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dirtyworm
Joined: Jun 22, 2011 Posts: 20 Location: new york
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Posted: Sun Oct 07, 2012 10:01 pm Post subject:
first attempts at oscillators 40106 & 4093 |
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I’ve been lurking for a long time now and finally am trying to actually make something beyond distortion pedals. I don’t have much experience; most of my schematics are hand drawn. I have bread boarded 2 oscillator circuits for the first lunette I ‘m working on. I hoping that any errors or improvements can be made on the bread board prior to soldering.
These 2 circuits are a mash up of some of the things I’ve seen about the forum and elsewhere. I've tried to add an additional triangle out but haven't had any successes yet.
CD40106
[img]http://www.flickr.com/photos/60600641@N04/8065701550/[/img]
CD4093
[img]http://www.flickr.com/photos/60600641@N04/8065701584/[/img]
cannot see pic have to look into that... |
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Psyingo
Joined: Jun 11, 2009 Posts: 248 Location: Canada
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Posted: Sun Oct 07, 2012 10:06 pm Post subject:
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dirtyworm
Joined: Jun 22, 2011 Posts: 20 Location: new york
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Posted: Sun Oct 07, 2012 10:08 pm Post subject:
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thanks.
basic osc with mod inputs for freq, gate with trans, and width type thing from Bugbrands osc. |
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Psyingo
Joined: Jun 11, 2009 Posts: 248 Location: Canada
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Posted: Sun Oct 07, 2012 10:11 pm Post subject:
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on the 40106 schematic... pin 1 of IC1A is tied to ground... and the caps go to ground... im not sure thats what you had intended when you drew it.
also, these schematics are kinda hard for me to understand, just the way the grounds are referenced. i've seen that before... but not quite like that.
and apparently S3 switches between ground and... ground? |
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dirtyworm
Joined: Jun 22, 2011 Posts: 20 Location: new york
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Posted: Sun Oct 07, 2012 10:17 pm Post subject:
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Yes, I had a hard time trying to make it clear. I'll have to clean it up for future ref to trouble shoot.
Ground wire was not deleted. Just the caps go to ground. I'll have to get that.
S2 & S3 is connected to ground by pin 1 and pin 3 go to IC1A pin 1 but that is incorrect now that I see it, it should go after the resistor to the pot. |
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dirtyworm
Joined: Jun 22, 2011 Posts: 20 Location: new york
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dirtyworm
Joined: Jun 22, 2011 Posts: 20 Location: new york
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dirtyworm
Joined: Jun 22, 2011 Posts: 20 Location: new york
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bubzy
Joined: Oct 27, 2010 Posts: 594 Location: United Kingdom
Audio files: 64
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Posted: Sat Oct 13, 2012 12:54 am Post subject:
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its quite common for LFO's to affect other circuits,
im not an expert on CMOS but i think that if you are building 2 oscillators on the same 40106 that you are almost guaranteed to have some form of interference. so heres a couple of things to try.
1. use seperate chips for seperate functions (this does kinda waste the 5 other oscillator possibilities on the 40106)
2. use a decoupling capacitor, this is a relatively low value(100nf) cap that goes between your +v rail and GND, you can think of it as a "backup power source" that the chip can draw from if the psu is struggling
3. check the output of your PSU and make sure that your circuit is not drawing more current than it can supply, this is quite common and interference is often the effect of starving. although almost all psu's can deliver enough to supply a couple of cmos chips.
additionally, is there any reason you are running at 5v? most cmos chips will run happily up to 15v, this *might* give you a result.
again, im no expert, just a fiddler. some boffin will correct me soon enough _________________ _Richard_ |
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analog_backlash
Joined: Sep 04, 2012 Posts: 393 Location: Aldershot, UK
Audio files: 21
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Psyingo
Joined: Jun 11, 2009 Posts: 248 Location: Canada
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Posted: Sat Oct 13, 2012 5:29 am Post subject:
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Are you decoupling your power supply? Some big caps, say above 100 uf and 100nf on the power pin of every chip? Decoupling if extremely important. |
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dirtyworm
Joined: Jun 22, 2011 Posts: 20 Location: new york
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Posted: Sat Oct 13, 2012 5:41 am Post subject:
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Thanks.
I suspected that running several circuits on the chip might be part of the problem. I listened to my WSG to hear if I had the same problem, I didn’t seem to hear it which is why I was suspecting my breadboard or the LED with the trans. I’ll make 2 osc on different chips and see what happens.
As far as 5V there is a reason, although I am thinking of making it 12v via a regulator, I was having a problem with the CD4070’s at 9v, battery power with no regulator; after I changed it to 5v the 4070’s worked great so I just kept it.
Analog_backlash I tried that and it reduced the affect tremendously. I have to try it the way you have it set up, I kept the LED going to +V after I post this I set it up like you have it see what the difference is.
Edit: OK different boards, separate chips. I can still hear a hint of the LFO. Seems to work out fine. |
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dirtyworm
Joined: Jun 22, 2011 Posts: 20 Location: new york
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Posted: Sat Oct 13, 2012 6:19 am Post subject:
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Psyingo wrote: | Are you decoupling your power supply? Some big caps, say above 100 uf and 100nf on the power pin of every chip? Decoupling if extremely important. |
Yes. I am using a 100uF electro cap. Pin 7 is to ground. Pin 14 to +V and pos lead of cap, the neg lead to ground.
I’ve also tried placing the negative lead to pin 7 and ground.
