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PHOBoS
Joined: Jan 14, 2010 Posts: 5591 Location: Moon Base
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Cfish
Joined: Feb 24, 2016 Posts: 477 Location: Indiana
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Grumble
Joined: Nov 23, 2015 Posts: 1294 Location: Netherlands
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Posted: Sat Feb 04, 2017 12:44 am Post subject:
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Still very impressive!
Well done |
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Cfish
Joined: Feb 24, 2016 Posts: 477 Location: Indiana
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Posted: Sat Feb 04, 2017 5:48 am Post subject:
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Thanks grumble.
Things have moved slow on the DIY front lately.
A lot of banging my head against the wall.
Might be time to see what ideas I get from those more knowledgeable than myself
My idea was to build a very simple quantizer, just a basic parallel output ADC, EZ resistor ladder with .1% resistors to take 6 accurate bits and get stepped output. A couple of opamps to adjust to simitone volt per octave output.
Seems simple.
Turns out parallel output, through hole ADCs are not common ICs anymore.
Finally found ADC0802
After fumbling through a 58 page datasheet I about 30% understand, I ordered some in.
The problem I am on now. Is that for the IC to run in a free running state. It requires pins 3 and 5 to have a quick pull low right after power up.
It seems to work when I use a manual switch to preform the function, however when I try to set up a timed one shot to preform the function, sometimes it starts, sometimes it does not.
I'm not sure if the pulse is happening too quick, if the pulse is to short or long, or if the quick reference in not quite making complete ground.
If anyone has an idea to get past this problem? I am open to suggestions. Or if anyone has an ADC that would be easier to use in a simple circuit like this?
Yes I know a micro can be programmed to do it.
That would require me to learn to program a microcontroler.
And after large amounts of money on books, a class at the local college, every micro controllers made easy tutorial I can find.
My time would be better spent genetically engineering a flying unicorn. |
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Grumble
Joined: Nov 23, 2015 Posts: 1294 Location: Netherlands
Audio files: 30
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Posted: Sat Feb 04, 2017 7:54 am Post subject:
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I suppose you use the schematics like I added to this post?
I think you could use a resistor, capacitor and two diodes that replaces the switch to have the ADC started, just like the small diagram I added to this answer.
You just have to play a little with the values.
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Grumble
Joined: Nov 23, 2015 Posts: 1294 Location: Netherlands
Audio files: 30
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Posted: Sat Feb 04, 2017 8:06 am Post subject:
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Or: you could use just use a diode that goes to the output of your mono (the Q- output I suppose...), with the cathode to the mono output and the anode to pins 3&5 of the ADC.
In this way the mono can drive the pins 3&5 to ground during the pulse and after the pulse has ended and is at logic high again, the interrupt output (pin 5 ) is able to pull Write low, and thus starts a conversion. |
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Cfish
Joined: Feb 24, 2016 Posts: 477 Location: Indiana
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Posted: Sat Feb 04, 2017 9:03 am Post subject:
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Thanks grumble
I was sure someone would have some ideas.
I was avoiding using an extra IC just for this, however I was sure I could start it consistently with a 555. Though, I had not tried that yet. |
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PHOBoS
Joined: Jan 14, 2010 Posts: 5591 Location: Moon Base
Audio files: 705
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Grumble
Joined: Nov 23, 2015 Posts: 1294 Location: Netherlands
Audio files: 30
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Posted: Sat Feb 04, 2017 12:35 pm Post subject:
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Diode D1 discharges the cap C1 if the power is turned off, so every time the power is switched on its a new start for this little circuit. |
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Cfish
Joined: Feb 24, 2016 Posts: 477 Location: Indiana
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Grumble
Joined: Nov 23, 2015 Posts: 1294 Location: Netherlands
Audio files: 30
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Posted: Sun Feb 05, 2017 2:56 pm Post subject:
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PHOBoS
Joined: Jan 14, 2010 Posts: 5591 Location: Moon Base
Audio files: 705
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Posted: Tue Feb 07, 2017 1:01 pm Post subject:
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I am not a poet either
but I shall try to rhyme
and say you did a nice job
with the NANDulator kit
hmm that didn't really work
the way that I had planned
but I am happy to hear
that it pleased the fish
oh dear, oh dear, I fucked it up
for the second time
but before this poem is over
I will make it r...ight ?!
