To access the "Frequency Modulation" dialog, select "Modulation > Configure > Frequency Modulation" or use the MENU key under "Modulation".
In the upper section of the dialog, you can select the modulation source and activate modulation. The modulation source can be selected independently for the different modulation types and the LF output.
The configuration of the selected external or internal modulation source is performed in the lower section of the menu or in the "Mod Gen" block (internal source only).
These settings affect all modulations which use the same modulation sources.
Activates frequency modulation.
Activation of FM deactivates phase modulation.
Remote command:Selects the source for the FM signal.
You can select the source independently from the different modulation types and the LF output. The configuration of the selected external and/or internal modulation source is performed in the lower section of the dialog or in the "Mod Gen block" (internal source only).
"Internal" | Uses the internal LF generator as modulation signal source for FM. |
"External" | Uses an externally applied modulation signal. The external signal is input via the MOD EXT connector. |
Sets the modulation deviation in Hz.
The maximum deviation depends on the RF frequency and the modulation mode (see data sheet).
Note that you can set a deviation that is too high for a specific RF frequency, or set an RF frequency outside of the adjustable range of the deviation. In both cases, the instrument sets the maximum deviation and displays an error message.
Remote command:Sets the frequency of the LF generator.
This setting affects all analog modulations which use the LF generator as the internal modulation source.
Remote command:Displays the input sensitivity of the externally applied modulation signal at the MOD EXT input in Hz/V.
The modulation deviation entered with "FM Deviation" is achieved with 1 Volt (= Upeak) of the input signal.
Note: The input voltage must not exceed 1.1 Vp otherwise modulation distortions occur.
Starts the adjustment for the FM/PhiM modulator. The option is adjusted concerning DC-offset.
Remote command:(Source "External" only)
Selects the coupling mode (AC or DC) for the externally applied frequence modulation signal.
Note: Coupling for external feed via input MOD EXT can be set independently for all modulations using the external modulation signal.
"AC" | Disconnects the DC voltage component and uses only the AC component of the modulation signal. |
"DC" | Uses the modulation signal with both components, AC and DC. |
(Source "External" only)
Sets the impedance for the external modulation signal, applied at the MOD EXT connector.
You can select 600 Ohm or high (>100 kOhm).
This setting affects all analog modulations which use the external modulation signal.
Remote command:
Imprint | Statement of Privacy | Terms & Conditions | © 2017 ROHDE & SCHWARZ |