OFF-AIR RECEIVER Receiver Topology:
Single-conversion superheterodyne; 300kHz IF; phase-locked I/Q synchronous detector.RF Inputs:
The 75-ohm (F) antenna input connects to the supplied broadband passive AM Loop Antenna. Cable is not included, but up to 100 feet of general-purpose RG-6 CATV coax may be used. A short wire antenna may prove adequate in high-signal areas that suffer minimal interference. A 50-ohm (BNC) high-level input accepts a direct RF sample between 1V and 7V r.m.s. / 3V–20V p-p. Tuning Range:
Tunable via the front-panel menu or the Web interface:
MEASUREMENT PARAMETERSMeasurement Bandwidth:
- 520kHz to 1720kHz in 10kHz steps
- 522kHz to 1719kHz in 9kHz steps Five station-memory pushbutton/Web presets are provided.
Carrier amplitude demodulation extends to 10kHz, ±0.2dB. Measurement is not affected by the user-selectable audio cutoff.Audio Response:
User-selectable “FLAT” response, or restricted in programmable 1kHz steps between 10kHz and 2kHz. De-Emphasis:
A menu command switches-in the NRSC ‘truncated’ 75μs de-emphasis characteristic to the program audio outputs with any restricted audio bandwidth selection.Audio Distortion:
Typically 0.15% THD at 50% carrier modulation; <0.5% at 99% modulation. DISPLAYSModulation Display:
The peak-responding front-panel bargraph readout shows positive and negative modulation peaks simultaneously, with extended persistence of the most recent highest peak value. Measurement resolution is 1% between 50% and 100% (negative) and 50% and 140% (positive) modulation, and 2% between 20% and 50% modulation.RSSI and Noise Display:
The Modulation Display may be switched to show the dBuV level of the incoming carrier (RSSI) and a relative measurement of asynchronous noise. Peak Flashers:
• Absolute-limit flashers are factory-calibrated at –100% and +125% carrier modulation. • A second set of flashers may be programmed by the user to values between –70% and –100%, and +70% and +140%.CONNECTIONSProgram Audio Outputs:
- The active-balanced, rear-panel program audio output (XLR) delivers +4dBu from a 200-ohm resistive source.
- Front-panel headphone jack (¼-inch, TRS).
Open-collector NPN transistor outputs (screw-terminal block) for low signal, program audio loss and overmodulation. Closure polarity is programmable. WEB INTERFACEConnection:
RJ45 jack for remote setup and operation via TCP/IP; DHCP or Static IP with local or remote selectionRemote Monitoring:
Remote Web-based monitoring of off-air audio. Network:
Comprehensive network configuration utility including dynamic DNS and full SNMP support with downloadable MIB file.Alerts:
Supports email and text message services with or without SSLMISCELLANEOUSPower Requirements:
105–130VAC (0.250A Fuse) 210–255VAC (0.125A Fuse), 50/60Hz; 10W..Size and Weight:
1¾”H x 19”W x 7”D (1U); 9 lbs. (shipping).Peak Flashers: Environmental:
0°C – 50°C operating temperature range; 95% non-condensing relative humidity; up to 3000 meters AMSL.