 7 switch housings to make changes and correct problems as I create them. I am beginning to believe I wont be able to make a successful whisker switch and that I should give up on a mechanism that turns the LED on and off. The alternative is that I just leave the LED permanently on.

I have created so many failed switch housings that I am beginning to fantasize destroying them all. Probably via burning or crushing.

>>253174

Yeah! I have a pdf of "The Art of Electronics" on my computer.

Its great. I like it better than most of the resources I have found. It also avoids math and promotes intuition. Some of my electrical friends criticize electrical engineering education for focusing on idealized and unrealistic depictions of electronics.

>>253635

THANK YOU.

I have all the images on my computer. Its a lot better than nothing!

>>253666
Any time.

Did a test on my surface mount oscillator.

It oscillated! Tonight lets see if I can put down all the components.

I soldered all the oscillators on. I happen to know that 4 of them are effectively oscillating and I have only tested 5 of the 12. The one that didnt work was missing a ground wire.

I am starting to get into an assembly line mentality. Where I will put all the transistors on all of them, as opposed to making and tuning them one at a time.

>>254931

IT HURTS TO LIVE!!!!!!!!!!!

>>254931
OP, why are you spending so much effort and time on this project, then half-assing the soldering so horribly. Solder paste is cheap and will save you time when soldering and placing these components. That board is a disaster and it's sad compared to the beauty of the rest of your project. Please OP, we love and care about you and your project.
/soldering intervention

I have the html source of the old thread here if you want it:
http://pastebay.net/1068163
it is still cached in my browser

>>255005

Is it that bad?

A lot of people have seen my project and the only people who have had problems with it are people in my thread.

Some of those oscillators were soldered on by that engineer who has been helping me, who has had a pretty long and successful career. To my understanding he is soldering on a daily basis.

I could be wrong, but I always feel like I have a good connection to the copper, I think I have only had one poor connection so far.


>>255009

Thanks!

>>255097
If it works, then it's fit for it's purpose. Fuck the haters.

>>255100

I guess...

I mean, I KNOW it works. The concern about poor connections is that they will eventually fall off, especially in response to temperature change.

But I am pretty sure I made good connections.

There's a *little* too much solder there oin those SMD components, but the joints should be fine.

I would get some adhesive so you can glue the SMD components down (they make glue just for this purpose) so they won't move when you solder them.
Then just use the thinnest solder you can find and do it sparingly.

Pic related, something I soldered just the other week with flux cored solder. (I hadn't cleaned the flux off yet).

>>255097

The first attempts were quite bad. This is much better.
There's also this thing that camera tends to be very unflattering to boards like yours, particularly in close-up shots.

>>254931
holy shit, babbys first soldering

that looks like fucking shit

Well at first glance, the soldering doesn't look great. On closer inspection... wow that shit is small. I consider myself an expert soldered and I've never attempted surface mount with an iron. I'm impressed. Carry on.... and please keep us up to date on how it's going

I don't have anything to contribute, but after seeing all the posts about saving old threads I thought I'd link this
http://archive.installgentoo.net/diy/thread/209242
The installgentoo archiver automatically saves everything on /g/, /diy/, and /sci/. If you're using 4chanX, you can even be automatically redirected there from a dead link

>>255103

>There's a *little* too much solder there oin those SMD components

Okay.

Is there anything bad about too much solder?

I have some solder wick and at first I was cleaning off all excess solder. I started noticing my peers never did this so I stopped.


>>255611

Cool! I didnt know installgentoo archived for /diy/ too.

>>255747
Not really, unless it starts bridging to other places it shouldn't. It just looks messy. Just try using the minimum amount possible to start with.

When I soldered the SMD IC in the pic I posted, I flooded the pins then sucked the excess off with a solder sucker. I hate solder wick, as you need to put too much heat into the components to make it work, and I can never get it to work properly anyway.
Solder suckers are quick, clean and easy to use.

So I need some good ideas about the switch. I am kind of stuck.

To anyone who doesnt understand how my switch mechanism works here is a description, including the related pic.

Below the button is a wooden shaft which ascends and descends with the button. On the shaft is a triangular hole cut into it. On either side of the shaft is an LED and a photo resistor. When the shaft rises and falls the resistor is exposed to more and less light, raising and lowering the volume.

The means by which I cut out these wooden pieces is not perfect, and there is ambient light. I cannot prevent all the light from touching the LED, so there will always be a little sound coming out.

One idea I have is to turn the LED on and off. But this has proven to be a mechanically challenging thing to do. I had a spring underneath the shaft the would make mechanical contact and act as a switch for the LED. It kind of works, but it looked really shoddy and I doubt it would hold up. Some of the problems I have found are:

1. Wires have physical resistance and dont like to move along with moving pieces. The button wont feel as smooth, and the wires will eventually break off

2. Two touching pieces of metal dont necessarily make electrical contact.

So any ideas on how to do this are welcome. I have really only investigated mechanical solutions regarding turning the LED on and off. There are probably other ways of doing this.

I am sure there is some electrical mechanism that can be designed that can keep the button quiet until some volume of sound has been produced. It doesnt even really need to be complicated. I know its normal to just put a capacitor to ground to get rid of background noise. I dont know why the same principal cant be used here to crush back ground sound.

>>255769

Another idea I have yet to build is to put blinds on the resistor.

I suspect that the ambient light sneaks in from the sides of the shaft, as the shaft and the hole the shaft fits into are not the exact same size. If they were the field of the button would not be smooth.

I could build blinds either around the LED or the resistor to control this light.

