Building UralTone effect kits is an easy way to start the soldering hobby. The kits are relatively easy to build, the circuits are quite simple, and they are battery-operated and, safe to try and build. One evening is usually enough to build a finished pedal - a couple of undisturbed building times.

Step 1 - preliminary preparations

If you are an inexperienced builder, learn the secrets of good soldering and the basics of safe working. If you want, you can order some cheap resistors and a piece of Vero board to try soldering components and wires.

Before starting construction, familiarize yourself with the layout picture / build instructions supplied with the kit. This illustrated instruction covers how to build a fuzz effect pedal, but the instruction itself is suitable for all of our effect-building kits as a general guide. However, the pedals may have exceptions to the order of construction, which is mentioned separately, so it is important to read the instructions carefully before starting construction.

Most effects have their own pictorial instructions. You can search for instructions using the "search info section" of the page with the tool under the name of the building series.

Phase 2 - construction site and peace

Reserve enough desk space for the project so that you won't need anything else during the entire project. An unfinished project spread over your table is difficult to pack up and re-sort. A restless construction environment also increases the risk of losing parts.

Have coffee or tea next to you, relax, and focus your thoughts only on this project.

Step 3 - Checking the Kit Parts

UralTone Experimental Fuzz Face Building Kit Unboxed

UralTone Experimental Fuzz Face build kit sorted

Disassemble the parts on the table and sort the parts by type into different piles. Check that all the parts and compare them to the parts list (BOM). Please email us immediately if there are any parts missing The instructions contain pictures of the various components and instructions for identifying them. In the picture series of this article, all parts are also reviewed one by one.

About the identification and placement of parts on the circuit board and the order of work

We have roughly divided the assembly of the effect building kits into three parts: assembling the footswitch plate (point 1 of the instructions), assembling the actual effect circuit board (point 2 of the instructions), and final assembly (point 3 of the instructions). In some cases, necessary adjustments are made to the effect.

Kits built on a circuit board have their own identifier printed on the board for each part. The resistors are labeled R1, R2... or Rled, Rcomp (R = resistor). Capacitors C1, C2... (C = Capacitor) etc. Others are D - diode, TR - transistor, P - potentiometer, IC - integrated circuit chip. The screen printing of the printed circuit board corresponds in appearance to either the external shape of the part or in some cases the symbol of the circuit diagram may be used. The asymmetric shape of the print, added characters, numbers, holes, white bars, etc. specify the correct installation direction of the part.

Parts marked on the PCB (R1, C1, etc.) can be found in the parts list. The fuzz series R1 has a 100 kohm carbon film resistor.

Multipliers are often used in electronic components to shorten the notation. Since the parts are small, in large quantities and large-sized markings cannot be made on them, marking methods aim to indicate the technical values ​​of the part in the shortest possible number of characters/code. Resistors use coefficients:

k=kilo = 1000x
M=Mega = 1000000x.
With capacitors, the comma is moved in the other direction. The basic unit F, Farad is reduced either with the prefix:
µ (or u) = micro = x0.001
n = nano = x0.00001x
p = pico = 0.0000001x.
So 1uF = 1000nF = 1000000pF. Sometimes the coefficient is used as a period, like 4n7 that is the same as 4.7nF. In the part lists, the values ​​of the components are always indicated, depending on the type of part, with a coefficient suitable for the situation.

Step 4 - Start Assembling - Foot Switch PCB.

We start construction from the foot switch pcb. The first part is to install the LED limiting resistor. In the kit, this resistor is labeled Rled.

2.2 kiloOhm carbon film resistor

The resistance value can be read from its colored rings. The resistor in the picture has three red rings. The first two define the value of the first two numbers, in this case the number 2 corresponds to red. The third ring marks the coefficient, the red coefficient is 100. The last ring indicates the tolerance of the resistor, i.e. the accuracy. The example resistor has a value of 22 x100 ohm, i.e. 2200 ohm, i.e. 2.2 kohm (=2K2).

Note: Depending on the circuit, we use either carbon film, carbon composite or metal film resistors. In carbon film and carbon composite, the value is indicated by four colored rings: the first two of these indicate the first two significant values, the third the number of zeros and the fourth the tolerance. With metal film resistors, there is one more color ring, one more reading for the first significant values.

Each kit comes with a color code chart that matches the resistors used in the kit.

Measuring resistance with a multimeter

The resistance values ​​can also be measured. Place the multimeter on the resistance range and measure. Depending on the meter, some meters have automatic range detection and others have to select the measurement range to be used. When looking for a 2.2 kohm resistor, you should choose 20 kOhm as the measurement range.

