Soundlab Ultimate & Ultimate Expander build thread

Discussion & Documentation for Ray Wilson's synths, modules and noise boxes.

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tojpeters
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Post by tojpeters » Sat Jul 01, 2017 3:38 pm

Before you start wiring use a continuity meter and check for shorts between the power inlet pads. Check for shorts between the positive and negative pads and both of those to ground (0 volt).
I recommend #22 pre-bond wire from Smallbear.
You only need 1 color-white.
If you feel the need for colors simply take colored sharpies and run them along the length,then you can have white w/black stripe,white w/red stripe, white w/green, and even do 2 colors,white with black and red,white with black and green and so on.
Write the pot number on the back of each pot.
You need to do the on panel wiring first. I suggest the ground wire first, Notice that some places it branches in two directions adding little spurs for the LEDs and a switch.
Where the wire goes to the PCB just leave a nice long piece and trim later. Maybe put a green stripe on this one.
Mine looks a bit different than the drawing as I needed to provide 4 extra branches for the attenuvertor chicklets.
Start with a nice long piece to go from the panel to the PCB. Strip a bit of insulation,bend the exposed bit of wire and put it through the lefthand lug of pot R270 (in the lower left corner. Bend the wire around the lug making a nice connection. Solder is not glue,the wire should be attached physically. You will add 2 more wires to this lug before soldering.
Measure the length you need to get to the pot above (185) and add about an inch for stripping the ends and some slack in case of service. Attach that to pot 270 also,then measure and add a wire for pot 271. Now you can solder all three wires to the pot.
Take the wire meant for pot 185 attach it to the LH lug
Next add a small piece for the LED,maybe 1" and solder.
Now you can just move down the chain,the wire from pot 270 attaches to LH lug of 271 along with a second wire to go to pot 272,solder, and on down the line. Note there are a couple places with 3 wires.
I did the PWM knobs next. Color code the wires that go to the PCB. Note the wire that continues on to the pushbutton.
Next do the rest of the panel wiring
There are places that get a wire now and also get a wire that will run to the PCB later. Don't glob on the solder,there should be plenty of space for the second wire later.
Same general idea,you need to measure for length,including any snaking past pots and such,add a bit of slack,attach the wire well,and add the next wire in the chain if there is one and then solder. Remember you are not adding any of the wires to the PCB yet, just doing the panel wiring.
As an example a wire attaches and is soldered to the RH lug of pot 159. It snakes past a pot and a couple switches and attaches to the jack under those switches.
2 more wires attach there,one to go to the jack next to it and 1 for the center lug (RH) of switch S6. Solder the 3 wires,attach the wires to the other jack and the switch and solder.
Then push the wires down nice and tight against the panel.
Maybe while you are there do the rest of the wires associated with S5,S4,S6,and pot 253. Leave space in those pot lugs for the wires that will go to the PCB.
Do the rest of the panel wiring.
Once it is done do the cathode connections for your LEDs.
There are 2 leads coming out of your LED,the short one is the cathode.
Cut it off to about 3/8" long and bend the end over to form a little hook.
Slip a length of heat shrink onto the stub of ground wire,strip a small bit and bend a hook.
hook the cathode and wire together and crimp them together. Once again this should be a nice solid connection. Solder (not too much) let cool and slide the heat shrink tube over the joint all the way down so it is against the LED.
You can shrink it later when you do the other side.


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Last edited by tojpeters on Sun Jul 09, 2017 8:48 pm, edited 1 time in total.

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Post by tojpeters » Sat Jul 01, 2017 5:46 pm

You may want to check your wiring now before proceeding to the next phase.
You check wiring with a continuity meter,not your eyes.
Set your meter to continuity mode.
It should beep when you touch the probes together.
I'll use R186 as an example.
Put a probe on the LH lug. Now follow the chain,it should beep when you touch each connection point. Don't follow the wire,use your wiring diagram. It should beep at R191 (LH),R159 (LH),R164 and so on. Then move the probe to the RH lug. It should beep at both jacks under S4 and the RH center lug of S5. Once again don't try to follow the wire,use the diagram and your meter.

Everything good?
I mounted my PCB to the front panel with some hinged standoffs for the wiring.


