The above schematic illustrates how to wire the Panasonic GH1 to the TriggerTrap universal camera trigger.  The TriggerTrap uses an opto couple wired common cathode to isolate and protect the camera from nefarious events.  As the GH1 uses a 2.5mm 4 pole connector, a complete extension cable was sourced from eBay for $6.01 shipping included.  The cable was cut in half, with the unused half making it to the scrap bin for future projects.

The TriggerTrap side employs a 3.5mm 3 pole stereo connector, a suitable connector with a large body was located in the spare connectors bin, the other connectors were sad to see it go but that’s how it is in spare parts land.  The first attempt, as seen below proved to be too fragile, a bit of flexing and the pads pulled off the 3216 size SMD resistors:

Potting in rigid epoxy was considered but the idea was abandoned when the epoxy could not be located, some speculate it ran off with the water based flux, being hydrophilic and whatnot.  The SMD resistors were removed and the second and successful attempt used PTH resistors with small bits of heat shrink tubing but still managed to fit under the hood of the 3.5mm connector body:

The resistor values were selected from available stock, any similar values will also work.  And the final assembly appears to be nothing more than a simple cable, little does anyone know the hidden surprise that awaits beneath: