The flexible modular concept based on plug-ins (freely selectable) makes the SFM suitable for a wide range of applications. By virtue of the highly compact design, a great number of different configurations can be implemented in a single SFM. Depending on application and configuration, the SFM may be used as : *Multistandard signal generator providing vision and sound modulation signals for up to seven TV standards (B/G, D/K, L/L’, I, M, N, K1) including sound as is required by the dual-carrier method or NICAM-728 as well as an RF upconverter used as a tunable test signal source *RF upconverter with a maximum of three separately settable converters for adjacent-channel and intermodulation measurements *IF modulator comprising several vision/sound modulators to various standards equipped for use in multichannel and multistandard systems The most important features of the SFM are: Generation of TV RF/IF signals (vestigial sideband amplitude modulation) to specified standards All vision and sound modulation parameters variable in wide ranges about standard values Vestigial sideband filter (SAW) and group-delay precorrection can be separately switched on/off Double-sideband test modulator for all IFs between 32 MHz and 46 MHz RF upconverter from 5 MHz to 1000 MHz; suitable for back-channel operation in analog and digital modulation modes Switchover between upper and lower sideband at RF Maximum RF output level from +10 dBm to 0 dBm depending on operating mode (optimum signal-to-noise and signal-to-intermodulation ratio) Non-interrupting level reduction down to -14 dB RF frequency resolution 1 kHz or 1 Hz for precision offset Frequency locking for all oscillators via internal 10 MHz reference frequency or external precision reference frequency RF output impedance 50 Ohm (female N) or optional 75 Ohm (female BNC) AF generator, 30 Hz to 15 kHz, and stereo/dual-sound coder (IRT/Korea) Wideband audio input for BTSC signals up to 120 kHz (standard M) NICAM QPSK modulator with generator for frequencies from 0 Hz to 15 kHz, adjustable BER, PRBS and I/Q test sequences NICAM intercarrier output adjustable between 5 MHz and 9 MHz, digital data/clock inputs/outputs for 728 kbit/s Instrument settings storable in internal memory or on memory card (PCMCIA) System-compatible due to IEC/IEEE-bus and RS-232-C interface Connectors for external keyboard and external monitor