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Last edited by tojpeters on Mon Jul 10, 2017 8:37 am, edited 1 time in total.

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Post by tojpeters » Sat Jul 01, 2017 6:55 pm

It's wiring time.
The way the PCB is made it makes the most sense to wire it one section or module at a time.
I suggest the following order- NOISE,MIXER,VCO-3,VC0-2,VCO-1,REPEAT GATE,AR GENERATOR,LFO 1,LFO2,VCA,VCF,S&H.
And don't forget the ground and power lines.
I realized after doing all 3 VCOs that doing the mixer and noise first makes more sense.
Print out this PCB map to help orient yourself.

http://musicfromouterspace.com/analogsy ... ulemap.gif

The following pics are of VCO 3.
Do jack connection X41 first.
With the PCB at a 90 degree angle to the panel cut a piece of wire that goes from the box marked X41 to the jack designated X41 on the wiring diagram-plus about an inch and a half,some for stripping and some for slack.
This length is dependent on your case design.
Strip both ends.
Attach the wire to the jack and solder,then put the other end through the hole in box X41 on the PCB and bend the part sticking through over to hold it in place. Flip the PCB down and solder.

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I reality I recommend putting all the wires on for one module,soldering everything at the panel side as you go but doing all the PCB side solder for each module at the same time.
Just do each jack and pot and bend the wires at the PCB to hold them in place,then fold down the PCB and solder them all.
Don't wire tie or bundle your wires,it will just make troubleshooting harder if you make a wiring error.
There is no reason to bundle them ever anyway,that only promotes crosstalk. Keeping each wire as far as possible from it's neighbors is the best strategy.
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Post by Bodo1967 » Mon Jul 03, 2017 4:02 am

The wooden front plate of my MFOS Ultimate is now blue (pics will follow). I then sawed off the too long pot shafts (which turned out to be fairly easy, since they weren't too hard).

All the pots and switches are now in the front panels, only the LEDs have yet to be inserted now:

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(The box in front contains 50 knobs).

And I've started with the wiring, but that's still in an early stage ;). I'm using the same wire I used for the MFOS Mini Synth. And yes, I also put the numbers on the pots (by and by in my case, so they're not all labeled yet).

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And I roughly designed the entire case - it will be very similar to that of my TTSH -

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- but in blue... so I can tell the two apart 8-) :mrgreen: ;) ;) ;).

@tojpeters: It really makes me happy to see you can now replace your previous MFOS Ultimate. Having a fire damage or even burn down your house is such a horrible thought :cry: .
... why buy it for $100 when you can build it yourself for $150?

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Post by tojpeters » Mon Jul 03, 2017 2:21 pm

It's alive.
I've only tested the basic functions and have not calibrated.
I don't know how to put a video here but the is a short clip on the muff wigglers Facebook page.

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Post by tojpeters » Mon Jul 03, 2017 2:27 pm


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Post by tojpeters » Sun Jul 09, 2017 1:28 pm

Finishing up

Your next step should be installing all the chips if you haven't done that,and the tempcos.
Then hook up your power lines.
I have no real advice here as you could be using any number of supplies-just make sure you don't reverse the positive and negative lines.
Hook up your main output wire from the output pot to the jack on the aux. panel. You can do the rest of the aux panel jacks once it is in the case if that is easier.
Use your meter to check for shorts between your power rails and between the rails and ground.
Moment of truth-turn on your supply.
Any pops,bangs or smoke? If not then test time.
Hook the output to your mixer/speakers.
Set your VCO frequency controls in the center.
Turn the VCA initial level all the way up,both mod controls off.
Turn the VCF cutoff frequency all the way clockwise. Resonance in the middle.Both mod pots down.
Now turn the mixer knobs up 1 at a time and you should have output- of course you need to set the levels on your outboard mixer or amp setup.
Your VCOs should respond to the frequency controls.
Try out the noise also.
Sweep the filter cutoff knob,you should hear filter sweep.
Turn all the mixer pots down and the resonance pot all the way up. The filter should self resonate and respond to the cutoff knob.

