Modulation EN 8.3.5 Modulation Frequency When internal modulation source is selected, press [Mod] > Frequency softkey to set the frequency of the modulating waveform. ⚫ Use the numeric keypad or direction keys and knob to enter the desired frequency values. ⚫ The modulating waveform frequency range is 2mHz to 1MHz, and the default value is 100Hz. Note: This menu will be grayed out and disabled when other modulation sources except the internal modulation source are selected. 8.3.6 Frequency Deviation Frequency deviation is the deviation of the modulating waveform frequency relative to the carrier frequency. Press [Mod] > Deviation softkey to set the FM frequency deviation.
⚫ Frequency deviation must be lower than or equal to the carrier frequency. ⚫ Attempting to set a deviation greater than the carrier frequency will cause the instrument to set the deviation equal to the carrier frequency. ⚫ The sum of frequency deviation and carrier frequency must be lower than or equal When external modulation source is selected, the frequency deviation is controlled by to the sum of the current carrier frequency upper limit and 1kHz. the ±4V signal level on the [FSK/Trig/Sync/Extmod] connector on the rear panel. Positive signal level corresponds to frequency increase and negative signal level corresponds to frequency decrease.
The lower the level, the less offset is generated. For example, if the frequency deviation is set to 1KHz, +4V signal level corresponds to a 1kHz increase of frequency and -4V signal level corresponds to a 1kHz decrease of frequency. 8.4 PM Modulation A modulated waveform consists of a carrier waveform and a modulating waveform. In PM, the carrier phase is varied by the voltage level of the modulating waveform. 8.4.1 Select PM Modulation Press [Mod] > Type > PM softkey to enable PM function. ⚫ When Mod is enabled, Sweep or Burst will be disabled automatically. Copyright © Qingdao Hantek Electronics Co., LTD HDG3000B User manual 41