Welcome to Part 2 of my ‘Super Breadboard’ post.
In the previous post I showed you the basic layout of the main baseboard which holds the Arduino Development board, the FV-1 development board, the voltage booster, the breadboards and the Input/Output/Bypass box.
For the front panel, I used a piece of 0.9mm thick aluminium measuring 100mm x 250mm which I bought from Bitsbox. After drilling the holes for the pots, switches and MIDI connectors (see below), I bent along one of the long edges to form a 15mm ‘flange’ and drilled three 3mm holes in this and in the baseboard which I could then attach it to using M3 bolts, washers and nuts.
Any guitar pedal will usually have one or more potentiometers (pots) to allow the guitarist to adjust aspects of the pedal’s performance: think of the Drive, Level, Bass, Treble, Delay etc. etc. that you see on typical pedals. I’ve allowed for up to six pots on the front panel and, since different circuits require various different pot resistance values, I wanted to be able to easily swap out the pots. Fortunately, I found that the lugs on the 16mm pots were a perfect fit for the JYK crimp connectors I frequently use for off-board connectors:
This will allow me to easily try different pot values without having to do any soldering to the pots – I can just unplug one pot and plug in another one. The other end of the pot wires have male Dupont connectors to plug straight in to the breaboard:
You’ll notice on the front panel that there are standard 5-pin MIDI IN and OUT connectors – I added these in case I want to experiment with MIDI control – for example, the Blue Nebula pedal has a MIDI IN that allows you to change the patch using a MIDI controller or sequencer. In the earlier eTap2hw development phase I built a couple of echo boxes with MIDI inputs and I had some tiny little (30mm x 20mm) MIDI interface PCBs made up to house the MIDI In and Out circuits so I was able to use one of these in this project. It’s the small red PCB below:
The 4-way Dupont connector carries the +5V and GND wires plus the MIDI TX (transmit or ‘MIDI out’) and MIDI RX (receive or ‘MIDI in’). These would normally be controlled by software running on the Arduino Nano.
So that just about completes the ‘super breadboard’ – now all I have to do is get cracking on designing some exciting new guitar circuit stuff!