Your LFOs,repeat gate and S&H LEDs should blink and respond to knob settings. Turn down the initial gain on the VCA and see that it responds to the LFO and AR knobs-use the manual trigger button on the envelope gen to test.
You can test the S&H also.
Then test every knob to see if all work as expected.
If all is good next is calibration. Feel free to play with it a while before calibration.
If you need to do troubleshooting don't panic.
There is a troubleshooting guide on the MFOS website.
Last edited by tojpeters on Sun Jul 09, 2017 8:54 pm, edited 2 times in total.

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Post by tojpeters » Sun Jul 09, 2017 2:44 pm

Calibration
You should read the calibration section of the MFOS site.
I use a 4 octave midi controller plugged into a midi to cv converter.
Set any octave switches on your keyboard to make your low C put out 0 volts.
Use your meter to set all three high freq trimmers to max resistance between poles 2 and three.
Set your fine tune controls to the center.
Choose a VCO to do first,I started with #3.
Connect the output of your midi to cv to the log cv input.
Set your meter to measure frequency (Hz) and hook it up to the switch that selects which wave shape goes to the mixer, any pole will do.
Press the low C key and use the coarse then fine tune knobs to set the frequency to 100Hz.
As you press each C key going up through the octaves you want to see a doubling of the frequency with each octave you go up-100Hz,200Hz,400Hz,and 800Hz.
These will not be exact yet but should be in the neighborhood.
So you have 100Hz with the low C key,press the C key 4 octaves up and see what you have. You are looking for 800Hz.
If the frequency is too low turn your scale trimmer a couple turns in the direction that makes it go even lower,
If high make go even higher. If you are reading 820Hz I'd turn the trimmer until it is reading 830 or so.
now press the low C again. You will need to readjust your frequency knob back to 100Hz.
Now press the high C key again (4 octaves up) and see what you have .Once again turn the trimmer to send the frequency higher if it too high or lower if to low.
Go back to low C,adjust the freq. pot to 100 Hz again then go up 4 octaves and see what you have.
Once you get the reading fairly close start with the high frequency trimmers. These trimmers interact. Go up 2 more octave from the high (800Hz) C key. You want 3200Hz here.
It will probably be quite low,like 3150 or so.
The High freq. trimmer should be bottomed out in one direction,turn it the other direction until you raise the frequency to 3220 or so. It takes quite a few turns.
Now go back to low C,set freq pot to 100Hz, up 4 octaves and adjust towards 800Hz,once again trimming it higher if it too high,lower if it is too low. But instead of going back to low C go up 2 octaves and set the high C to a little above 3200 Hz.
Then back to low C , set to 100Hz,check 4 octaves up and adjust the same way as before honing in on 800Hz,then up 2 octaves and set the high freq. trimmer to 3200 Hz.
You should be quite close now.
Keep repeating until it is good.
You may not end up with exact numbers, 100 ,200.1 ,399.8. 800, 1597, 3202 might be your final results and the the discrepancy is probably more due to inaccuracies in your midi to cv unit rather than the VCOs.

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Post by tojpeters » Sun Jul 09, 2017 3:36 pm

The VCF calibration is essentially the same. If you added the high frequency compensation trimmer mod as outlined on the MFOS site it is the same.
If not I'd use the same procedure as for the VCOs but start at 200Hz and go up 2 octaves from there. Once you get 200Hz-800Hz right you can try to extend that a bit if you care to. 2 octaves is good enough for me.
The VCA has 2 trimmers,one of which you need an oscilloscope to set.
Likewise the noise has a trimmer you need a scope to set.
An older used scope should set you back less than $100 even with shipping.
Try to find one with probes included.
The next steps are installing it into your case and hooking up the aux panel plus any mods you have done. I don't wire up any of the mods until it is all working,no sense in more stuff in the way in case of troubleshooting.
But you are done with the hard stuff.

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Post by tojpeters » Tue Jul 11, 2017 12:47 pm

The build of the Ultimate expander is the same as the Ultimate. Stuff and solder the board following the same procedure as outlined for the Ultimate.
The wiring is the same also,but there are a few places where you need to use shielded cable or a twisted pair. I prefer twisted pair as shielded cable can be fragile and too easy to break off at the solder joints.
The inputs to the mixer and the external signal booster are the places where you need some sort of shield.
You can tell where Ray has shielded/twisted cable in mind as there is a seperate pad for the ground.
There will be a lot of pads not used when you finish the main panel wiring as there are quite a few connections to the aux panel. Probably wait until the aux panel is in the case for wiring.

