Setting the K2 dial calibration

Clarifies the intricate process of calibrating the Elecraft K2 dial, addressing common user challenges and lively discussions on the Elecraft reflector. Wilhelm, W3FPR, dissects the K2's PLL synthesizer design, chosen for its low phase noise, kit-friendly duplication, and cost-effective components. The resource emphasizes the critical role of the 4000.000 kHz reference oscillator's accuracy during CAL PLL, CAL FIL, and CAL FCTR functions, noting its dependence on temperature and crystal stability for optimal performance.

Explaining the K2's frequency display, the document reveals it relies on microprocessor-driven look-up tables generated by CAL PLL for VFO values and CAL FIL for BFO values. In SSB and RTTY, these combine, while CW and CWr modes also factor in the sidetone pitch. The author details inherent limitations, such as the 10 Hz increment resolution of the dial and varying PLL step sizes—from 3 Hz on 160 meters to 10 Hz on 10 meters. BFO increments range from 20 to 35 Hz, collectively limiting practical dial accuracy to within 20 Hz with diligent effort, or 30 Hz for a slightly less demanding task.

The guide outlines a four-step calibration procedure: setting the reference oscillator, running CAL PLL, running CAL FIL, and setting all BFOs. It highlights the N6KR Method as a particularly easy and accurate approach, requiring only the K2 and a known frequency source like WWV for zero-beating, eliminating the need for external test equipment.