# 1222 Tuner VCO Module **URL:** \ **Category:** KOSMO MODULES\ **Created:** [January 17, 2020, 5:33pm UTC](https://lookmumnocomputer.discourse.group/t/1222-tuner-vco-module/16 "2020-01-17T17:33:40Z")\ **Posts on this page:** 1\ **Showing post:** 190
**Author:** ![fredrik](https://yyz2.discourse-cdn.com/free1/user_avatar/lookmumnocomputer.discourse.group/fredrik/32/682_2.png) [@fredrik](https://lookmumnocomputer.discourse.group/u/fredrik)\ **Post date:** [April 23, 2020, 9:14pm UTC](https://lookmumnocomputer.discourse.group/t/1222-tuner-vco-module/16/190 "2020-04-23T21:14:29Z")
> [@klausklaerwerk](#): > > i calibrated the 4v think btw, not sure if the other 3 trim-pots do anything atm… Have you checked the voltages on the octave switch (they split the 4 V reference in four parts, so should measure 0, 1, 2, 3, 4 V). For the other pots, this might help: > [@Question about 3340 VCO module](https://lookmumnocomputer.discourse.group/t/noob-question-about-first-diy-vco-module/506/27): > > Performance or DYI/stripboard? If the former, which trimpot are you tweaking – there’s the reference voltage trimmer (RV3) CTorp pointed you to (which is used by the octave selector and the fine tuning knob), but also coarse tuning/centre note (RV6), tracking (RV1), and high frequency adjustment (RV8) and they all do different things. Recommended order afaik is to trim RV3 with a multimeter, then use the octave selector and tuning trimmer (RV6) and knob (RV7) to dial in a mid note (datasheet s… --- _[View the full topic](https://lookmumnocomputer.discourse.group/t/1222-tuner-vco-module/16)._