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Post by tojpeters » Tue Jul 11, 2017 1:18 pm

Next up is building your case.
I'm doing mine in a slightly oddball fashion so it will be the right size to put Serge panels over or under it.
Basically I'm turning it into one giant front panel with a dimension of 35"x10".
My layout includes room for a panel for the mods and some future expansion space.
I'm building mine out of 1/2" MDF because I have most of a sheet on hand from another project.
Plywood is a viable choice,cabinet grade is even better.
Pine boards work well or even a nice hardwood if you have the money.
Stain or paint might be nice. It just depends on how much time,effort,and money you want to put into this project.

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Post by Bodo1967 » Fri Jul 14, 2017 2:03 am

On the last few days, I continued with the panel wiring. It is by far not finished, but there is some progress:

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That's of course only the first panel. One more "big" and three small panels (the two aux panels plus my socket adapter) to go once this one is ready.

The case is mostly built by now. Did I say its shape is gonna be similar to that of the TTSH 8-) ?

Well, that's how it looks now:

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The case itself is high quality birch plywood, which we call 'multiplex' in Germany. However, since you can see the "stripes" on the edges I glued birch veneer on them so it'll look like "one piece wood". The tape on this picture is holding the last veneer stripes in place while the glue sets. Of course there are strips of wood between veneer and tape so the pressure will be more or less equally distributed.
... why buy it for $100 when you can build it yourself for $150?

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Post by tojpeters » Sat Jul 15, 2017 2:03 pm

A few notes about the Aux panels.
The ultimate auxiliary panel has 3 additional log cv inputs for the VCOs. I used twisted pair with one leg grounded for these so the don't pick up stray voltages and cause the VCOs to drift up and down. Really it would be a good idea to use switched jacks here normalled to ground to keep them quiet when not being used. The external signal input should also be a twisted or shielded wire to keep noise out of the mixer.
The aux panel for the expander has several places needing shielded wire. Any place where there is an additional ground pad next to the wire pad needs a twisted or shielded wire.

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Post by tojpeters » Thu Jul 20, 2017 1:31 pm

Use the same procedures for testing and calibrating your Expander. The VCF has a high frequency trimmer so use the same procedure as for the VCOs,
Maybe try to get 200-1600Hz. I would expect 4-5 octaves of good tuning.

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Post by tojpeters » Thu Jul 20, 2017 2:03 pm

If you are doing any of the mods for the Ultimate listed on the MFOS site wait until everything is tested before you start in case of troubleshooting.
I added all the mods.
I have 2 high gain mixer inputs with attenuators plus 1 input at the same gain as the rest of the mixer, and of course the MIX OUT mod you need for the expander.
I internally wired the mix out jack to the mix in jack on the expander aux panel normalled to a switched jack. You can still use the mix out jack and you can feed some other external signal into the mix in buffer if you want.
I added a extra CV input to the filter with an attenuvertor,2 signal inputs (one with an attenuator),and a signal out.
For the VCA I added a CV in with attenuvertor,a signal in with attenuator,a signal out and an offset.

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Post by tojpeters » Thu Jul 20, 2017 2:49 pm

Here is a way to make a panel for the mods.
Decide what size works for you.
You may want to stick with a common size and order more than 1 piece of metal as the price drops a lot when you get 10 at once.
In the USA you can get precut aluminum from metal supermarkets
You need to design your panel artwork and print out one copy in high quality plus a couple more in wire mode with cross hairs for your drill points. You need the center of the hole defined along with the edge.
Tape or glue with rubber cement a copy with the drill marks onto your metal.

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Mark your drill points with a spring loaded punch.
Then I use a small drill bit in a nut driver to make the marks more distinct.
You can use a center punch and hammer but that many hammer blows will curve the metal significantly and you will need to peen the back side.

