The Dome filter part selection
Here are R and C values i have used for the dome filter , as specified by JH documention.
Quadrature VCO ouptuts
I have added a little buffer amplifier with a gain of 2.5 to output internal quadrature VCO triangle waveforms (0 and 90° phase ).
Schematic of the dual buffer for the Quadrature VCO ouptuts (gif)
Buffers inputs ( J5 , J7 ) are wired to the JH-FS1A mainboard as described on the picture bellow
How it look in reality...
and scope view of signal available on the 0° and 90° output jacks
Quadrature VCO triangle outputs in X/Y mode
Download Papareil Synth Lab's front panel design for the JH-FS1A MOTM 2x5U size (FPD file)
and the real one
The quadrature VCO outputs extension board was not yet installed when i took pictures...