Hi! I want to share my successful build of a Nigel's Speed Controller, and share some PCB design files for the faceplate I made.
The front panel is an ENIG PCB, black, with lettering and graphics in gold. Bottom-firing orange LEDs light up the power and speed indicators. The selector knob points at the speed adjustment wheel for that speed, and the speed lights up with a warm orange glow. Bakelite knobs complete the retro look and feel.
Before anyone asks, yes, the earth-grounds for the input and output connectors are bolted to the chassis!
I installed solid-copper heat-spreaders to the amplifier chips to enhance their thermal performance. These adapter plates are normally used to mount TO-3P transistors into Pioneer receivers, which use a type of-large-format transistor with a large copper heat-spreader. (I also make MT-200 and TO-3 versions of this.) The chip is SMD soldered to the heat-spreader, increasing the copper mass beneath the silicon die. Heat is moved away from the die quicker than mounting straight to aluminum. (Aluminum conducts heat at only half the speed of copper.)
Don't do what I've done here! With the holes for each control. It was a PITA. Suggest instead cutting out a big hole in the panel with a scroll-saw, jigsaw, however you like to cut 1/4" aluminum. You can use a sacrificial PCB as a template to drill the holes and make the cutout. Tape the PCB to the front panel exactly where you want it. Drill (6) 2.5mm holes and tap M3x0.5. There are dotted cut-out lines printed on the PCB to guide your blade.
A closer view of those heat-spreaders.
I'm using a regular plug here instead of an IEC outlet. My friend promises never to plug anything weird into it, other than a turntable.
Parts:
Chassis: Tokban Audio 3209 320*90*311mm (Search on Aliexpress)
Knobs: (4) Knob Davies Molding 1475
(1) Davies Molding 2150-V
LEDs: (7) KingBright AA3528SECKT09 Orange bottom-firing
M3 6mm Button-head hex screws.
https://www.mcmaster.com/91239A111/The PCB files:
I used JLCPCB, but anywhere that does good ENIG boards is fine! I designed it in EAGLE 7.5, here are the design files. There are GERBERS you can just have the PCB made with, and there are EAGLEs, you can edit the board if you like.
https://www.dropbox.com/scl/fo/koz0h3r1f0q9ghf2k3xhw/ADmdJUnrGRJJmqfe3o6uHD8?rlkey=7zt2pdbxj8oibfu8uw3fk06bz&dl=0I've taken off my logo "Hoppe's Head" and replaced it with a simple, circular back-lit power indicator. You might like to get creative with your own design.
