Thunder IA Bass

New! Sept 2020: CLICK HERE for detailed information on Active Circuits for Thunder Bass
courtesy of Forum member Purge (David Blair)


This is a diagram of a 1982 Thunder IA bass.

  • The volume and passive tone pots are 500K log
  • The active tone pot is 500K with a centre detent
  • The tone capacitor is 0.022 microfarad Mylar
  • The dual tone and active on/off  switches are DPDT mini toggle switches
1 -This is the ground wire to the bridge.
2 -This wire connects to the centre connection on the D/G pickup, a second black wire runs from there to the centre connection on the E/A pickup
3 -This wire connects to the pickup backplate
4 -This wire connects to the switched earth connection on the jack socket (The power circuit is completed when a jack is inserted)

For clarity white wires are shown as green:

A simplified version

Wire A now runs directly to the body of the active tone pot. Since all the pots and switches are mounted on a metal plate, if any one of the pot or switch bodies is grounded then they all are. There is absolutely no need to solder this wire to the switch bodies as well.

The red and blue wires at point B were soldered to the middle bottom terminal of the active on/off switch in the original wiring diagram, and there was a wire link between the top and bottom left terminals. If these wires are soldered to the top left terminal as shown, the wire link is redundant and can be omitted. (the switch will still function in exactly the same way, but with fewer solder connections to be made)

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