[IN STOCK] DTM: Moog CP3-type discrete mixer PCB, Euro panel

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raccoonboy
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Post by raccoonboy » Thu Apr 11, 2019 4:47 am

Agawell wrote:1N4001 is a diode, for both this and the ferrite beads go to the actual product page that's missing and there should be a show similar button - compare the datasheets - if they match you are good to go

if they don't try to find the closest and check back here

quick hint on searching - only search on the last bit of the code - the first part is a mouser category code

I found quite a few variations of "1n4001"
thanks a lot

Very helpful.

Okay.

I found this:
https://eu.mouser.com/ProductDetail/Vis ... LcIiFLn0zf

and

the closest match I could find for the ferrite beads is the following.

Impedance not listed though :\ but it is in the data sheet with some graphs I don't understand. but similar values and size and it is also 'radial mounting', but it's 2mm bigger? Not sure how much this matters though it might be better than slightly smaller.

https://eu.mouser.com/ProductDetail/Mur ... uUMCjnI%3D

what do you think?

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Post by Agawell » Thu Apr 11, 2019 4:57 am

I think that if the figures match in the datasheet and the part fits in the pcb - then everything should be ok!!

generally things like max voltage are not massively important - just make sure you get at least the stated value

I'm at work if you can hold off ordering for a while I can take a look at the BOM - I'm thinking of building one of these soon
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Post by mgallagher641 » Fri Apr 12, 2019 2:57 pm

Hi folks,

I just built one of these - the 12v version for Eurorack - using a PCB, panel, pots and knobs ordered from Thonk, and the remaining parts from Mouser. A very straightforward and easy build, and it seems to be working great. Sounds awesome, and only 4hp.

The most laborious part was identifying all the parts on Mouser. Things like the 10 pin header, I literally spent about 30 mins sifting through a million different items before locating the correct one.

So to save some work, the following link should take you to my Mouser project page with all the required components and quantities:

https://www.mouser.co.uk/ProjectManager ... 9758aa1fa0

These parts all seem to work and are the correct dimensions for the PCB.

In case the link dies or doesn't work, I also have an excel spreadsheet that I am attaching. This was downloaded from Mouser with all the part numbers, so should be easy to import into your own Mouser account. Under the BOM tab in Mouser there is an option to import a spreadsheet.

A few notes, with apologies if any of this is stating the obvious:

- My Mouser project doesn't include the pots or knobs as I got these from Thonk. So you may need to add these in. Be sure to get the right pots, as they solder to the PCB, so need to have the correct spacing of the legs.

- I ordered 4 of each of the NPN and PNP transistors and then used the HFE feature on my multimeter to choose the closest matched two of each. If you're not fussed about matched pairs, you'll only need 2 of each.

- I chose audio grade electrolytic capacitors. Who knows if this makes any difference, but I thought I might as well spend a few more pence. If you're desperate to save a tiny amount of money, cheaper options are available.

- The BOM lists various possible values for the electrolytics. I used 10uf for all three.

- For soldering the sockets, you have to make sure you are using the correct lugs. I looked at the photos of what others have done.

- Cost: while the parts came to only about £13 or so, shipping from Mouser was nearly as much again, and then with VAT the Mouser order was £31. The PCB and parts from Thonk were about £30. So all in this cost about £60. I've seen this module sold second hand for less than that. I am just getting into DIY modules and really enjoying it, so it made sense for me. I believe Mouser orders over £33 qualify for free shipping, so it would make sense to lump multiple builds together. I looked at Rapid, Farnell etc but Mouser was by far the best in terms of having everything required and being able to order small quantities.

- Finally, I was a bit shocked by how much plastic packaging came with the Mouser order. Several things were double or even triple bagged. It seemed excessive, and that plus the shipping made me think about the environmental impacts. I'm old enough to remember the days when you would just go down to your local electronics shop and they would put everything you wanted in a paper bag. That's long gone - now it's all coming from one insanely massive warehouse in Texas.

