Due to a series of unfortunate events, the surface mounted 1/8 jack was torn off of the board of this Korg Monotron analog synth. I decided to try and tie into the existing onboard speaker to allow the synth to still connect to external speakers or mixer.
I drilled a small hole on the left side to allow wires into the enclosure.
I noted the wires so that if pulled, the solder joints won’t be stressed.
I ran the new line-out red line into the existing solder joint for the onboard speaker.
I desoldered the black line to the onboard speaker. I made a joint between the new line-out black line, the speaker black line, and a new jumper.
All soldered together and bit of heat shrink.
Connected the switch (momentary – normally off) to the original speaker black line solder joint and to the jumper from above.
All put together with the switch mounted and a lesbian adapter on the 1/8 inch male plug end.
Here is a video of the synth put back together and operating. First part of the video (~20 secs) is demoing the momentary switch activating the onboard speaker. The rest is using an external speaker system.
