Hook up the electronics

  1. Let's hook it all up! Start with the magnetic cartridge, hooking it up to the connectors at the end of the tonearm. Keep the cover on, that needle is infinitely sensitive!
  2. Next up, drop the Pi in to the electronics case, alongside the power supply and the stepper driver. Screw them in place in each corner
  3. Push the SD-card into the Pi from the outside of the case.
  4. Pull three cables from the 3-step switch, through the hole just over the SD-hole in the casing, and put the outer two cables onto the Pi pins 11 and 13. Place the middle cable onto Pi ground (pin 9 for example).
  5. Next up, let's hook up the Pi to the power supply. Grab one of the 5v connectors, push it into pins 4 and 6, careful not to mix up ground (pin 4) and 5v (pin 6).
  6. So the next step is to connect the stepper driver to the 5v rail. You really don't want to use anything over 5v to drive that bastard, or else it'll run hot and melt your PLA pulley! So take two 5v cables from the power supply, and place them into logic and . Keep them separate, the stepper driver is a bit stupid, and can't run both logic and stepper from the jumper. Grab a ground from the power supply, and connect it to the stepper driver ground.
  7. Connect the stepper to the Pi like so: Stepper A1 to GPIO pin 20, A2 to 16, B1 to 26, B2 to 19, enable A to 21 and enable B to 13. Do note that I've switched from pin notation to GPIO notation here!
  8. Take the amplifier, put it down over the Pi, and screw it in through its red port.
  9. Hook up the amplifier to the 12v rail and ground from the power supply.
  10. Pull the cable from the tone-arm out through its dedicated hole. Put the RCA plugs onto the cables, and keep an eye out for not mixing up which ground belongs to which. I'm using boat terminology, so red is left (port), and green is right (starboard). If you're using other cables, red is right, and white is left.
  11. Keep an eye on the Pi USB ports, so they're not touching the card above. If they do, put a piece of paper or likewise between them, so it doesn't short, and make the Pi's life short.
  12. Plug your stepper cable into the stepper motor, and connect the stepper coils A1, A2, B1, B2 to the corresponding stepper driver A1, A2, B1, B2.
  13. Plug in the power supply to the mains, and all should fire up! Or go up in smokes if you're unlucky. Do note that you've obviously got a bit of exposed 230/110v in the PSU, so don't get a shock from that, and don't blame me if you do!
  14. Last but not least, lock the tonearm in place in the rest, flip the turntable onto its left side, and place the electronics box in place over the stepper motor. It'll be a bit fidgety getting the self-tapping screws to grip onto the chopping block, so be careful not to wear the screw-heads out!