[Closed] Benjolin PCB In Eurorack

cane creek · Post by **cane creek** » Wed Nov 23, 2016 10:12 am

Just waiting for Panel now, i won't solder Pots/sockets without a Panel.

MatrixModulator · Post by **MatrixModulator** » Mon Nov 28, 2016 1:54 am

Having a hard time finding the correct switches.
Would theses work fine?

http://www.ebay.ca/itm/5-x-On-Off-Sub-M ... SwDwtUoIq-

I'm in Canada, shipping kills the deals online.. and ups charges a lot of fees (from newark)

sockmonkey · Post by **sockmonkey** » Mon Nov 28, 2016 3:45 am

Does anyone else have a problem where the module outputs a DC offset the first time it's powered up, functions normally after a power cycle? Any solutions?

diablojoy · Post by **diablojoy** » Mon Nov 28, 2016 11:17 pm

Having a hard time finding the correct switches.
Would theses work fine?

hmm 28 H x12.5 W x 11mm L
seems like miniature / sub miniature get confused all the time - evilbay is rife with incorrect descriptions
here is a pic of a sub miniature switches dimensions for future reference
dimensions should be fairly close to this if it is to fit
- so around 19 H x 6.1 W x 8.9 mm L
the actual body height (9.4mm) is fairly important as the 9mm vertical pots and jacks used wont reach the board if it is much larger, equally the pin hole size and spacing is important

Puzzler · Post by **Puzzler** » Wed Dec 14, 2016 10:29 am

can anyone please confirm that using this 79L09 is correct?
https://www.reichelt.de/ICs-A-A-/-A-79L ... OUPID=2908

Somehow the benjolin is behaving strangely, even though i made the schottky diode mod for the V2164.
Sound goes on and off etc. Touching the case frame "sometimes" changes sound? maybe a ground problem?!

i even removed the CV pots for testing though.

Puzzler · Post by **Puzzler** » Sat Dec 17, 2016 5:39 pm

Haaaaalp

diablojoy · Post by **diablojoy** » Sat Dec 17, 2016 8:03 pm

can anyone please confirm that using this 79L09 is correct?
https://www.reichelt.de/ICs-A-A-/-A-79L ... N=3&LA=3&A RTICLE=23508&GROUPID=2908

appears to be T092 100mA version so should be correct from the BOM note I don't actually have a build of this myself to check against.

Haaaaalp

hmm post a good picture of both sides of your board and try to describe problem in detail maybe post an audio file of what is happening

hippasus · Post by **hippasus** » Sun Dec 18, 2016 1:28 am

I just populated the pcb, minus cv sockets and pots, I only solder six pots and in the outs only the main out while waiting to find a panel.
Is it possible to test it like that? I am going to blow something if I connect the power?
Thanks

pieter · Post by **pieter** » Sun Dec 18, 2016 10:19 am

hippasus wrote:I just populated the pcb, minus cv sockets and pots, I only solder six pots and in the outs only the main out while waiting to find a panel.
Is it possible to test it like that? I am going to blow something if I connect the power?
Thanks

I wouldn't do that because you may not have all the ground connections in place, but maybe somebody more experienced here can correct me if I'm wrong.

sleepgardens · Post by **sleepgardens** » Sun Dec 18, 2016 12:20 pm

hippasus wrote:I just populated the pcb, minus cv sockets and pots, I only solder six pots and in the outs only the main out while waiting to find a panel.
Is it possible to test it like that? I am going to blow something if I connect the power?
Thanks

I did this and nothing blown up. I did it to measure voltages outputs of transistors and they were fine. Can't be sure on your build though.

Puzzler wrote:can anyone please confirm that using this 79L09 is correct?
https://www.reichelt.de/ICs-A-A-/-A-79L ... OUPID=2908

Somehow the benjolin is behaving strangely, even though i made the schottky diode mod for the V2164.
Sound goes on and off etc. Touching the case frame "sometimes" changes sound? maybe a ground problem?!

i even removed the CV pots for testing though.

Don't know german but here are the specs of the one I got if they can somehow help:
Input Voltage Max: 0V
Input Voltage Min: -35V
Linear Regulator Case Style: TO-92
MSL: -
No. of Pins: 3
Operating Temperature Max: 1254°C
Operating Temperature Min: 0°C
Output Current: 100mA
Output Voltage Nom.: -9V
Packaging: Each

Puzzler · Post by **Puzzler** » Sun Dec 18, 2016 7:05 pm

Hello,

here are some pictures. So i finally installed the CV pots as well. To see if the problem will change after that.
You can see my easy workaround for the faulty PCB layout.

The sound from the "main out" is now more harmonic but still i think its not correct, mot what the module should do.
Sound goes on and off sometimes, but it seems not being related to the work of the rungler, so its unwanted behavior imho.

And other strange phenomena:
Power ON, sound is on, Power off, still the sound is audible, but much more quiet ofc. So i think its a ground problem.

Mono 3.5 jack goes to 6.3 jack in a "Native Instruments Komplete Audio 6". When i slightly pull out the 6.3 jack off the audio interface, the sound gets more quiet, but sound wise more precises, less noise.
Maybe some PSU voltage is mixing to the sound cause of ground problem?

Anyway, i cant figure out, where the ground problem might be on the pcb.

EDIT:

I tested my second module and it sounded similar distorted, but suddenly after several PSU switch on/off it started sounding clean.

But now ONLY "Pulse A" is very quiet.

So i went back to module 1 and suddenly it also sounds clear.

Aaaan "Pulse A" also is quiet.

Now i pulled out the 6.3 jack a little little bit and suddenly the pulse is loud as expected.

Pushing it back in fully makes it quiet again.

