PMFoundations Clock Divider User manual

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Clock Divider v1.0a –Assembly Guide
Thank you for purchasing this module! This is an average build with some precision integrated
circuits. Some of the pads are quite small and you will need a chisel tip or screwdriver tip soldering
iron and the skill to solder these tiny joints.
The module is designed and sized for Eurorack systems. You will need a 16-10 pin eurorack power
ribbon connector with –12/0/+12 which is connected to a synth power supply.
Follow the parts lists, these instructions and the PCB silkscreen text to build the module.
The module consists of 1 PCB board and a front panel.
You must follow the order of assembly as described below since some components will be soldered
underneath other components.
NOTE: Build options

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Pulse level:
R5, 6, 12, 13, 18, 19, 22, 23, 25, 26, 28, 29, 32, 33 set the clock output pulse voltage level. The
following options are suggested:
•STANDARD BUILD: 5V pulse: R5,12,18,22,25,28,32 = 1.8K; R6,13,19,23,26,29,33 = 1.5k
•10V pulse: R5,12,18,22,25,28,32 = 1.2K; R6,13,19,23,26,29,33 = 11k
Jumpers:
The jumpers set the clock mode of the divider. Jumper adjustable clock pulse detection
determines whether the rising edge or falling edge triggers the divisions.
If you want rising edge mode, put wire links between A2-A3 and B2-B3. If you want falling edge
mode, put wire links between A1-A2 and B1-B2. Alternatively, you can use a proper six pin
jumper and two shunts to short the appropriate pins as shown in the photo.

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Constructing the board
1. Resistors
See above for options.
Install the flat resistors on the TOP of the board. Solder and clip the leads.
2. Diodes

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Install the diodes on the TOP of the board. These are polarized components. Align the stripe on
the diode with the stripe marked on the board. Solder and clip the leads.

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3. IC Sockets
Now Install the sockets on the TOP of the board. Observe the notch or mark on the sockets and
align with the notch or mark on the board. Solder.
4. Power socket
Install the 10 pin power socket on the TOP of the board. This must be installed with the correct
orientation or the module will be damaged when the power is connected.
The cut-out in the socket should face the jacks, aligning the cut-out with the "10" marking on
the board as shown in the photo. Solder on the underside.

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5. 6 pin jumper (JP1)
See above for options.
For standard operation: Put wire links from A2-A3 and from B2-B3.
6. Ceramic/film/polypropylene capacitors
Install the ceramic/film capacitors on the TOP of the board. Solder and clip the leads.
7. Transistors
Install the transistors on the TOP of the board. These are polarized components. Align the
outline with the outline on the board. They should be raised off the board surface slightly and
at the same height. Solder and clip the leads.

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8. Electrolytic capacitors
Install these on the TOP. Make sure you orient these capacitors correctly. The longer lead
and/or the lead marked with a + needs to be inserted into the hole that has the “+” marking
near it. Leads marked with “-“ go in the board hole WITHOUT the “+”. Solder and clip the leads.
9. 3.5mm Jack Sockets
Tack one pin of each only with solder. These will be finalized later. Please ensure they are on
the CORRECT SIDE OF THE BOARD.
10. Switch
Tack one pin of the switch, align with the front panel, then solder all the remaining pins and the
locating lugs.

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11. Alignment
1. Place the front panel over the board so that the 3.5mm jacks align with the holes in the
panel.
2. Put nuts on the jacks and FULLY TIGTEN all of them. Do not overtighten!
3. Now fully solder as many pins as you can reach of each jack and switch.
4. Remove the front panel and solder all the remaining pins on the jacks and switches.
5. If you cut off the ends of the pins of the jacks, near to the solder joint, the module will be
easier to fit into your rack close to other modules.
12. LEDs
Bend the pins of the LEDs as shown in the photo. The bend is at 12.5mm (1/2") from the
underside of the LED. Note the location of the longest lead.

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Place the panel over the jacks and pots and position the LED in the holes.
Place the short lead into the pad with the flatted edge of the silk screen next to it. Solder and
clip the leads.
13. If you do not trust all your soldering and connections, carry out the voltage tests below before
installing the remaining ICs
Voltage tests
1. You do not have to do these tests if you are completely happy with your soldering and are sure
there are no bridges or incorrectly placed components. However, these tests will ensure that
the correct power supplies are sent to the IC pins to ensure they will not be damaged on power
up.
2. Plug in the power supply and connect the –VE probe of a multimeter (set to the 20V DC range)
to one of the GROUND pins of the jacks. The GROUND pin is nearest to the edge of the board.
3. Check the voltage at the following points on the board:
a. At IC1 pin 14 approx = +12V
b. At IC1 pin 7= 0V
c. At IC2 pin 7 approx = +12V
d. At IC2 pin 2 approx = +2V
e. At IC2 pin 3= 0V
f. At IC3 pin 14 approx = +12V

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g. At IC3 pin 7= 0V
h. At IC4 pin 14 approx = +12V
i. At IC4 pin 7= 0V
j. At IC5 pin 14 approx = +12V
k. At IC5 pin 7= 0V
l. At IC6 pin 14 approx = +12V
m. At IC6 pin 7, 12, 13= 0V
n. All other pins should not show anything close to +12V or -12V
4. If any of these tests fail to match the readings given, you should check the components and
soldering before progressing
Final Assembly
1. Place the ICs in place by aligning the notch with the notch graphic on the PCB Silk Screen and
notch on the sockets.
2. Put the caps on the switches by pushing each cap until it clicks.

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