UralTone Soviet Fuzz assembly instructions
UralTone Soviet Fuzz assembly instructions
[product ids="32340"]UralTone Soviet FF GT308- BOM - Bill of materials
Check all the parts
Always check first that all parts are included in the delivery. If you find any problems please contact us by email or through the "contact us" form on the pages. Note that the components may look slightly different than in the photos. Also, note that the voltage specs of the parts may be higher than what is listed. Read all the notes at BOM (bill of material) carefully.
Building the pedal
Follow the order in which the images below are assembled. We try to keep component manufacturers and types the same, but sometimes we have to change the manufacturer or model of a part due to poor availability. So if a part is a slightly different color or higher voltage rating, all is good, each component has the required values marked on the side of the part.
Start building from the footswitch. The front resistor of the LED is soldered first. This resistor is packaged separately in a bag of other parts of the hardware set.
Press the foot switch onto the FS board. Note the installation direction, the hole in the threaded part will come up. The soldering heads on the plate may be narrow, so press the switch with sufficient force. The circuit board and switch will not get hurt!
Cut 5cm lengths from the cord provided with the kit. Peel the insulation about 3mm apart, twist the strands together, and pre-solder the stripped wire ends.
NOTE: The LED will not be installed at this time!
UralTone Kouvola fuzz effect circuit board: The locations of all parts with their part numbers (designator) are printed on the board. C=capacitor, R=resistor, Q= transistor, D=diode etc. The values or types of parts corresponding to the designator can be found in the parts list provided with the kit.
It is a good idea to start with low / smaller parts, so that the parts are pressed against the surface of the pcb when they are soldered to the board and the board is turned over on a table or similar surface. Start by populating the resistors on a pcb. Resistors are marked R1, R2, etc. Resistor values are marked with colored rings. To interpret these, see the table provided with the kit. The correct values can also be measured or compared to the color rings in the image above. It doesn't matter the direction in which the resistors are installed, but for readability, it's a good idea to install them in the same direction, depending on the printing on the disc.
Solder diode D1 to pcb. Note the mounting positition. Diode has tripe printed on the end of the package. The pcb has same figure silk screened.
Solder the trimmer RV1.
Solder the ceramic capacitor C4. The values of the ceramic capacitors are denoted so that the first two digits indicate the value of the first two digits. The third indicates the number of zeros. For example, 471 is 470pF, 472 is 4700pF, or 4.7nF. The installation direction of these parts does not matter.
Solder the electrolytic capacitors. The kit may be delivered either with axial or radial capacitors. All of these have polarity to follow. Axial capacitors has grooved end on positive terminal. This is aligned according the silkscreen. Radial capacitors has stripe on negative terminal side. On pcb has printed plus sign on opposite end of striped end.
Solder the transistors. These are selected and marked by parts numbering (Q1 is marked 1...) Germanium transistors does not tolerate heat that much so be quick when soldering.
Note: Silk screen on the pcb has error and the dot is printed on right side. Mount transistors dot pointing to left like in pictures above.
Same as previous picture for different angle. Note the transistor which are lifted a bit from the board level. This prevents heat to grawl in part while soldering. Do not leave transistor legs too long. The package of the transistor carries signal/voltage and may short circuit.
Solder the potentiometers. It's good practice to solder only the mid pin first and check the proper fitting of part. When it's properly fitted, solder rest of the pins.
Solder the footswitch board made at the beginning and the battery clip to the main pcb. The wires of the battery clip are threaded through the pcb and soldered to the pads. This results in strain relief on the conductor. The wires of the clip can be shortened slightly, approx. 5cm. The appropriate length of cord can be measured by temporarily placing the parts inside the case.
Install the Jacks in the case. Not not overtighten, since you need to rotate them when the wires are soldered.
Insert the DC jack into the mounting hole.
Slide the LED into place. Note the polarity of the LED. The shorter leg / chamfered LED is marked on the pcb. When viewed vertically (wires up), the beveled side / shorter coupling foot comes to the left. Washers are placed in the threaded portion of the footswitch to await installation.
Install the board in the case. When installing the effect pcb, care must be taken that the DC jack does not fall out of place. (This can be prevented with a non-powered DC cable or plug). Install the front panel. Tighten the nuts with your fingers and fit the plate neatly into place. When everything sits as desired, soldr the DC jacket closed. The LED is installed by pushing it through the front panel and soldering it.
Solder the jacks. The solder lugs of the interior jacket are pressed in before soldering. The jacks can always be rotated for soldering. After soldering, the jacket is twisted for the next wire. Start soldering as seen from the lower lug, so the wired wires move deeper into the housing and are not in front when the next wires are soldered in place.
The UralTone effect kits are delivered with two different types of input jacks. Please refer how to solder instructions found here: https://en.uraltone.com/blog/input-jack/
Attach the potentiometer knobs and install a 9V battery. Now you are ready to take your guitar / bass / synth and test how does it sounds. If all works, we still have to bias transistors to work as designed.
You'll need a multimeter and a small precision screwdriver. Adjust the front panel potentiometers to full. Connect plug to input jack and let the device warm and stabilize for some time.
Insert the black measuring probe into the screw hole on the bottom of the effect housing (this is ground). Measure the voltage at test point on the mid pin of the trimmer. Adjust the trimmer until the voltage is 6-8 Vdc.
The values given are recommendations. Always listen and make sure pedal sounds as good as possible. If you pedal sounds best with some other voltages, that's fine, sound quality is the most important thing!