Showing posts with label DIY. Show all posts
Showing posts with label DIY. Show all posts

Thursday, 6 July 2017

NLC PSU build 2

This is a smaller version of a Nonlinearcircuit PSU I built earlier.
http://djjondent.blogspot.com.au/2017/02/power-supply-nlc-build-notes.html

It uses a 12VAC Wall Wart power adapter.
The AC output of the wall wart is rectified with diodes so that positive voltage gets stored on the caps that serve the positive voltage regulator (LM7812) and negative voltage gets stored on the caps that serve the negative voltage regulator (LM7912).

I'm putting together this PSU for an old Serge modular but its actually for Eurorack.
The serge uses +12, -12, +6 and ground so I will have to add a 6V regulator to this later.

Some pics:


The PCB receives 12VAC from a plugpack/ wallwart
. The 1N4004 diodes split this into positive and negative waveforms.

The 4700uF capacitors then smooth out these waves
. The 7812 and 7912 regulators then convert the rectified & smoothed
signals to +12V DC and -12V DC and these are fed to the connectors to be distributed to your lovely modules.
I'm using 250v TDK film caps for the four small 100nf caps

 Poor Grandma.
Let's Eat Grandma is a British musical group formed in 2013 by childhood friends Rosa Walton and Jenny Hollingworth. 

I decided to use 1K resistors for the LEDs

 Some pics of the additional 6V regulator circuit.
 Using a LM7806
 330nf on the left. 100nf on the right.


Red +12V, Black 0V, White -12V, Green +6V

----------------------
A second build.
I have a very confined case.
 tRYING TO keep everything as flat as possible.



Sunday, 2 July 2017

Paperface Serge - Negative Slew restoration

Serge  Negative Slew restoration.
These are some notes for repairing a old Negative Slew.


The main panel is here
http://djjondent.blogspot.com.au/2017/06/serge-paperface-restoration-warren-burt.html 

The board is marked R9
This is the lower section of the PCB.
The upper section works.
According to Ken Stone's site there are two problems with this.
It's missing one trace and a 4.7k resistor.
I've marked the missing trace in orange.

Also marked the missing 4.7k resistor in orange.

4.7K resistor added.
I removed the 3900 opamp. lots of corrosion in the socket.
Replaced & it works.
:-)
Thanks Ken



Links:
2. CGS
3. Muffs
The 1973 PCB used +12, +6, -12 & ground.
The 1975 PCB used +/-12 V & ground.
So I'm guessing this is a 1975 PCB  as it uses +/-12 & 0V unless it has a on board 6V regulator.

The module uses two ICs
LM3900. It's a quad op amp

 Ground at pin 7, power is pin 14.

LM3046 
This is a transistor array.
It consists of five general purpose silicon NPN transistors. Two of the transistors are internally connected to form a differentially-connected pair.  



PCB connections:
A = input (1)
B = output (1)
C = VC (1)
D = pulse out (1)
E = input (2)
F = output (2)
G = VC (2)
H = pulse out (2)
U = not used (0v)
W = 0v
X = +12v
Y = +6v
Z = -12v




Thursday, 29 June 2017

Array - Knight Rider - & initialize PinMode - Arduino

 This is a exercise in Arrays
It makes use of 6 LEDs connected to the pins 2 - 7 on an arduino uno using 220 Ohm resistors.
They are triggered like the lights of "KIT" - the car belonging to the Hoff.

A bit about arrays first.
They are a list or collection of variables that can be accessed via an index number. 
      The word "array" isn't actually used. The symbols [] and {} do the job.
      eg: int myArray[] = {6,21,34,2,1,0,152}; 
      Here we declared an array with 7 values.  Arduino creates 7 places in memory for these values.
 
     We can also just tell the arduino to create 7 memory spots, and then enter the values later :
      int myArray[7];
 
To assign a value to the second spot we use a command like this:
myArray[1] = 21; 
This is the index number.
The first spot always has an index value of 0 (they are zero indexed).
 
Code 1
Link:
 
Such a simple piece of code.
This is a great way of cycling through different lists.
In this example we use the array to choose which LED to light. 
It could just as easily be a menu.
Another way might involve using the "switch case".... will cover in another post
 
 // ******************************************************************************
/* Knight Rider 3
* --------------
*
* This example concentrates on making the visuals fluid.
*
*
* (cleft) 2005 K3, Malmo University
* @author: David Cuartielles
* @hardware: David Cuartielles, Aaron Hallborg
*/
int pinArray[] = {2, 3, 4, 5, 6, 7};
int count = 0;
int timer = 30;
void setup(){
for (count=0;count<6;count++) {
pinMode(pinArray[count], OUTPUT);
}
}
void loop() {
for (count=0;count<5;count++) {
digitalWrite(pinArray[count], HIGH);
delay(timer);
digitalWrite(pinArray[count + 1], HIGH);
delay(timer);
digitalWrite(pinArray[count], LOW);
delay(timer*2);
}
for (count=5;count>0;count--) {
digitalWrite(pinArray[count], HIGH);
delay(timer);
digitalWrite(pinArray[count - 1], HIGH);
delay(timer);
digitalWrite(pinArray[count], LOW);
delay(timer*2);
}
}
// ********************************************************* 
 

