HRO-500 General Coverage Receiver

FREQUENCY RANGE: 5 kHz to 30 MHz in sixty 500 kHz bands continuous coverage.
MODES: Selectable upper or lower sideband, MCW, FSK, AM, CW.
POWER REQUIREMENTS:
A. Pilot lamp switched off
1. 117/234 V A.C 50-6O hertz; 10 watts at 50 mw audio output. 15 watts at 1.5 watts audio output.
2. 12.6 V.D.C ; 2.5 watts (200 ma.) at 50 mw audio output, 6.5 watts (525 ma ) at 1.5 watts audio output
B. Pilot lamps switched on.
1. 117/234 V A.C requires additional 7 watts
2. 12.6 V.D.C. requires additional 59O ma.
CALIBRATION ACCURACY: Within one kHz per 500 kHz band
SYNTHESIZER ACCURACY: Within 250 hertz over entire tuning range when zeroed at 10 MHz.
RESET ACCURACY (Including Visual Error): Within 250 hertz
TUNING DIAL BACKLASH: Less than 50 hertz.
TUNABILITY: Within 2 hertz
MAIN TUNING RATl0: Two speed; 50 kHz/revolution (flywheel) or 10 kHz/revolution
MAIN TUNlNG BANDSPREAD: 1/4" per kilohertz; 12 feet per 500 kHz band.
CALIBRATOR: 50 kHz crystal controlled.
FREQUENCY STABILITY:
A. In room ambients: 300 hertz per hour from point of turn-on to two hours after turn on; better than 100 hertz per day thereafter.
B. With respect to temperature: 50 hertz per degree C.
C. With respect to A C. supply variation: essentially none for +/-27% change.
R.F. INPUT IMPEDANCE: 50 ohm unbalanced (nominal); also separate high impedance unbalanced input for use with random antennas
SENSITIVITY (500 kHz-30 MHz):
A. AM (Nominal): Better than 2.0 uV for 10 db S/N
B. SSB/CW (Nominal): Better than 1.0 uV for 10 db S/N
SENSITIVITY (Fiva kHz-500 kHz): 25-200 uV for 10 db S/N without LF-10 preselector; equal to HF sensitivity when LF-10 preselector is used
SELECTIVITY:
A. 6 db bandwidths available; 500 hertz; 2.5 kHz, 5.0 kHz; 8.0 kHz.
B. Filter Design: six.pole LC type operating at 230 kHz; tunable through 6 kHz range in 500 hertz and 2.5 kHz bandwidth
C. Filter shape factor (Nominal): 2.5:l (6-60 db) in 2.5 kHz bandwidth.
D. Audio filtering provisions incorporated in LF-10 preselector.
HETERODYNE REJECTION FACILITIES: 230 kHz bi-filar notch (REJECTION TUNE control) with +/-10 kHz range around IF passband; minimum rejection capability of 50 db Also, PASSBAND TUNE control (of tunable six-pole filter) permits rejection of adjacent channel Interference without change in frequency of desired signal
IMAGE REJECTION (500 kHz-30 MHz.): Averages 80 db; minimum 50 db
SPURIOUS RESPONSES TO OFF-TUNE EXTERNAL SlGNALS: Minimum 50 db rejection.
INTERNALLY GENERATED SPURIOUS SlGNALS: AII less than 2.0 uV equivalent signals (between 500 kHz and 30 MHz.) except for two discrete responses at 2.75 MHz and 3.0 MHz.
AGC: Time constant; 60 millisecond attack, 3 sec delay AGC merit; average 5 db output change for input increase from la to 100,000 uV
AUDIO FREQUENCY RESPONSE: 100 hertz 5500 hertz within 6 db
AUDIO OUTPUT DISTORTION (Nomlnal): O.5 watts, 3.2%; 1.0 watts, 4.4%; 2.0 watts, less than 10%.
AUDIO HUM: Better than 60 db below maximum output.
AUDIO OUTPUTS: 3.2 ohms to rear panel and front panel headphone jack; 600 ohms balanced with center tap (ground reference or floating) to rear panel.
REMOTE CONTROL PROVISIONS: R.F. Gain; A F. Gain; Receiver Mute; BFO On-Off; Power On-Off.
METERING: Front panel meter calibrated in db above 1.0 uV and from O to S-9 between no-signal and 4O db above 1.0 uv.
AGC THRESHOLD CONTROL: R.F. input attenuator; 0-30 db in nominal 10 db steps.
FRONT PANEL CONTROLS: SYNTHESIZERR TUNE (MHz); PRESELECTOR TUNE; PASSBAND TUNE; REJECTION TUNE; MAIN TUNING (kHz); R.F. GAIN; BANDSWITCH; AGC On-Off-Threshold Control (to 30 dB); FUNCTION Off-Standby-SSB-AM-Calibrate;DIAL LAMPS On-Off; BANDWIDTH 500 hertz-2.5kHz-5.0kHz-8.0kHz; DIAL LOCK; PHASE LOCK Warning.
REAR PANEL CONTROLS: S Meter Zero; Rejection Tune Balance; 117/234 V.A C-12.6 V.D.C. Selector Switch
REAR PANEL OUTPUTS: BFO (230 kHz, 47 ohm, 100 mV); VFO (2980-348O kHz, 100 ohm. 100 mV); synthesizer (500 kHz increments between 7.25 MHz and 32.75 MHz, 330 ohm. 100 mV); 26 MHz oscillator (50 ohm, 100 mV): I.F (50 ohm, output dependent upon signal level); detector (10,0OO ohm, output dependent upon signal level); audio; two spare connectors.
REAR PANEL INPUTS: 50 ohm unbalanced H.F. antenna; high impedance unbalancnd H.F. antenna; low frequency; 117/234 V.A.C.; 12.6 V.D.C.; sidetone oscillator or external audio.
REAR PANEL VOLTAGE OUTPUTS: +12 V.D.C., +11 V.D.C , +10 V.D C , +7.5 V.D.C. regulated, +5 V.D.C. regulated, +1.5 V NPN A.G.C., +9 V PNP A.G.C.
ENVIRONMENTAL CONDITIONS:
A. Ambient operating temperatures: -20 degrees C to +45 degrees C
B. Humidity: to 90%
MTBF: 3820 hours per NAVSHIPS 93820
SIZE: 7 5/8" H, 16 1/2" W 12 3/4" D
WEIGHT: 32 pounds
ALTERNATE CONFIGURATIONS: RMK 5 rack mounting kit for HRO 500 installation (per Mil Std. 189) in 8 3/4 H x 19" W rack space; HRO 500P portable version with built in loudspeaker, self contained rechargeable battery power, and waterproof carrying case
ACCESSORIES: LF-10 (five kHz 500 kHz preselector); HRO 500 TS matching table speaker (7 3/8" H x 5 29/22" W x 12 3/4" D); WPC 5 waterproof carrying case