Anyway - big thanks to negativspace for putting this project out there, and to Thonk for the PCB and panel kit.
Attachments
Mouser Manhattan DTM minus pots and knobs.xls
(23.5 KiB) Downloaded 13 times

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defalut
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Calibration woes

Post by defalut » Wed Apr 24, 2019 8:30 am

Sorry, a noob question again, unfortunately search is still not working so i gotta ask anyway.

I read the first post in the thread, got to the right amount when i calibrated the LM337 and measured up -6.0V.

But when i try the last one:

"3) Adjust the 100R trimpot until the output has no DC offset with the output knob at 12:00."

How do i do that? Do i plug a cable in the out port and measure in it´s end, set the out pot to dead center and fiddle with the trim pot?
Tried it, does not work. I can never get to the right amount, the trim pot starts clicking and then i´m at -080mV or something

What and how do i measure? :hmm:
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Post by Rex Coil 7 » Wed Apr 24, 2019 10:48 am

mgallagher641 wrote:Hi folks,

I just built one of these - the 12v version for Eurorack - using a PCB, panel, pots and knobs ordered from Thonk, and the remaining parts from Mouser. A very straightforward and easy build, and it seems to be working great. Sounds awesome, and only 4hp.

The most laborious part was identifying all the parts on Mouser.....

- Finally, I was a bit shocked by how much plastic packaging came with the Mouser order. Several things were double or even triple bagged. It seemed excessive, and that plus the shipping made me think about the environmental impacts. I'm old enough to remember the days when you would just go down to your local electronics shop and they would put everything you wanted in a paper bag. That's long gone - now it's all coming from one insanely massive warehouse in Texas.
I hear you. Some states (maybe just one) have made making plastic drinking straws a misdemeanor level crime ... and yet my Mouser order shows up with enough parts to fill your palm yet wrapped in plastic mummification that many cities won't take as recycling. Seems our focus is always in the wrong place, in some states more than others. More worried about drinking straws (most of which originate from South East Asian countries that don't abide by Earth friendly policies) than the used hypo-needles and human feces on the sidewalks left by scads of the homeless.

Woops, there goes another Mouser package in the trash! :picard:
mgallagher641 wrote:Anyway - big thanks to negativspace for putting this project out there, and to Thonk for the PCB and panel kit.
Totally agree! Excellent project, easily built, and sounds tits!

:agree: :agree: :agree:
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Post by soup » Wed Apr 24, 2019 12:17 pm

I built one of these the other day...
Image
Image
:tu:

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degeneratedsines
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Post by degeneratedsines » Wed Apr 24, 2019 1:10 pm

@soup it looks awsome!

@defalut yes pretty much. don't forget to attach/touch the black probe of your multimeter to ground during the measure.

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Re: Calibration woes

Post by mgallagher641 » Sat Apr 27, 2019 8:51 pm

defalut wrote:Sorry, a noob question again, unfortunately search is still not working so i gotta ask anyway.

I read the first post in the thread, got to the right amount when i calibrated the LM337 and measured up -6.0V.

But when i try the last one:

"3) Adjust the 100R trimpot until the output has no DC offset with the output knob at 12:00."

How do i do that? Do i plug a cable in the out port and measure in it´s end, set the out pot to dead center and fiddle with the trim pot?
Tried it, does not work. I can never get to the right amount, the trim pot starts clicking and then i´m at -080mV or something

What and how do i measure? :hmm:
You can do it that way, or you can just do this by measuring the voltage between the two pins of the output socket, to which you have soldered wires. You're looking for zero volts with the knob at 12.

To be honest, I suspect this isn't completely critical. That bottom knob is an attenuverter for the main output, so for normal audio use I have mine set at max +ve and leave it there. Getting the zero volts at 12 o'clock correct just means that the mixer will go to zero at that point. Unless getting precisely to zero is super critical for your application, e.g. for processing CVs, getting it to within 80mv should be fine, I would guess - although if someone wiser than me knows any different then please correct me!