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Next drill out your hole with a step drill (use a drill press if you have one)
Now here is the big secret to a nice looking paper face panel- watch your drill bit. Drills wander and even with a perfectly centered start it will probably start to drift towards one edge of the hole. Just watch your bit at each step and stop drilling when the hole gets to the circle that defines where the hole is supposed to be.
After all the holes are drilled you use a file to enlarge the holes right up to the edge of the line.
You may need to use a second printout if the first is too rough after the drilling,or even glue the finished print down and use that as your file guide. Just keep your hands clean so you don't smudge the final print.

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Next tape you finished print to a well lit window facing away from you.
Coat the metal with contact cement and press in onto the paper using the light coming through the holes and around the edge to line it up.
Remove the paper from the window,place it on a sheet of scrap paper face up,put a cover sheet on it and roll it with a rolling pin or something to get a good bond.

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Trim with a razor blade.
Now install the jacks and pots.

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Post by tojpeters » Fri Jul 21, 2017 5:15 pm

Each of the places you attach the mods wires to is well documented on the MFOS site.
Just do it like the directions say.
For each module section you mod you need a small piece of perfboard to mount your resistors (and caps on some inputs)
Build a little board,keep the attachment points as close as possible to the pcb and run long wires out to the mods panel.
Here is an example of how I wired my extra mixer inputs and output.

Image

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Post by tojpeters » Fri Jul 28, 2017 1:57 pm

It's mostly finished, I'm missing a couple capacitors for the mods and 1 chip in the filter in the ultimate.
I'm pleased with it,it is just the way I remembered.

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Post by Bodo1967 » Mon Jul 31, 2017 2:29 am

tojpeters wrote:It's mostly finished
[...]
I'm pleased with it,it is just the way I remembered.
Awesome, and as I said before, I'm so happy for you that you can/could replace your old one.

Panel wiring on mine is now complete except for the Expander Aux Panel, and the case is completely finished except for the back (needs a hole for the cable, and some paint, but is also finished otherwise). I'll post some pics soon, hopefully somewhen this week :).
... why buy it for $100 when you can build it yourself for $150?

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Post by Bodo1967 » Mon Aug 07, 2017 1:57 am

This is how the PCBs will be placed in the case (mounting holes are already drilled :)):

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[x] All panel wiring is done.

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And now it was time to assemble case and front plate. This is how the instrument actually looks like - except for the knobs, that is.

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Time for the last finishing touches on the PCBs - i.e., add the tempcos and put the ICs in their sockets.

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I tilted the case by about 20 degrees (in other words, leaned it against a shelf behind/above the workbench for better access :party: ). This can't really be seen on the pic, but it helped a lot. About 70 % of the Expander connections are now done - I did this first, since I work (mainly at least) right-handed, and starting with the Expander allows me to work "from left to right", which is more convenient for me without getting the Ultimate wires in the way.

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Can't wait to get it running :D.
... why buy it for $100 when you can build it yourself for $150?

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Post by Bodo1967 » Fri Aug 18, 2017 1:04 pm

Yayyy, I finished the wiring part today.

That's how it looks now:

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The back panel (6 mm birch plywood painted black) is also ready, so what I need to do is:

* clean out the inside (bits of wire insulation and such);
* mount the PCBs and connect the mains cord;
* test, calibrate and, if required, troubleshoot;
* put the back panel on;
* add the knobs;
* PLAY :nana:
... why buy it for $100 when you can build it yourself for $150?

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Post by synthcube » Fri Aug 18, 2017 1:09 pm

fantastic!

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Post by Bodo1967 » Mon Aug 21, 2017 3:14 pm

I started testing the synth yesterday, so here's the first o-scope pics:

According to Rays's instructions, the repeat gate generator is supposed to produce a pseudo triangle wave on IC 21 pin 2.

That's how it looks (low repeat rate):

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(The 'double lines' are due to the long exposure time - 0.6 seconds: The signal starts in the bottom right, then goes through the entire display from left to right, and then starts from the left again. So you can just ignore these double lines.)

Higher repeat rate:
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Pin 3 should show a square wave. And it does (of course also responds to rate setting).

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I then checked both LFOs (pictures are of LFO 1, but both behave absolutely identically).

Square wave, 2 rates:

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Triangle:

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Rising and falling sawtooth:

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High/low range, frequency adjustment, and all waveforms work fine on both LFOs :nana: .

