Preferred channels (frequencies)

The TDL450B radio uses an 18 MHz digitally compensated crystal reference oscillator. These emit minimum energy at harmonic frequencies, hence minimizing the effect of harmonic interference on other radio users. However, harmonics of the unit’s reference crystal at 18 MHz can internally interfere with received signals at frequencies that are exact multiples of 18 MHz: 414, 432, 450, and 468 MHz. To minimize the risk for harmonic interference, avoid using these frequencies.