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Re: Calibration woes

Post by defalut » Mon Apr 29, 2019 3:14 pm

degeneratedsines wrote:@defalut yes pretty much. don't forget to attach/touch the black probe of your multimeter to ground during the measure.
No, i´ve done that. Used the ground output and the ouptput signal on the board to measure. Thanks!
mgallagher641 wrote:
defalut wrote:Sorry, a noob question again, unfortunately search is still not working so i gotta ask anyway.

I read the first post in the thread, got to the right amount when i calibrated the LM337 and measured up -6.0V.

But when i try the last one:

"3) Adjust the 100R trimpot until the output has no DC offset with the output knob at 12:00."

How do i do that? Do i plug a cable in the out port and measure in it´s end, set the out pot to dead center and fiddle with the trim pot?
Tried it, does not work. I can never get to the right amount, the trim pot starts clicking and then i´m at -080mV or something

What and how do i measure? :hmm:
You can do it that way, or you can just do this by measuring the voltage between the two pins of the output socket, to which you have soldered wires. You're looking for zero volts with the knob at 12.

To be honest, I suspect this isn't completely critical. That bottom knob is an attenuverter for the main output, so for normal audio use I have mine set at max +ve and leave it there. Getting the zero volts at 12 o'clock correct just means that the mixer will go to zero at that point. Unless getting precisely to zero is super critical for your application, e.g. for processing CVs, getting it to within 80mv should be fine, I would guess - although if someone wiser than me knows any different then please correct me!
Alright, that sounds good to me. At least i have done it basically right then. Closest i came was about 75-80mV and then not possible to come closer, but i can relax then.

Thanks guys for clearing this up for me. Lots to loearn, a little bit less now. :)
My tracks: https://soundcloud.com/mbangs

I build & sell MegaCommand units for MachineDrum, Analog 4 and MonoMachine! Pm for more info.

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Calibration NOOB

Post by Alariamusic » Wed Jul 10, 2019 1:44 pm

mgallagher641 wrote:Hi folks,

I just built one of these - the 12v version for Eurorack - using a PCB, panel, pots and knobs ordered from Thonk, and the remaining parts from Mouser. A very straightforward and easy build, and it seems to be working great. Sounds awesome, and only 4hp.

The most laborious part was identifying all the parts on Mouser. Things like the 10 pin header, I literally spent about 30 mins sifting through a million different items before locating the correct one.

So to save some work, the following link should take you to my Mouser project page with all the required components and quantities:

https://www.mouser.co.uk/ProjectManager ... 9758aa1fa0

These parts all seem to work and are the correct dimensions for the PCB.

In case the link dies or doesn't work, I also have an excel spreadsheet that I am attaching. This was downloaded from Mouser with all the part numbers, so should be easy to import into your own Mouser account. Under the BOM tab in Mouser there is an option to import a spreadsheet.

A few notes, with apologies if any of this is stating the obvious:

- My Mouser project doesn't include the pots or knobs as I got these from Thonk. So you may need to add these in. Be sure to get the right pots, as they solder to the PCB, so need to have the correct spacing of the legs.

- I ordered 4 of each of the NPN and PNP transistors and then used the HFE feature on my multimeter to choose the closest matched two of each. If you're not fussed about matched pairs, you'll only need 2 of each.

- I chose audio grade electrolytic capacitors. Who knows if this makes any difference, but I thought I might as well spend a few more pence. If you're desperate to save a tiny amount of money, cheaper options are available.

- The BOM lists various possible values for the electrolytics. I used 10uf for all three.

- For soldering the sockets, you have to make sure you are using the correct lugs. I looked at the photos of what others have done.

