DIY kit
In a Willy Wonka-esque turn of events the schematic for a BJFe pedal was released quietly to the public a couple years ago. The schematic filtered quietly through some DIY builder circles but was largely unknown by fans of the Swedish pedal maker until recently when a collaboration of several people brought a professional PCB and parts kit to market. This guide is meant to serve as a companion piece to the materials supplied with the PCB. It is not meant to be a "paint by numbers" instruction manual but rather a general guide to stuffing a PCB and understanding the way parts fit into one.
1. If you purchased a kit, you will receive the PCB taped to a sheet with the schematic, parts list, and a bill of materials for the contents of the parts envelope.
2. When you open the envelope, carefully sort the components into their separate categories. Check the resistors, caps, diodes, and transistors against the bill of materials. You may have different transistors than those listed in the bill of materials but don't worry, the ones in the kit are perfectly suitable substitutions.
3. When stuffing a PCB, the idea is to work from the shortest components to the tallest ones. This keeps parts from falling out when you flip the board to solder and also makes fitting components easier. If you installed all the tall parts first, you might have a difficult time getting shorter parts into their locations without pliers or other tools. Only simple finger bending will be required if you work from short to tall. Begin by installing the five diodes. Be sure to observe proper polarity alignment and match the stripes on the diodes to the stripes on the PCB.
4. Install the resistors. These are not polarized so they can go either way. Double check the color codes against the legend on the schematic sheet before soldering. Go slowly and only add one resistor at a time if you need to. Since the board is small and rather dense, installing all the resistors at once would make soldering all the leads very tricky.
5. Add the two LEDs. These are polarized so be sure to install the longer leg to the positive pad. Although there is no positive marking on the PCB, you can check the schematic for alignment or note the flat side of the LED outline on the PCB. This is the negative pad and will help you to install the LEDs properly.
6. Add the five electrolytic capacitors. These are polarized to be sure to install them with the proper polarity as marked on the PCB.
7. There are 4 transistors on the PCB. The two at the top right side of the board (1 2n2219a and 1 2n2907) can be installed as the outline indicates. These are part of the clipping circuit. The two 2n2219a transistors in the middle of the board must be aligned properly. You can check the data sheet for the 2n2219a for the proper pinout if you like. If you place one with the flat side down and the leads facing toward you, the leads from left to right will be Collector (C), Base (B), and Emitter (E). Orient the transistor with the leads in the proper pads before soldering. You may wish to socket these transistors so you can try others for different sounds later.
8. Install the two film capacitors and one silver mica capacitors according to the parts list on the schematic sheet. These are not polarized so they can be installed either way. I used Panasonic stacked film caps here although your kit may come with Xicon 'greenies.'
You PCB is now complete.
