BR VCF 114 Build Guide

Assembly Instructions

The BR VCF 114 module has no particular build requirements not already covered in the ‘General Build Info' page.

Calibration

1. Power up module and allow to ‘warm up’ for 10 minutes
2. Connect a 100Hz sine wave @ 10V Pk-Pk to Signal input 1. Bandwidth (resonance) to 0%, Signal 1 Level to 100%.
3. Adjust cut-off until output is at a maximum level using an oscilloscope (there are two peaks, either one is fine.
4. Using Pr1, adjust until output is 10V Pk-Pk
5. Apply a CV of 0V to the COF ‘CV In’ input
6. Adjust cut-off until output is at a minimum level (finding notch centre).
7. Apply a CV of 4V to the COF CV In input (should move notch centre up 4 octaves)
8. Change the input frequency until the output is at a minimum level (finding new notch centre). The applied frequency should be 1.6kHz. If not, continue to step 9.
9. Use Pr2 to calibrate at 1.6kHz (see note below)
10. Change the input frequency back to 100Hz
11. Repeat from step 5 until 4V gives a notch centre of 1.6kHz

Note: If the frequency is flat (<1.6kHz), use Pr2 and make the frequency lower (flatter), if above target frequency, use the trimmer to make the frequency even higher, this can be counter-intuitive. You will soon get the feel of how much to increase or decrease the frequency by.

PCB Parts List

*See below for MOTM or MU Potentiometers

Module Parts List

PCB Layout