Sample and hold rate as observed on C64 (high rate):

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And at a low rate.

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Again, the signal begins on the bottom right, exits the display, comes back on the left side - and in the middle, the shutter of my DSLR closed, so it's not fully shown. This is in the second range, so I had a 'moving light point' on my scope, of which the pic shows the trace. You can easily imagine the 'pseudo sawtooth wave' Ray describes on the pic, and that was indeed how the light point moved on the display, and very nicely at that. Exposure time is 1/3 sec this time. Free handed, holding the camera in my right hand and the 'scope probe in the other :D.

And finally, S&H applied to a LFO triangle wave looks like this:

Image

That's it for now, more to come soon.

* clean out the inside (bits of wire insulation and such)
[=> done]

* mount the PCBs and connect the mains cord;
[=> mains cord of course connected for testing, but without the back panel]

* test, calibrate and, if required, troubleshoot;
[=> in progress]

* put the back panel on;
[=> last step to do when everything else is done]

* add the knobs
[=> done]
... why buy it for $100 when you can build it yourself for $150?

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Post by Bodo1967 » Thu Aug 24, 2017 2:14 am

I continued testing yesterday, so here's some more o-scope pics :hihi: . Concerning "double lines", please refer to my previous post.

Again, I strictly followed Ray's troubleshooting instructions.

The first module up yesterday was the AREG in trigger mode and with range set to "short", triggered by the RGG:

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Switched to gate mode:

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Trigger mode again, but range set to "long" this time - one can easily see the slope change, and the now missing "gaps" between the envelope curves.

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And switched to gate mode once more:

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Manual gate (triggered by the pushbutton) as well as the attack and release time controls also work nicely. Check mark on the AREG :D.

Next up was the white noise generator. Well yes, that's how white noise looks on the o-scope :tu: :

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I then briefly tested the function of the VCOs (sawtooth and square wave shape, PWM, response to frequency control). Everything works absolutely flawlessly in VCOs 1 and 2, but VCO3 apparently requires some troubleshooting. All I got was like a "band" signal :despair: . However, the cause hopefully will be relatively easy to find since all the VCOs are perfectly equal so I can directly compare all respective points in the circuit.

I haven't calibrated them yet since I want to have more time than I had yesterday to do it properly.

Anyway, I then continued with the VCF.

Crank up the resonance until the filter self-oscillates and produces a nice sine wave:

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It flawlessly responds to changes in the initial cutoff frequency setting. Just as it should :).

I then checked if it indeed does do its job - and yes, it does.

First I set the initial cutoff to about 2/3, as suggested by Ray, and fed it a square wave from VCO 1:

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Resonance somewhat higher:

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And with high resonance, just before the filter starts to self-oscillate:

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The same procedure with a sawtooth signal, also from VCO 1:

No resonance:

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Moderate resonance:

Image

And, finally, high resonance just before filter self-oscillation:

Image

And that's it for today :D.
... why buy it for $100 when you can build it yourself for $150?

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Bodo1967
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Post by Bodo1967 » Sat Aug 26, 2017 11:22 am

Bodo1967 wrote:I then briefly tested the function of the VCOs (sawtooth and square wave shape, PWM, response to frequency control). Everything works absolutely flawlessly in VCOs 1 and 2, but VCO3 apparently requires some troubleshooting. All I got was like a "band" signal :despair: . However, the cause hopefully will be relatively easy to find since all the VCOs are perfectly equal so I can directly compare all respective points in the circuit.
Trouble shot :banana: . After having suspected the MPF102, it turned out that the SSM2210 (see early up on page 1 of this thread for pictures) of VCO3 was faulty: Took it out, inserted 2 out-of-the-box (i.e. non-matched, but that's OK for a quick does-it-work-or-not test) 2N3904 instead, and *bingo*: A nice sawtooth just as it's supposed to look :tu: .

Luckily, I had bought one more of the SSM2210 than I needed so I had a spare. Soldered it on the small adapter pcb, inserted it into the IC socket, et voilà: Works.

Image Image Image

So calibrating all three VCOs is up next :D.
... why buy it for $100 when you can build it yourself for $150?

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