7Dials CV Express User manual

Thank you for your purchase of the 7Dials CV Express module. We hope you nd this unit to be a creative
addition to your modular synthesiser.
This build guide will show you how to build the CV Express module, focusing on our kit for the popular
Eurorack format.
The assembly of this DIY module will only require a small amount of elementary electronics
knowledge, but (like any DIY project) it does require a good level of soldering ability. If you are yet to
acquire soldering skills or experience then we would recommend you rst practice on some simpler kits.
This project is not by any means a difcult build, but it wouldn’t really be considered an ideal starting
project for a total beginner.
There are some really good DIY learning resources and soldering tutorials available online,
for example:
Adafruit-Soldering-Guide
If you’re building the CV Express from one of our kits, please make sure you rst check the quantities and
component values of all parts against the BOM provided. All resistors of multiple quantities should have
their values noted on the tape. Single quantity resistors will need to be identied by the builder, we’ve
included a list of all the relevant resistor colour codes needed for this project. It’s certainly worth double
checking that the correct resistors are all going in the right spots.
100k - Brown-Black-Black-Orange--Brown
110k - Brown-Brown-Black-Orange--Brown
1k - Brown-Black-Black-Brown--Brown
390r - Orange-White-Black-Black--Brown
36k - Orange-Blue-Black-Red--Brown
4k7 - Yellow-Violet-Black-Brown--Brown
2k - Red-Black-Black-Brown--Brown
4m7 - Yellow-Violet-Black-Yellow--Brown
100r - Brown-Black-Black-Black--Brown
10k - Brown-Black-Black-Red--Brown
200k - Red-Black-Black-Orange--Brown
220k - Red-Red-Black-Orange--Brown
220r - Red-Red-Black-Black--Brown
If you’re not building from a kit please refer to the BOM where we list part numbers and provide links to
various suppliers. All of the links are provided only as an aid to help the diy builder nd or compare the ap-
propriate part required for this project.
Any links provided in this manual are not to be seen as an endorsement of that product.
If you are sourcing your own parts and have any questions, please don’t hesitate to contact us, we’ll be
happy to help in any way we can. Builders can also check out the dedicated 7Dials CV Express Muffs
thread:
https://www.muffwiggler.com/forum/viewtopic.php?t=145913&start=0
CV Express build guide version 1.0
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Build order
Prior to installing the resistors you rst need to check and conrm the values, either visually, using the
provided colour codes, or by measuring with a multimeter.
CV Express build guide version 1.0
1.
Locate and install the single 390r resistor in the place marked R29.
390r resistors are marked - Orange-White-Black-Black--Brown
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CV Express build guide version 1.0
2.
Next, Install the single 36k resistor in the place marked R4.
36k resistors are marked - Orange-Blue-Black-Red--Brown
3.
Next, Install the single 4.7m resistor in the place marked R9.
4m7 resistors are marked - Yellow-Violet-Black-Yellow--Brown
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CV Express build guide version 1.0
4.
Next, Install the single 100r resistor in the place marked R10.
100r resistors are marked - Brown-Black-Black-Black--Brown
5.
Next, Install the single 220k resistor in the place marked R21.
220k resistors are marked - Red-Red-Black-Orange--Brown
** Double check you don’t mix up the 220k and 220r resistors **
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CV Express build guide version 1.0
6.
Next, Install the single 220r resistor in the place marked R31.
220r resistors are marked - Red-Red-Black-Black--Brown
7.
Next, Install the pair of 4.7k resistors in the places marked R6 & R11.
4k7 resistors are marked - Yellow-Violet-Black-Brown--Brown
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CV Express build guide version 1.0
8.
Next, Install three 10k resistors in the places marked on the Front Panel Component PCB as R13, R23 &
R30.
10k resistors are marked - Brown-Black-Black-Red--Brown
9.
Next, Install four 2k resistors in the places marked on the Front Panel Component PCB as R7, R17, R25
& R34.
2k resistors are marked - Red-Black-Black-Brown--Brown
** Double check you don’t mix up the 2k and 200k resistors **
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CV Express build guide version 1.0
10.
Next, Install four 200k resistors in the places marked R18, R22, R28 & R39.
200k resistors are marked - Red-Black-Black-Orange--Brown
11.
Next, Install the pair of 110k resistors in the places marked R15 & R40.
110k resistors are marked - Brown-Brown-Black-Orange--Brown
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CV Express build guide version 1.0
12.
Next, Install the ve 1k resistors in the places marked R3, R8, R20, R27 & R38.
1k resistors are marked - Brown-Black-Black-Brown--Brown
13.
Next, Install the fourteen 100k resistors in the places marked R1, R2, R5, R12, R14, R16, R19, R24, R26,
R33, R35, R36, R37 & R41.
100k resistors are marked - Brown-Black-Black-Orange--Brown
13.
Now move onto soldering the diodes. There are a few different types included in the CV Express kit and
it’s very important that they are all put in the right places and also that they are all orientated correctly.
It’s also important not to linger too long with the soldering iron when installing diodes, they can easily be
damaged by excessive exposure to heat.
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CV Express build guide version 1.0
14.
Install the pair of 1n4148 diodes in the places on the pcb marked D1 & D2. (2x loose in cap bag, small red
body/black band on one end)
Please refer to the picture, it’s very important that the black band is orientated correctly with the white
stripe silkscreen marking on the pcb.
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CV Express build guide version 1.0
15.
Next, Install the pair of 1n4001 diodes in the places marked D4 & D5 (2x in cap bag, large black body/
silver band on one end)
Please refer to the picture, it’s very important that the silver band is orientated correctly with the white
stripe silkscreen marking on the pcb.
Next we proceed with installing the caps.
All of the ceramics caps are bipolar, so orientation is not important, but the two tall black 10uF electrolytic
caps are polarised, so it’s important to ensure that the instructions are closely observed when installing
that pair.
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