AS3340 VCO /w hard/soft sync, FM modulation

[analogoutput]

Also see this for tuning procedure

As3340 vco tuning problem

I have a specific question when it comes to calibrating the alfa4 vco which uses the as3340 chip. So I’ve been trying to calibrate the module by say turning the coarse tune knob to say 130hz which is around the 10-11 o clock position on the potentiometer, then apply 1v and use the trimmer to adjust it to 261hz. Apply 0v and turn the coarse tune and adjust it back to 130hz. Rinse and repeat. Problem is that on the potentiometer, 130hz is around the 7-8 o clock position so as I do it and go lower,…