And NO its not a problem of the PSU, the jack nor the audio interface. The issue is not reproducable with any of my other modules.

diablojoy · Post by **diablojoy** » Mon Dec 19, 2016 1:01 am

edit

I tested my second module and it sounded similar distorted, but suddenly after several PSU switch on/off it started sounding clean.

hmm that possibly may have been IC socket related - did you resocket any IC's during this or just power cycle ? either way it may have cleared up with cycling the power

diablojoy · Post by **diablojoy** » Mon Dec 19, 2016 1:29 am

Now i pulled out the 6.3 jack a little little bit and suddenly the pulse is loud as expected. Pushing it back in fully makes it quiet again.

And NO its not a problem of the PSU, the jack nor the audio interface. The issue is not reproducable with any of my other modules

OK that is a little weird unbalanced output to balanced input should be all right
have you used that particular cable before ok ? maybe meter it and compare the barrel/tip length/shape with another its the only thing I can think of at the moment that might cause that

Puzzler · Post by **Puzzler** » Mon Dec 19, 2016 12:56 pm

I could specify the issue with the jack. The PJ301M-12 has 3 Pins.
According to this datasheet https://www.thonk.co.uk/wp-content/uplo ... asheet.pdf

pin 2 and 3 are connected if no jack is inserted.

So if i insert a jack which just touches the still connected pin 2 and 3, then i can hear sound.
If i insert the jack fully, so the connection between pin 2 and 3 is disconnected, the sound goes off.

I set knobs for freq of Triangle A to any value. Example voltage was 0.18V on pin 2 and 3.
When i plugged in the jack fully, the voltage on pin 3 raised to 3.44V and 0.00 on pin 2 ofc. But why??

The Filter is not filtering the full signal. it seems as if its only a lowpass on the signal which comes from the "rungler freq" part of the module. jaja, cant read schematics too good (yet).

There is will always be high frequencies even if the knob is fully CCW.

Puzzler · Post by **Puzzler** » Mon Dec 19, 2016 1:01 pm

Ok, i was thinking about this.

Somebody also linked this post by Rob himself suggesting this:

When you run the board with a power supply it is a very good idea to solder two diodes instead of the two battery connections. Do it in a way that the cathode of the diode is connected to the + of the battery connector and the anode connects to the - connection. This way the diodes do NOT conduct. The reason why this is a good idea is to insure proper startup of the voltage regulators when powering up. Without these diodes there is a chance that one power regulator starts up before the other and this will prevent the other from starting up, resulting in silence. The diodes fix this properly. If you use a non-symmetrical power transformer, like a wallwart thingy, two rectifier diodes and two elcos, either the + or the - voltage comes up before the other one, and that voltage will pass a regulator and make the other regulator sense an "inverted" voltage on its output and force the other regulator into permanent short circuit protection mode. The diode will short this "inverted" voltage to ground and assist the other regulator when it comes up just a fraction of a second later. These diodes can be simple 1N914 types.

what if i have this issue nevertheless. where would i install these 2 other schottky diodes?

solder two diodes instead of the two battery connections

???

diablojoy · Post by **diablojoy** » Tue Dec 20, 2016 3:30 am

what if i have this issue nevertheless. where would i install these 2 other schottky diodes?

ah ok his description is purely for the original board not this euro version

So for this board I would go with -
on the euro power header pins solder side of the board
solder one diode from a positive 12v pin to a ground pin (cathode towards positive pin)

solder 2nd diode from a negative 12v pin to a ground pin (cathode towards ground pin) note this diode actually duplicates the ssm2164 protection diode if you did that mod already
make certain of the diode polarities, triple check it before powering the module .

jestern77 · Post by **jestern77** » Thu Dec 22, 2016 10:45 am

jestern77 · Post by **jestern77** » Thu Dec 22, 2016 10:46 am

which one is r49? And r36?

flts · Post by **flts** » Thu Dec 22, 2016 10:52 am

jestern77 wrote:which one is r49? And r36?

R49 is the only 510k there is marked on the board - as you can see there is no 510k on the BOM, so replace the only one of those you can find on the board with 510R. If you look at the relevant part of https://github.com/kweiwen/benjolin/wik ... the-module you can see "VR8" on one of the pots on the silkscreen in the image (why the part names are left off production PCBs, I don't know), the resistor is on the left side of that one.

Likewise, R36 is the only 150k resistor on the board, you can see from the BOM there is only one. I think it was somewhere on the bottom right sector of the PCB as well.

flts · Post by **flts** » Thu Dec 22, 2016 10:55 am

Seems like mine is working fine so far...

jestern77 · Post by **jestern77** » Thu Dec 22, 2016 3:14 pm

Thanks so much! Another question, about this resistor I can't quite understand..
It's like a 30 on the pcb .. what is its value?

jestern77 · Post by **jestern77** » Thu Dec 22, 2016 3:17 pm

Oh I get it, is another 30k?

flts · Post by **flts** » Thu Dec 22, 2016 3:19 pm

There was at least one quite unclearly marked 30k on the PCB, might have been that one... At least there is a boatload of 30k resistors in the PCB so chances are that one is another of them

jestern77 · Post by **jestern77** » Thu Dec 22, 2016 3:38 pm

yeah I did it and I think it's the 30k resistor I checked the pictures of other mufflers around. Or maybe everybody's got it wrong..

kweiwen · Post by **kweiwen** » Sun Dec 25, 2016 10:19 am

jestern77 wrote:Thanks so much! Another question, about this resistor I can't quite understand..
It's like a 30 on the pcb .. what is its value?

it's 30k

the "k" was eaten by the via haha

MUFF WIGGLER

MUFF WIGGLER

[Closed] Benjolin PCB In Eurorack

minimum test

Re: minimum test

Re: minimum test