- Cost: while the parts came to only about £13 or so, shipping from Mouser was nearly as much again, and then with VAT the Mouser order was £31. The PCB and parts from Thonk were about £30. So all in this cost about £60. I've seen this module sold second hand for less than that. I am just getting into DIY modules and really enjoying it, so it made sense for me. I believe Mouser orders over £33 qualify for free shipping, so it would make sense to lump multiple builds together. I looked at Rapid, Farnell etc but Mouser was by far the best in terms of having everything required and being able to order small quantities.

- Finally, I was a bit shocked by how much plastic packaging came with the Mouser order. Several things were double or even triple bagged. It seemed excessive, and that plus the shipping made me think about the environmental impacts. I'm old enough to remember the days when you would just go down to your local electronics shop and they would put everything you wanted in a paper bag. That's long gone - now it's all coming from one insanely massive warehouse in Texas.

Anyway - big thanks to negativspace for putting this project out there, and to Thonk for the PCB and panel kit.
Hi there,

I just builded one of this with the BOM I'm quoting.

I'm having a hard time calibrating, measuring LM337 (one prob on ground, the other on the output of the LM337) gives me the same reading everytime (-0.447mV) no matter how I set the 2k trimpot. Voltage seems to get through the hole pcb just right, measured every component and my soldering skills are not bad but I'm a noob in DIY eurorack.

I tried inputting a 5V signal on channel 1 and moving the knob (of channel 1) changes the reading on LM377.

How are you guys doing this?

For this purpose, does the position of the knobs matter? Do you feed a signal on any INPUT?

PCB is 1.3 build so LM377 and the adjacent cap are as they show on the silkscreen.

I've read the whole post without finding a solution, that's why I'm writing.

this is driving me nuts.. hope someone can help me.

Thank you in advance guys.

PS: I'll post pics tomorrow if that helps, don't have it with me right now.

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Post by CliffordMilk » Fri Jul 19, 2019 9:46 am

This may be a stupid question but is it still necessary to use the 2K trimmer on the Euro build, where the voltage regulator is jumpered?

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Post by B0bcat » Thu Jul 25, 2019 2:31 pm

It seems to me the Euro build still uses a voltage regulator - LM337, just the +-15 regulator is omitted. So the 2k trim pot is still necessary.

For what it's worth I have just built this using the v1.3 PCB (not from any kit) and everything seems to work placing components as indicated on the silkscreen. Calibration seemed to be straightforward and I could get 6V and zero offset within a few minutes of trimming. Some photos for reference - this is my first hand-wired panel (using Thonkiconn jacks btw) so there's some room for improvement in terms of tidiness.

When calibrating, all pots were fully ccw except for the offset pot which was kept at noon. No input was applied or plugged



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Post by CliffordMilk » Fri Jul 26, 2019 1:46 am

This makes perfect sense. Thanks.

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Post by ZargZorg » Fri Jul 26, 2019 2:30 am

Is there a build guide for this? I couldn't find it.

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Post by CliffordMilk » Fri Jul 26, 2019 6:31 am

If you use the Mouser BOM in this thread and buy your pots from Thonk you should be fine just looking at the values on the silkscreen along with B0bcat's photos, above.

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Post by B0bcat » Fri Jul 26, 2019 11:13 am

ZargZorg wrote:Is there a build guide for this? I couldn't find it.
No official guide afaik, here's what I did roughly, and it seems to lead to a working module, but no guarantee obviously, and comments/corrections appreciated:


1) PCB & panel direct from MA, or Thonk, or others

2) pots and jacks from Thonk, or others; rest of BOM using Mouser cart in this thread or make your own, should run you about $12-15

3) verify PCB version as written on silk screen: 1.3 has all part orientations indicated accurately, v1.2 needs some reversed

4) if you're building for Eurorack (+-12V power), during your build omit electro cap farthest from power pins, and jumper hole 1 and 3 of the adjacent regulator (78L12) using a wire/resistor clipping instead of the 78L12 voltage regulator (because you're already supplying +-12V and don't need to reg it down from 15)

5) populate the board in your preferred order, e.g. resistors first, wire link, diodes, fuses, ceramic caps, pin header, film cap, trimmers, transistors, electro caps last (only electro caps and transistors are orientation sensitive). You can use a single 10uF electro cap and pair of 10/22/47uF electro caps (e.g. use 3 10uF caps)

6) put pots in PCB but don't solder yet. mount them to panel using washers and nuts. orient PCB and panel 90 degrees. I find blue tack helps. now solder pots.