 Use 220 ohm resistors.
Cathode of the LEDs connect to gnd.
//88888888888888888888888888888888888
This second bit of code is really useful for setting all your pins
to output mode for example. 
Rather than having to type & initialize each pin as an output.
The section in the void setup is the bit that does it. 
//88888888888888888888888888888888888888888
/*
   Array sketch with for loop()
   an array of 3 LEDs that blink consecutively
*/

// create array of output pins for LEDs
int ledPin[] = {10, 11, 12};

void setup()
{
  //  for loop to set all ledPins to output mode
  for (int index = 0; index < 3; index++)
  {
    // declare LED as output
    pinMode(ledPin[index], OUTPUT);

  } //close for loop()
} // close void setup()

void loop()
{

 // for loop() to blink LEDs consecutively
  for (int i = 0; i < 3; i++)
  {
     // set LEDpins HIGH
    digitalWrite(ledPin[i], HIGH);
    // add 1 second delay
    delay(1000);
    // set LEDpins LOW
    digitalWrite(ledPin[i], LOW);
  } // closing for loop()

} // close void loop() 
 
 
//8888888888888888888888888888888888888888888888888888888888 
 Links
+ https://www.tutorialspoint.com/arduino/arduino_arrays.htm
 
 ---------------------------------
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Tuesday, 27 June 2017

Serge Paperface Restoration - Warren Burt - 2/2

Finally I'm getting around to fixing the Warren Burt Serge Modular.
I think I purchased this synth back in 2013.
http://djjondent.blogspot.com.au/2013/12/the-warren-burt-sergedriscoll.html
Sorry Warren that its taken so long to get started.

This is the second panel from the second box.



    Panel 2 of Box 2:
  • 1 Dual Positive Slew
  • 1 Dual Negative Slew
  • 2 Envelope Generators
  • 1 Triple Bi-directional Router
  • 1 Triple Comparator
  • 1 Schmitt Trigger 

----The power supply for this panel consists of  +12, -12, +6, & ground


---------------------------------------------------------------------------
Schmitt Trigger & Triple Comparator


The Blue wire seems to be ground. (marked as "W" on PCB)
The Green is I think +6V (Marked as "Y" on the PCB)
The PCB is labelled R11 

Below are some extra pics I have from a surplus vintage PCB.
Might be of use.


Links:

---------------------------------------------------------------------

Bi directional router
This is marked as R4 on the PCB.
Links:

 Double check the wiring by looking at what the pads are labeled.
X=+VE
W=0V
Z=-VE

In this case, 
The blue wire at the bottom is -12V
Red is +12V
There is no 0V/GND connection to this module.
-------------------------------------------------------------------------------------
Envelope Generator. We have 2 of these

The boards are I believe 1st generation ... from 1973


Links:

 Double check the wiring by looking at what the pads are labeled.
X=+12V
Y=+ 6V
W=0V


Blue (near the pots is marked W on the PCB) is ground.
Red (X) = +12V
Green (Y on PCB) = ??? My guess is its +6v.


Below are some pics from an extra Envelope Generator PCB. Its marked R7 so 
is possibly also 1st generation, 1973.
This is not part of the Warren Burt pile but it might help me work things out.
Lovely dark blue colour too.





I think this is a voltage divider circuit to create 6V from 12V.

----------------------------------------------------------

Negative slew

Links:
2. CGS
3. Muffs

The 1973 PCB used +12, +6, -12 & ground.
The 1975 PCB used +/-12 V & ground.
So I'm guessing this is a 1975 PCB  as it uses +/-12 & 0V unless it has a on board 6V regulator.

The upper slew was working.
But not the lower. So i needed to trouble shoot this.
-----------------------------------------------------------------------------------
Positive Slew



Links:
2. CGS

This module appears to need +/-12V, +6V & ground
 The PCB is labelled R10.
X= +12V
Y= +6V
W= 0V
Z= -12V


Tuesday, 20 June 2017

Multi-Band Distortion - NLC Build notes

These are my build notes for the Nonlinearcircuits Multi Band Distortion module.
It's in Eurorack format.
Andrew has based the layout on a Buchla 194 filter.

This is a fixed 4 channel bandpass from the late 1960's.
He has however added some goodies: Some Fuzz circuits & four Korg 3200 VCAs.
The distorted signal can be mixed with the clean signal . The VCAs use vactrols and allow CV control of the mix.

Andrew's build notes are here:
http://www.sdiy.org/pinky/data/MBD%20BOM%20and%20build.pdf

There are some useful links in the NLC blog:
http://nonlinearcircuits.blogspot.com.au/2015/02/multi-band-distortion-processor.html

Some pics of the virgin PCB and faceplate first.

Some NLC words of wisdom:

Jack Smith was born on November 14, 1932 in Columbus, Ohio, USA. He was an actor, known for Flaming Creatures (1963), Chumlum (1964) and Scotch Tape (1963). He died on September 25, 1989 in Manhattan, New York, USA.

I like to get the ICs on first.
Then the rest of the SMDs
Now for the rest of the through hole stuff:
resistors, headers, caps, etc
Trannies

Vactrols next.
The white dot on the vactrol is the cathode.
On the PCB, the cathode is marked "k"


Jacks & Pots. All B100K
And the faceplate.
Another one done. :-)
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You can find more NLC builds here.
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