Edit: I don’t know if this would make a difference, but I added an additional 100uF cap and 470nF cap right after the regulator, I say additional because I already have 100uF caps on each chip. It seems to have improved it even when I run the circuits on the same chip. |
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analog_backlash
Joined: Sep 04, 2012 Posts: 393 Location: Aldershot, UK
Audio files: 21
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Posted: Sat Oct 13, 2012 8:13 am Post subject:
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I'm glad that it has improved things dirtyworm. I thought that it might help. |
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dirtyworm
Joined: Jun 22, 2011 Posts: 20 Location: new york
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dirtyworm
Joined: Jun 22, 2011 Posts: 20 Location: new york
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dirtyworm
Joined: Jun 22, 2011 Posts: 20 Location: new york
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trav
Joined: Sep 11, 2012 Posts: 108 Location: Auckland
Audio files: 16
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Posted: Mon Oct 15, 2012 3:00 pm Post subject:
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this isn't as important as the grounding of unused gates issue in the 5-note lunetta thread, where both inputs and outputs were grounded: here you've correctly grounded only the inputs (pins 11 and 13), but there's no need to waste a 100k resistor on each; unused cmos inputs can be tied directly to ground. The only inputs you want to tie to ground thru a pulldown resistor are ones that are sometimes hanging, usually thru a jack being unplugged. When you unplug a signal from the input the gate then gets a steady LOW signal thru the resistor to ground. Plug something in again and you'll get whatever signal is coming thru the jack.
That said, I haven't had any issues leaving whole gates hanging in chips like the 40106, using only as many as I need. Maybe someone can tell me whether there is any problem in this approach. Is it necessary to ground all unused inputs even where there are multiple separate gates within a chip?
edit: sorry for being slightly off-topic, dirtyworm. it looks like a fun oscillator thing you've made. sounds? |
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dirtyworm
Joined: Jun 22, 2011 Posts: 20 Location: new york
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Posted: Mon Oct 15, 2012 9:07 pm Post subject:
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Right there is no need for the 100K resistor on the unused inputs it just needs to be tied to ground or depending on IC to the +V. I’m remembering it being said here on the forum somewhere, the 100k is for impedance purposes for when the something is being plugged in and out. The unused input are being used now I taken 2 of the outputs and run them to the input which gives me the inversion of the other. Just another option and I can use the whole IC that way.
However, there are problems. playing with it tonight I realized that the touch control, on one board and the osc on another, changes the pitch even when its not connected to any of the inputs of the osc, its interfering somehow. different boards and IC’s with their own caps to reservoir power both the IC pin 7 &14 and the whole board, not sure that means anything though.
There is some fundamental I’m missing here, I know that I am inexperienced and do not know much about electronics. I plan on making all of this modular, so each with have it own board and a connection to the power. I planned on send the 5V from the regulator out to all the boards. How do I minimize such interference between circuits on each board? |
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dirtyworm
Joined: Jun 22, 2011 Posts: 20 Location: new york
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dirtyworm
Joined: Jun 22, 2011 Posts: 20 Location: new york
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Posted: Fri Oct 19, 2012 9:23 pm Post subject:
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Having a bit of trouble with building a sequencer for the oscillators I have, I start with the baby 10 thinking that is simplest place to start. The sequencer that I current have working, only in 4 steps, I’m attaching below perhaps others will have a better way to accomplish this.
The problem that I am having is getting the gate to work at one output. I eventually have what I am using through trial and error, no theory at all. I made an AND gate at the end just to give it that punctuation on each gate from the 4017. I would like to change that out to a CD4081 but I’ll have to order it, but I’ll wait until I see if there is a better solution. I was only able to get the sequencer to work with NAND logic sent into the input of the 40106. This is what I have my oscillators using as a gate anyway, but I’m unsure if it will work with anything else, as I don’t have anything else at this time.
I’ve tried several schematics I found online but none of them seem to really do it, individual gate will work fine but a linear sequence no, most likely due to the way I have the oscillators set up, and the ones that I’m sure would work are more complicated then I want for this, I want to keep it as simple as I can.
I didn’t tie the pots to ground as I didn’t like the way that work for my oscillators but I have to try it again seeing that is how most schematics seem to do it.
I still have to figure out how to get LED’s in there but my breadboards have no room left.
since it is working with the osc that I have I'm thinking maybe I just keep it, and change the AND gates to the 4081 or at least see if they make it easier when I have to actually solder this up...
Im still running at 5V so I don't know if it will work at at 9v or more.
being a noob is fustrating...
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elmegil
Joined: Mar 20, 2012 Posts: 2177 Location: Chicago
Audio files: 16
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dirtyworm
Joined: Jun 22, 2011 Posts: 20 Location: new york
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Posted: Sat Oct 20, 2012 7:38 am Post subject:
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The far top right is the oscillator itself that I was testing everything on. The dotted line is just there to point to which input and outputs I was connectinh them to. After the 4017 there are three paths that break off to folded, the top is to modulate freq, the right is all 8 gates to a single output, the bottom to output single steps. At the end of each gate the is an AND logic with incoming signal from the path and the clock input. The pull down resistors are the only way I could get it to work without the LED's...no theory just trying stuff till it worked, I'm sure there is a better way to do it. Just having the OR logic with AND at the end didn't work for me. |
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elmegil
Joined: Mar 20, 2012 Posts: 2177 Location: Chicago
Audio files: 16
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Posted: Sat Oct 20, 2012 8:42 am Post subject:
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You can think about current like water. That single diode offers a lot less resistance to the flow, so most of the current is going to go that way, and almost none will go through the one with the two resistors attached. |
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dirtyworm
Joined: Jun 22, 2011 Posts: 20 Location: new york
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Posted: Sat Oct 20, 2012 9:13 am Post subject:
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I wasn't thinking that a pull down to ground with a resistor after it was the same as two resistors in series.
I'll re-draw only a portion of it tonight to just test one part of it. |
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