I built this neat little LFO from Frequency Central. I had a need for some smaller LFOs to use in racks built for improvisation, so I got two kits for this Wave Runner and two of another 4hp LFO (post to come). I’d been looking over the Frequency Central modules for a while, but this is the first one I’ve built. Got a full kit from Modular Addict for $40.

The Build

This kit assumes some experience with DIY module building. The instructions are minimal, although the resistors are at least tagged with their values.

The design is simple and effective. All the parts except for the panel jacks and the LED mount on the single PC board. It’s a good quality board and easy to solder. I did find a cramped spot: the trim pot doesn’t quite clear the shrouded header. Be sure to solder the header first!

The panel is aluminum. The jacks and LED are mounted onto the panel, with a rather baroque wiring scheme for grounding everything. The supplied jacks were Thonkiconn, different from those in the build doc, but they work fine. But since they are panel-mounted, all that secures them is the panel nut. The pots are the right angle type, with nothing but their leads holding them to the board. But since the four are close together and in line, the end result is a stable assembly to the panel.

The photo above shows the completed module. Note the wiring from the board to the jacks. I soldered the TL084, but put the PIC in a socket. Notice how the power header cramps the trim pot. I measured the depth from the back of the panel to the bottom edge of the board as 50mm, too deep for some skiffs.

Photo above shows the obverse side. The incoming power does not use ferrite beads or reverse power protection. I would have replaced the 47uf bypass capacitors at the inlet with 10uf, but I’d run out of 10uf electrolytics.

Demonstration Video

Shows all the waveforms and features.