7) mount jacks to panel using nuts. if you're using Thonkiconn orient the long ground leg pins towards the space between the top two and bottom two jacks so that they practically touch. Solder link the ground leg pins of adjacent jacks. Solder a link between the two linked pairs of ground legs to form ground pad. Connect that ground pad to the farthest hole from the panel (see my photo)

8) Connect the tip pin of each jack (the one opposite to the long sticking out ground pin) to the appropriate hole on the PCB - they're labeled 1 2 3 and output. The third pin of each jack is floating

9) trim as described in the first post of the thread. carry out trimming procedure while the module is powered and with all pots at zero and offset pot at noon, and no input jacks plugged (although some of that might not matter). Take ground from one of the middle pins of your power strip. For the first trimming step, take the voltage regulator output (middle leg of transistor thingie closest to power supply). For the offset calibration, take the voltage at the output cable terminal that you soldered

10) test your module by applying three sound sources to inputs 1 2 3. with output at noon bringing in individual channels should not let too much sound pass if you did offset calibration (2nd calibration step) right. With output high (or low) enough (i.e. different from noon) so as to let sound pass, individual channels should start clipping in a very pleasant way (that's what you paid money for) at 2 or 3 pm of each channel's pot setting.


That's all I can think of from the top of my head. Let me know if you have further questions as long as my build is still fresh :mrgreen:
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Post by ZargZorg » Tue Aug 06, 2019 3:23 am

About to buy the mouser bom from mgallagher641
First time DiY something.
What's the wire I should get to connect the jacks to the pcb.
Thanks

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Post by 555x555 » Tue Aug 06, 2019 12:18 pm

ZargZorg wrote:About to buy the mouser bom from mgallagher641
First time DiY something.
What's the wire I should get to connect the jacks to the pcb.
Thanks
Most anything will do, but in case you have nothing at all, here's some good wire for this purpose:
http://smallbear-electronics.mybigcomme ... t-sampler/

Tons of wire on mouser, too, but since probably you'll have to order pots and knobs from smallbear anyway, you may as well...

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Post by ZargZorg » Wed Aug 07, 2019 12:31 pm

I'm actually ordering the jacks and pots from thank so will this stuff do?
I have an order up on tayda.

https://www.taydaelectronics.com/90624- ... solid.html

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Post by 555x555 » Wed Aug 07, 2019 12:45 pm

It'd work, but you probably want stranded rather than solid wire.

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Post by degeneratedsines » Sat Aug 10, 2019 1:19 am

If you are ordering from Thonk, this is what I use: https://www.thonk.co.uk/shop/ribbon-cable-24awg/
My build is displayed page 31. This was my very first DIY module build.
Just don't get PJ302M jack like I did, they don't fit in the case. I had to replace them with something else.

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Re: Calibration NOOB

Post by Alariamusic » Wed Aug 14, 2019 10:56 am

Alariamusic wrote:
mgallagher641 wrote:Hi folks,

I just built one of these - the 12v version for Eurorack - using a PCB, panel, pots and knobs ordered from Thonk, and the remaining parts from Mouser. A very straightforward and easy build, and it seems to be working great. Sounds awesome, and only 4hp.

The most laborious part was identifying all the parts on Mouser. Things like the 10 pin header, I literally spent about 30 mins sifting through a million different items before locating the correct one.

So to save some work, the following link should take you to my Mouser project page with all the required components and quantities:

https://www.mouser.co.uk/ProjectManager ... 9758aa1fa0

These parts all seem to work and are the correct dimensions for the PCB.