Folding component legs

Once you have found the right resistor, bend its legs to match the distance between the solder heads on the circuit board. The installation location of the resistor is drawn on the board and marked Rled.

Install the resistor in place, solder the legs and cut the extra connecting wires short. A suitable height is approx. 1mm from the surface of the plate.

Cutting the wires

Continue by cutting the wires for the footswitch PCB. If possible, use wires of the same color as in the instructions (if kit is shipped with different coloured wires). Electricity doesn't care what color wire it runs on, but fixing the device does. Sticking to the right colors also makes troubleshooting easier: each color has its own role: black is ground, red is operating voltage, green is signal in, and blue is signal out. White is the battery ground. As the scale of construction increases, it is even more important to follow the correct colors. Systematization also visually rewards the end result.

An approx. 10 cm piece of different colored connection wires is delivered with the set. Cut 2 x 5cm pieces of each color from these, one 5cm piece of white is enough.

Wire stripping

Strip the ends of the wires, approx. 5mm from the distance. Twist the strands together so that the ends do not fray.

Soldering the wires

Pre-tin the ends of all wires. This step sounds unnecessary and tempting to skip, but it makes the job much easier. The ends of the conductors do not fray, and the soldering becomes significantly better. The joint to be soldered does not need to be heated for a long time, and the pre-soldered wires stay together and do not fray.

Threading to the PCB

Thread the tinned wires onto the board. The wires can also be soldered one at a time, which is easier.

Soldering the wires

Solder the wires. Check that there are no tin bridges or short circuits between the soldering heads

Wire trimming

Cut the excess wire ends short. Also, install the jack wires.

Footswitch installation

Push the footswitch onto the plate. Pay attention to the installation direction of the switch. The switch works electrically when installed either way, but if the installation direction is wrong, the switch will not go into the housing without filing away the anti-rotation bolt.

The foot switch may be a little tight to install depending on the model. Put the circuit board on the table and install the switch to the solder pins. When all nine pins are in their holes, push the switch in. You may need a little force, but don't worry, the switch and PCB will hold.

Footswitch pushed to the PCB

The switch is installed so deep that the solder lugs come clearly through the board. When the switch is in place and straight solder all nine pins.

Complete footswitch PCB without LEDs

The finished PCB looks like this. The led is still not installed, it will only be installed when the footswitch is mounted in the housing. In this way, the installation depth of the led is set correctly.

Step 5 - Assembly continues - Effect circuit board, resistors.

Depending on the series, assembling the PCB may look a little different at this point. In practice, the plot is always the same, the scale and the parts used differ slightly. Depending on the parts of the set, each set is accompanied by instructions on how to identify the part by its appearance and markings. The mechanical installation in the enclosure is almost the same for all the kits in our pedal series.

Always install the smallest/shortest flat mounted parts first (i.e. the resistors and diodes), followed by the plastic capacitors, IC sockets and electrolytic capacitors, and finally the potentiometers. In this way, the parts remain attached to the board's surface when it is turned over for soldering.

With the lowest-first tactic, the first parts to be installed onto the board are resistors R1 - R4 and Rcomp.

R1 100kohm resistor (brown-black-yellow. The last stripe in gold indicates the tolerance of the resistor)

Soldering R1

Cutting the R1 excess legs

R1 soldered to the board

Start with the first resistor in the list, R1. By following the parts list in the kit instructions and interpreting the color ring table, it becomes clear that the resistance rings should be brown (1), black (0) and yellow (x10000).

Note. In some of the series, metal foil resistors are used, where four color rings indicate the resistance value. Carbon film and carbon composite have three rings.

Thread the resistor in place, turn the board, solder, and shorten the legs. The mounting direction of the resistors does not matter, but a good practice is to always install them in the reading direction (left to right) of the color bands, which makes it easier to read the values ​​on the board, e.g. when checking the circuit or replacing a broken part. Built this way, the end result also looks professionally done.

R2, 10k (brown-black-orange)

R3, 330ohm (orange-orange-brown)

R4 1k (brown-black-red)

Rcomp, 2.7k (red-purple-red)

Resistors soldered to the board

Resistors soldered, board from the reverse side

Install resistors R2-4 and Rcomp in the same way. Make sure that the parts are attached to the board's surface, there are no solder bridges between the ends and the connection wires are cut short.