I want to investigate this, the problem I forsee, is that the thing is only an inch long. The shaft is 5.6 mm wide/long. Whatever blinds I make have to be really really small. I dont know if I can make anything that percise.

>>255771
>blends
First thing that came to my mind was making an aperture that opens up the more you press the switch. But that may be impractically complicated. I'll draw up a diagram in a minute.

>>255778
Like this.
Note that there will be no ambient light, since the button mechanism will only start above the light housing thing.
I assume you could make the switch that opens the blades either mechanical or electrical.
Again, apertures at that quantity will probably be expensive or complicated to make.

But maybe you find an easy/cheap way to do that.

In either case, looking into camera schematics might give you some ideas.

>>255780
Oh I just had an idea for something simpler than a diaphragm aperture.

Instead of blades, use two rings. One stationary, one moves with --

No wait. Actually, you could just use what you have with blends. I don't know why I think so complicated.
Blends on either side of the switch shaft should be enough, really.

>>255763
> I can never get it to work properly anyway.

Don't buy the cheapest wick you can find. Get one which has as fine braid as possible and decent flux. Chemtronics makes good stuff. Also, use reasonably big soldering iron tip. You can also help the wick by applying small amount of solder (helps with heat transfer).

>>255769
> 1. rigid wires

Get silicone-insulated thin wire with very fine-stranded conductor. Use strain reliefs.

> 2. bad contact

I'm not an expert on switch making, but the usual solutions seem to be wiping contacts and/or gold plating.

What comes to your LDR: put it in a short black tube. This should help with stray light, at least a little.
Assuming you can get LDRs cheaply, you could implement the on/off switch as another LED-LDR combination. Shitty pic to the rescue: the first LDR (A) is your current LDR and the second LDR (B) is a "switch" which opens the short at output when you press the shaft down. The 1M resistor at output is to prevent the other keys from shorting the output (assuming you're going to connect all the output directly together).
No idea if this is a good suggestion.

AWESOME.

You guys have great ideas!


>>255780
>>255785

I think I get what you are saying about the aperture thing. And I sort of get your simpler version.

I definitely cant do either, because the open space in the chamber is like, 15 mm by 5.6 mm. Each blade on that hatch would be like a mm wide. The laser itself takes off a third of a milimeter just in the process of cutting.

BUT, thats a really good idea about placing something in front of the shaft. What I could reshape part of my switch mechanism to have a little panel in front of the shaft hole, one which I have cut out a smaller hole in the middle.

That way I can rely on computer controlled accuracy instead of just gluing super tiny pieces of wood into place.


>>255839

GREAT IDEA.

What if instead I just ran the LED through another photo dependent resistor?

Pic related. Although I have since found that a resistor in parrallel is not feasible.

Good news everybody.

I did a test. At 5vs and 2k ohms the LED is still decently bright. I pointed it at the photo resistor and my multimeter read 2.5k ohms.

All these numbers are within reasonable parameters.

As they say at SpaceX: this is extremely nominal.

Prototyped Anon's idea.

Lets see if it works.

Thank you anon. This works well!

Here is a video of an optical switch controlling another optical switch.

http://www.youtube.com/watch?v=BH7MVzteDRU

>>255747
>Is there anything bad about too much solder?

It makes the joint weaker. The solder's surface tension fights its wetting properties and it tries to ball up while cooling. It ends up with less of a "grip" on the solder pad. Excess solder ranks right up there with inadequate heating as a cause of bad joints.

If put so much on there that you actually start bridging pads, you've gone right past "too much" and gotten balls deep into "put the fucking iron down."

>I started noticing my peers never did this so I stopped.

They likely don't put excess on in the first place. Solder wick is for correcting mistakes, and is not a normal step in creating a solder joint.

For SMD work you should be using fine pitch solder. Like 0.5mm or less.

>>255769
>I had a spring underneath the shaft the would make mechanical contact and act as a switch for the LED. It kind of works, but it looked really shoddy and I doubt it would hold up.

Most switches use leaf springs and they hold up just fine.

>Two touching pieces of metal dont necessarily make electrical contact.'

Physical contact between metals equals electrical contact. If there's no electrical contact, something is preventing them from touching. An oxide layer maybe, but it would have to be very thick and/or very strong to prevent contact under any appreciable force.

Even aluminum, which instantly forms a hard layer of alumina when exposed to air, will still conduct at the lightest touch.

Been fooling around with the oscillators.

About 2/3rds of them work I'd say.

Well that was interesting.

So I checked all the oscillators. 7 out of 11 work. And one doesnt work because it is missing a cap. Two might not work because I just didnt set the pots right.

I tooked up my double optical switch to one that did work.

It behaved in a very peculiar way. I presumed that if there resistance was high it the volume would be low. But it seemed that it works a different way. When the resistance was high the volume decreased. So I could get it in this sweet spot where it would slowly climb or descend in volume.

But, I could never get it to be immediately quiet. It would always have this kind of fade out that would last a fraction of a second. Kind of peculiar.

>>256277
Corrosion might build up faster if the metal used in the contact points are different kinds of metals. So, like metals should be recommend.

>>256845
>But, I could never get it to be immediately quiet. It would always have this kind of fade out that would last a fraction of a second. Kind of peculiar.

Do you have anything cutting off the caps when you kill the volume, or are they allowed to discharge into the circuit?

Talked to Mr. F. He seemed confident we could figure out the switch stuff.

>>256889

Uhm,

Well the oscillator is oscillating the whole time. Its just a control on the volume of the output.

Maybe I dont understand you?

Bump

Taking a little break.

Should hear back from engineer friend in a few days when he isnt busy.

bump for great justice.