<p>Hey ringworks.<br />
I've seen the clear shaft pots before but never used them. I don't think mouser sells a clear or semi clear knob for those pots... The slide pots are nice but the LED brightness is a little underwhelming. In dim light they would probably look cool.<br />
As far as LED modulation... it's a bit complicated. The pulse is a result of combining 2 oscillators. It's the relationship between the two. The relative tuning of the 2 creates the phase aligning and diverging DRONE/ PULSE effect which the drone lab is built on. This means that putting a light on the controls for each oscillator to monitor that specific OSC wouldn't work. You would only be able to monitor the relationship of 2 OSCs. I think it would make more sense to just have a bank of LEDs which monitor a whole bunch of relationships. For instance one could monitor OSC1&amp;OSC2. Another could be 1&amp;3, another 2&amp;3, 2&amp;4 and so on. There are several possibilities. </p>
<p>In order to use the signal of 2 OSCs to control an LED, you need to create a PWM(pulse width modulation) signal. This is where it gets even more complicated. I put some info on my website here:<br />
http://casperelectronics.com/drone-lab-add-ons/</p>
<p> When you combine the 2 OSCs together you naturally get a PWM signal. The problem is that the signal is only 0-50% duty cycle sweep. you want a 0-100% sweep. You can achieve this by combining an AND and NAND gate signal as shown in the diagram at the link above. I later discovered that AND + NAND is the same as an XOR gate. The good news is that XOR gate ICs are cheap and most commonly comes in quad format.. so you get four XOR gates on one IC. </p>
<p>the output of each XOR gate can be used to control a transistor which will in turn drive an LED. I'll try to get something drawn up soon.
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