Step 6 - Effect circuit board, ceramic and plastic film capacitors and transistor bases.

Ceramic capacitor C6, C7 - 100pF, marked 101 or 10 and one zero or 100

Ceramic capacitor C5 - 1nF, mark 102 or 10 and two zeros or 1000pF or 1nF

The next parts in height order are the ceramic capacitors and transistor bases.

Ceramic capacitors are marked somewhat in the same way as resistors. The first two readings tell you the value's first two digits. The third reading tells the number of zeros. In a 100pF capacitor, the value is marked as 101, i.e. 10 and one zero. The 1nF capacitor is again marked 102, i.e. 10 and two zeros 1000p = 1nF.

As with resistors, ceramic and plastic capacitors, the mounting direction does not matter. It is still good to install the parts in the same reading direction.

Transistor sockets

Solder the sockets of the transistors. The fuzz can also be assembled without the sockets installed, but we recommend using these, especially if you want to experiment with different transistor options (hence the name Experimental Fuzz Face). Germanium transistors are very sensitive to heat, the use of sockets eliminates the risk of parts breaking when soldering.

Capacitors and sockets soldered

Cut the connection wires short and check the solder joints for short circuits.

Plastic capacitor C3 - 100n / 0.1u

The third place on the height curve is the plastic capacitor C3. As the capacitor type and capacitance increase, labeling practices also change. Possible marking methods include: 100n, 0.1u, 0.1K. Capacitors below 10nF are marked either 4.7n or 4n7, the coefficient replaces the comma. Practices vary between different component manufacturers.

C3 installed

Solder, cut and check. Before installing the electrolytic capacitors, the board looks like this.

Step 7 - Trimmers

Trimmer with markings.

Solder the trimmers P4 - P6 in place. The markings of the trimmers are printed on the housing. The value of these can also be measured with a multimeter (cf. resistors). The resistance is measured on the side of the housing with two connection legs.

Step 8 - Electrolytic Capacitors

Electrolytic capacitor C1 - 2.2uF

Unlike previous components, electrolytic capacitors have a specific mounting direction. The polarity of the capacitors is marked both on the side of the case (white line / 0V = zero volts) and on the connecting wires (long wire - positive, short - negative). Similarly, the positive side of the capacitor is marked on the circuit board. The picture above shows the installation direction of capacitor C1.

Solder the capacitor, cut the connecting wires, and check the solders.

Electrolytic capacitor C2 - 22uF

Electrolytic capacitor C4 - 10uF

Install capacitors C2 and C4. Solder, cut and check.

Step 9 - Transistors

Transistor T1 - BC337

Check the mounting direction of the transistor.

Mount the transistor on the socket

Cut the connecting legs of the transistor to fit under the potentiometers that will be installed later. (If you want, you can solder the sockets to the reverse side of the board, making it easier to change the transistors. Pay attention to the space left under the cover. Install the sockets at a 90 degree angle.)

Check the type of transistor supplied with the kit and install it according to its base connection on the base of the circuit board. Repeat the same with transistor T2.

Circuit board, transistors installed

Step 10 - Installation of Potentiometers

Potentiometer P1 - 5Kohm reverse log

Installing the potentiometer on the board

Solder the potentiometer to the board. Ensure that its connection legs are perpendicular to the PCB and pressed completely against the surface. You should only completely solder one leg first and check the installation position before soldering the rest of the pins.

There are generally three different types of potentiometers: Linear (marked B), logarithmic (marked A) and reverse log type (marked C). Technically, all potentiometers with the same value can be connected to the same place on the circuit. For ease of use, the steepness of the taper varies, so that e.g. the volume control works sensibly when adjusted to different positions.

This labeling convention applies to our potentiometers; some European manufacturers use A and B in reverse.

Potentiometer P3, 250k logarithmic

P1 and P3 soldered

Solder P3 in the same way as P1 and check. The potentiometer must fit in place in such a way that the transistors do not push it askew. If there is no space, fold the transistors slightly to the side.

Fitting the middle pot to the case

Control Pin loose

To prevent rotation, the control pin from the middle potentiometer (P2) must be removed. The UralTone 1590B ready-made case does not have a ready-made hole for this, because the same case is used as a blank for a booster where a slide switch is installed in this position. We didn't want an extra hole in the case, leaving this untouched. The body of the potentiometer is cast aluminum. The guide pin comes off either by cutting with cutters or breaks off by bending it off with needle-nose pliers.

