An excellent companion to virtually any audio processing system or transmitter exciter on the market, the digitally synthesized CRL Systems SG-800A FM Stereo Generator produces laboratory grade composite signals even with the complex wave forms produced by large amounts of competitive audio processing. The digital design of the SG-800A provides absolute stability and maintenance free composite/pilot synchronization.
- 10 Segment Audio Level Display
- Digitally Generated Carrier
- Exclusive Pulse Amplitude Modulator
- Adjustment Free Pilot Phasing
- Two SCA/RDS Input Ports
- Balanced, Active Differential Program Input Ports
- Low Impedance – High Drive Capable Output
- 7th Order Elliptic 15kHz Low-pass Filter with Delay
- Equalization (Optional OPT-1 Filter Card)
- Protection Limiter to Prevent Over Modulation (Optional OPT-1 Card)
- User Selectable Pre-emphasis of 50�s, 75�s, or flat (Optional OPT-1 Card)
- Easy Audio Level Adjustment
To aid the user in properly setting the audio input level, each channel has a separate 10 segment peak-reading LED level meter with a range from 10 to 100 percent. The LED indicator reading equates to a peak modulation value when the SG-800A is calibrated to the FM exciter.
Digitally Synthesized Carrier
To provide a low distortion signal with excellent stability, and to reduce spurious signals, the SG-800A uses a digitally synthesized carrier generator. This method eliminates all significant generator harmonics and provides an extremely clean baseband composite output.
Pulse Amplitude Modulator
Digital generation of the 38 kHz stereo subcarrier in the SG-800A is done by a pulse amplitude modulator (PAM). The PAM switching network uses highly linear switching modules to produce an approximation of a sine wave very low in even and odd order harmonics. A digital approach to subcarrier generation makes possible absolute phase locking of the subcarrier and pilot signal so that there is never a need to adjust pilot phasing.
Two SCA/RDS Input Ports
Dual sub-channel input ports are provided to utilize one or two sub-carrier generators with the SG-800A Stereo Generator. The signals, such as those used in SCA or RDS service, are combined with the composite output signal in a unity gain circuit. A Pilot Tone sample port is also provided as a reference for an RDS generator.
Balanced, Active, Differential Program Input Ports
Provide for rejection of common mode distortion. Internal jumpers configure the inputs for 600 ohm termination or high impedance bridging interconnection to a wide variety of electronic equipment.
Low Impedance, High Drive Outputs
The SG-800A utilizes a high current output amplifier for improved composite output drive. This allows the stereo generator to drive low impedance loads and feed cable lengths up to 300 meters (50 ohm coaxial cable).
7th Order Elliptical 15kHz Low-Pass Filter with Protection Limiting
(Optional OPT-1 Filter Card)
Includes overshoot correction and delay equalization to allow maximum stereo separation while offering pilot and subcarrier protection surpassing most existing stereo generators. A built-in hard limiter circuit protects against over modulation.
User Selectable Pre-Emphasis
(On OPT-1 Card)
Internal jumpers set the amount of audio pre-emphasis to either 50�s, 75 �s, or flat. The feature allows the SG-800A to be used for a variety of signal transmission applications.