It seems I'm getting closer
but that's still not really it
anyway nice case you build
it doesn't look like.. ehm
wait, hold on, I almost had it
I'm getting really close now
just one rhyme that's all I am asking
hey, my cat just said meow
I'm just joking 'bout the cat
I don't have room to raise a pet
except for spiders in the kitchen
and maybe some behind my bed
but I'm drifting off, it's getting silly
and that was not my plan
so let me say goodbye for now
from the moon base land _________________ "My perf, it's full of holes!"
http://phobos.000space.com/
SoundCloud BandCamp MixCloud Stickney Synthyards Captain Collider Twitch YouTube |
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Cfish
Joined: Feb 24, 2016 Posts: 477 Location: Indiana
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Posted: Sat Apr 22, 2017 9:04 am Post subject:
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I have not had much time on here lately
Now that we have 4 sets down. Going to start integrating my synth pedals.
https://youtu.be/zctUCLm9FMo
We are still a little loose. But the local crowd is loving us and we ar booking up fast |
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alanwilder81
Joined: Sep 03, 2016 Posts: 310 Location: italy
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PHOBoS
Joined: Jan 14, 2010 Posts: 5591 Location: Moon Base
Audio files: 705
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Posted: Fri Aug 04, 2017 10:20 am Post subject:
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alanwilder81 wrote: | question is about the red circled CA 3080 OTA, in the VCA section following the VCF in the signal path.
How do i go about pins 7 and 8? How does that triangle symbol translate into real world? |
The triangle would be an internal buffer. However, the CA3080 doesn't seem to have one. It actuallly looks more
like an LM13600/LM13700 but the pinout of those doesn't correspond with the circuit diagram. You are correct
that pin 6 is connected to pin 7, and then another separate wire connects to pin 8. _________________ "My perf, it's full of holes!"
http://phobos.000space.com/
SoundCloud BandCamp MixCloud Stickney Synthyards Captain Collider Twitch YouTube |
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alanwilder81
Joined: Sep 03, 2016 Posts: 310 Location: italy
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PHOBoS
Joined: Jan 14, 2010 Posts: 5591 Location: Moon Base
Audio files: 705
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alanwilder81
Joined: Sep 03, 2016 Posts: 310 Location: italy
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Posted: Fri Aug 04, 2017 3:16 pm Post subject:
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thanks Phobos
i will read that very interesting article ! |
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Grumble
Joined: Nov 23, 2015 Posts: 1294 Location: Netherlands
Audio files: 30
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alanwilder81
Joined: Sep 03, 2016 Posts: 310 Location: italy
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Posted: Sat Aug 05, 2017 8:15 am Post subject:
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Ed, precious infos. How did you find it ?
did you take a look at the Jupiter 4 manual, or you searched for the dual OTA's that were available at that time, in 1978 ?
my question is, how does the VCA NE5517 OTA differs from the CA3080 OTA used for the filter ?
does the NE5517 have a built in buffer then, just like the LM13700 ?
can the latter replace the NE5517 ? |
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Grumble
Joined: Nov 23, 2015 Posts: 1294 Location: Netherlands
Audio files: 30
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Posted: Sat Aug 05, 2017 8:21 am Post subject:
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Just googled for operational transconductance amplifier and selected pictures(?) and looked for a diagram or picture with the same pin layout.
I'm on a holiday right now (and the 3 weeks to come) and have very limited i-net if any so maybe someone else might compare datasheets for you?
Finding the right datasheet for you took me ages....
Good luck! _________________ my synth |
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alanwilder81
Joined: Sep 03, 2016 Posts: 310 Location: italy
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Grumble
Joined: Nov 23, 2015 Posts: 1294 Location: Netherlands
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Posted: Sat Aug 05, 2017 8:39 am Post subject:
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_________________ my synth |
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Cfish
Joined: Feb 24, 2016 Posts: 477 Location: Indiana
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AlanP
Joined: Mar 11, 2014 Posts: 746 Location: New Zealand
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Posted: Sun Feb 16, 2020 9:20 pm Post subject:
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Good to see you again, and I'm really diggin' the bass pedals! |
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