Potentiometers soldered

Potentiometers soldered, bottom of the PCB

Step 11 - Battery Clip

Cutting the battery clip wires to size

Pre-tinning of conductor ends

Threading the wires of the clip through the strain relief holes of the circuit board

Battery clip, threading ends to ends

Battery clip, soldering

The battery clip is easy to install before installing the board in the case:
- First cut the wires of the clip approx. 5cm shorter.
- Strip the ends, twist the strands and pre-tin the ends.
- Thread the wires through the PCB. Push through a lot of wire, so that the wire insulation does not melt when soldering.
- Insert the ends of the wires into the terminals, solder and cut off the excess.

Step 12 - Final assembly or encapsulation.

The assembly of the effect can be started by soldering the five wires of the footswitch board to the effect circuit board.

Wiring between boards

Wiring between boards, soldering wires and shortening ends

Wiring between boards, ready.

You can already screw the nut of the foot switch into place at this stage. The correct installation depth is to screw this as deep as you can with your fingers.

At this stage, if you want, it's a good time to clean the boards from flux residues with isopropanol or substances intended for cleaning circuit boards.

Installation of jacks in the case

Jacks installed


DC jack installation

The installation of the DC jack requires a little dexterity. Install the DC jack in the housing to the so-called lips. The housing dimensions are such that the connector should stay in place. If the opening is too loose, you can use the DC plug inserted into the soldering position as an aid.


Press the circuit board into place. Note the route of the battery clip wires under the jack.

Fasten the nuts


Solder the DC jack

Push the circuit board into place in the holes of the Potentiometers. Screw the nuts of the Potentiometers (your finger is enough at this stage) so that the pots are on the surface of the case. The circuit board should sit with the DC jack at the correct installation height. When the board/jack is in place, solder the jack. You can coax the disc into place when the jack is attached. The legs of the potentiometers give a little. Thread the cable of the battery clip under the jacks as well.


Led polarity

Led mounted on the PCB

Fixing the switch nut

Pushing the LED into the hole in the front plate

Led installation depth

The footswitch's LED is installed simultaneously as the switch is attached to the housing. Install the led mounted in the right direction on the footswitch PCB. The legs' length can recognize the LED's polarity, the bevel on the side of the LED and the shape of the internal elements (see instructions). When the led is on the board, you can bend its connection legs a little so it doesn't fall. Thread the washers of the foot switch into place.

Push the footswitch into place and fasten the nut. When the PCB is properly closed and straight, push the led through the hole on the chassis and solder it on.

Output jack cable

Thread the output wire into place and solder the wire closed.

Output cable soldered

Input cables too

Input cables too

Thread the input cables into place and solder them. Start with the green input wire. This way you avoid the input pin of the jack melting when the white battery ground cable is soldered.

A complete fuzz!

The construction has progressed to the stage where you can install the battery and do the finishing adjustments.

Step 13 - Adjustments and Testing

Adjusting the Fuzz

Some kits, such as the Fuzz example, must be adjusted to work as intended (to sound good). The instructions for the series explain the work in more detail. For the pedal to receive voltage, a plug must be connected to the input. You can immediately test whether the foot switch indicator light is working. If the light does not turn on and off, check the connections, whether the circuit board is powered (measure from the DC jack) and whether the led is installed in the correct direction.

Experiment and test the effect thoroughly. Check the circuit if the device sounds wrong, doesn't work, etc. Make sure the parts are in the right place and installed correctly. Ensure that the cover does not short-circuit the ends of the soldered components that are too long, or that the wires are not pinched between the housing / PCBs, etc. Check the solder joints so there are no short circuits to the adjacent solder pins and no cold joints. Finding faults is a tedious and sometimes boring task, but on the other hand, finding faults and learning from mistakes is very rewarding. They say you learn from mistakes.

Step 14 - Finishing touches

Closing the case

Attaching the rubber feet to the bottom

Installation and alignment of potentiometer knobs

Finished effect

Adding graphics to the case

Adding Velcro to the bottom

The effect is finished when the cover is screwed on, feet are attached to the bottom, and the pots get knobs that match the style. In the series above, a slight elevation is used for the pot knobs so that they are neatly installed at the same height but in such a way that the knob does not rub against the lid of the case.

The easiest way to align the knobs is to set the potentiometers fully counterclockwise and then set the knobs to the desired position and screw them in. For pedals with 3 knobs, it is best to start by attaching the middle knob first.

Real craftsmen can paint fancy graphics on the case.

And it's ready! Enjoy your new pedal build by yourself!