It is the Music From Outer Space (MFOS) Sound Lab Mini Synth Mark II, an analog synth from the great late Ray Wilson. There is quite a lot of involved soldering – though I did do more soldering back in the days when I was constructing the Electronics Australia Playmaster series of pre-/subwoofer/stereo amps, but it actually looks like the wiring to all the pots/plugs may be the killer.
I decided to buy this after going down an analog synth hole in Youtube recently (spurred on by the excellent DIY synth videos by Moritz Klein). I can’t wait to get started, but will have to ease myself into it by building the power supply first. Eventually I’ll have to build a housing for it, and am on the fence between staining plywood or using walnut hobby board. A great project though for these socially isolated times!
I had a sizable pile of infra-red RGB controllers that came with every RGB LED strip I’ve ever purchased. Still, one was never around when I needed it, and the transmission range was so small that I’d have to move closer to the LED strip to change the color anyway. Finally, there were really only a few unique colors – most looked the same as the next. I decided to instead replace the RGB LED PWM generator with an ESP8266 (as a NodeMCU) that I could control via a web interface from my phone.
Given that I had a couple of RGB signal boosters, I did not need to use high-current MOSFET transistors to drive my 15-foot LED strips, and instead I chose to use 2N2222 NPN transistors because I have an ample amount of them. The RGB LEDs in the strips are SMD 5050s, which are rated at 60 mA per LED channel. The strips come with their own resistors, so all that’s needed is to drive the NPN transistor with the correct base current.
To have the transistor act as a PWM switch, the recommendation is to have the collector-emitter current be 15-times that of the base current, meaning my base current would be (current per LED / 15) = (60 / 15) = 4 mA, which the ESP8266 can handle (the limit is 12 mA per pin). The voltage output of a ESP8266 GPIO pin is 3.3 volts, and the voltage drop across the transistor is ~ 0.7 volts, so given this and Ohms law, I could determine the base resistor to use: V = IR, R = V/I, R = (ESP8266 voltage – transistor drop)/ 4mA = (3.3 – 0.7/ 0.004) = 650 Ohms. The closest resistance value to this is 680 Ohms, so I went with that.
Schematic for circuitBreadboard layoutThe final resultThe web interface for controlling the color
I follow DHH (creator or Ruby on Rails, among other things) on Twitter and he always has great insights on tech. I found myself one day reading the Basecamp (of which he is a co-founder) employee handbook, thinking it was going to be something like the one from Valve, but to me this was so much more. I stopped reading every now and then to think “wow, can work life possibly be like this?” and was left wondering how I as a small cog in a corporate machine could hope to make any changes like this.
Then COVID-19 happened, and the very corporate environment that I used to work in shifted to something closer to their ideals, but honestly still far, far away. I wondered what other advice Basecamp had regarding working from home, and found their book “REMOTE: Office not required“. It’s a great read at only a few hours, is packed with information, and helped me out with adapting to working from home. From it, I’m going to be reading at least one more book: “On Writing Well” (my reading list is just getting out of control, though not nearly as bad as my Steam games backlog) and I’m going to bring my 32-inch 4k monitor at work back home – I don’t know what sort of crazy I was thinking by leaving it there.