In case the link dies or doesn't work, I also have an excel spreadsheet that I am attaching. This was downloaded from Mouser with all the part numbers, so should be easy to import into your own Mouser account. Under the BOM tab in Mouser there is an option to import a spreadsheet.

A few notes, with apologies if any of this is stating the obvious:

- My Mouser project doesn't include the pots or knobs as I got these from Thonk. So you may need to add these in. Be sure to get the right pots, as they solder to the PCB, so need to have the correct spacing of the legs.

- I ordered 4 of each of the NPN and PNP transistors and then used the HFE feature on my multimeter to choose the closest matched two of each. If you're not fussed about matched pairs, you'll only need 2 of each.

- I chose audio grade electrolytic capacitors. Who knows if this makes any difference, but I thought I might as well spend a few more pence. If you're desperate to save a tiny amount of money, cheaper options are available.

- The BOM lists various possible values for the electrolytics. I used 10uf for all three.

- For soldering the sockets, you have to make sure you are using the correct lugs. I looked at the photos of what others have done.

- Cost: while the parts came to only about £13 or so, shipping from Mouser was nearly as much again, and then with VAT the Mouser order was £31. The PCB and parts from Thonk were about £30. So all in this cost about £60. I've seen this module sold second hand for less than that. I am just getting into DIY modules and really enjoying it, so it made sense for me. I believe Mouser orders over £33 qualify for free shipping, so it would make sense to lump multiple builds together. I looked at Rapid, Farnell etc but Mouser was by far the best in terms of having everything required and being able to order small quantities.

- Finally, I was a bit shocked by how much plastic packaging came with the Mouser order. Several things were double or even triple bagged. It seemed excessive, and that plus the shipping made me think about the environmental impacts. I'm old enough to remember the days when you would just go down to your local electronics shop and they would put everything you wanted in a paper bag. That's long gone - now it's all coming from one insanely massive warehouse in Texas.

Anyway - big thanks to negativspace for putting this project out there, and to Thonk for the PCB and panel kit.
Hi there,

I just builded one of this with the BOM I'm quoting.

I'm having a hard time calibrating, measuring LM337 (one prob on ground, the other on the output of the LM337) gives me the same reading everytime (-0.447mV) no matter how I set the 2k trimpot. Voltage seems to get through the hole pcb just right, measured every component and my soldering skills are not bad but I'm a noob in DIY eurorack.

I tried inputting a 5V signal on channel 1 and moving the knob (of channel 1) changes the reading on LM377.

How are you guys doing this?

For this purpose, does the position of the knobs matter? Do you feed a signal on any INPUT?

PCB is 1.3 build so LM377 and the adjacent cap are as they show on the silkscreen.

I've read the whole post without finding a solution, that's why I'm writing.

this is driving me nuts.. hope someone can help me.

Thank you in advance guys.

PS: I'll post pics tomorrow if that helps, don't have it with me right now.
This is still driving me nuts.. here are some pics.

Do you guys see anything wrong?



Image
Image
Image

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jpeterman
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Post by jpeterman » Wed Sep 11, 2019 12:56 am

So thonk completely fucked up my order and sent me vertical mount instead of right angle mount. Is it ok to use these? I'm guessing I could bend the 3 legs and cut off the remaining mounting part.

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Post by jpeterman » Fri Sep 20, 2019 5:17 pm

Nvm, just got replacements from thonk. How exactly do you do the calibration process? This is my first build.

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Re: [IN STOCK] DTM: Moog CP3-type discrete mixer PCB, Euro panel

Post by CollinRussell » Thu Aug 13, 2020 7:53 pm

Bought the Synthcube V1.3 full kit. They sent me 2x 10uF electrolytics and 1x 4.7uF electrolytic.
This doesn't match the silkscreen or the BOM on page 1 of this thread.

Question 1. Did they send me the wrong parts?
Question 2. What value of electrolytic cap is for the non-designated spots by the beads?

Any help would be great.
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