451S-1 Receiver
![[451S-1]](451s11.jpg)
The 451S-1 is a single sideband (SSB) communications receiver with reception of upper and lower sideband, CW, AM, or FSK signals over the frequency range of 0.2 to 30 MHz. The unit is of solid-state design, contained in a desk-top package with built in power supply and speaker. Single knob tuning covers the entire frequency range without bandswitching. A high resolution synthesizer with microprocessor control provides 4 tuning rates down to 10 Hz increments.
High dynamic range along with an operator selectable 20 dB rf input attenuator and passband tuning minimize the effect of adjacent channel interference.
A built-in meter monitors signal strength or line output level. Two operating frequency registers allow rapid change between any two previously selected frequencies. A rear panel connector provides input for an optional keypad to select, store, and recall frequencies.
A rack mount, headphones and DC power cord are available.
451S-1 Features
Fully Synthesized in 10 Hz steps.
General Coverage 0.2 to 30 MHz.
Internal Microprocessor Control.
Solid-State Modular Construction.
SSB/CW and AM Modes.
Passband Tuning.
Built-in AC/DC Power Supply and Speaker.
Digital Frequency Readout.
Frequency coverage ........ 0.2 to 29.99999 MHz
Tuning rate ............... Selectable steps of 10 Hz, 100 Hz,
1 kHz or 1 MHz; 200 steps per revolution
(20 for 1 MHz steps) of tuning knob.
Frequency accuracy ........ Accurate to within 15 Hz when the 39.6 MHz
and 455 kHz oscillators are set within 13 Hz.
Warm-up time is 30 minutes.
Frequency stability ....... Within 1100 Hz (or 120 Hz using optional
oven standard) over the temperature range of
0-50 øC.
Antenna input impedance ... 50 ohms nominal, unbalanced. BNC connector.
Sensitivity ............... (at 1.6 to 30 MHz, not more than antenna input)
0.5 uV for 10 dB S+N/N for SSB and CW using
2.1 kHz filter and 3.5 uV in AM (30% mod 1 kHz)
using 6-kHz filter 0.2 to 1.6 MHz, not more than
1.5 uV SSB/CW and 10,uV AM for above conditions.
Modes of operation ........ A3J (USB or LSB); A3/A3H (AM); A1 (CW), A2 (MCW)
Selectivity ............... Bandwidth
Filter -3dB Min -60 db Max
6.0 6.0 kHz 30.0 kHz
2.1 2.1 kHz 4.4 kHz
360 360 Hz 1250.0 Hz
Optional .................. AC-3811 140 Hz 600 Hz
AC-3812 1.7 kHz 3.4 kHz
AC-3814 3.0 kHz 9.0 kHz
IF and image rejection .... Greater than 60 dB.
Audio outputs ............. Line: 600 ohms balanced with center tap,
adjustable to not less than +12 dB mW.
Local: Not less than 3 watts into 4-ohm load
at 1 kHz, at not more than 10% total harmonic
distortion.
Headphones high or low impedance.
Rear panel speaker jack provided.
Audio frequency response .. Not more than 5 dB var response from 300 Hz
to 2400 Hz
(2.1-kHz filter); 300 Hz to 3000
Hz (6-kHz filter).
Line audio input .......... 600 ohms unbalanced, adjustable.
-20 dB mW input for full audio output.
AGC control ............... Not more than 8 dB audio rise
for signal increase from 2 uV to 100 mV.
AGC operation ............. Attack time: 12 ms nom.
Release time: Fast 400 ms nom.
Slow 1.5 s nom.
Intermodulation ........... 2 signals spaced 20 kHz at a level of -10
distoriton (third dBm each will produce IMD down 50 dB min
order out-of-band) without rf attenuator. (+15 dBm 3rd order
input intercept.)
IF output ................. 455 kHz; -10 dB mW nom at 50 ohms with
5-uV rf input signal.
Mute input ................ Ground to activate receiver,
open circuit to mute.
Primary power ............. 105, 115, 125, 210, 220, 230, 240, 250 V ac
+/-10%, 47 to 63 Hz single phase or 12 to 15
V dc. 100 watts.
Size ...................... 39.4 cm (15.50 in) W, 16.5 cm (6.5 in) H
(w/o feet), 19.1 cm (7.5 in) H (w/feet),
45.7 cm (18.00 in) D.
Weight .................... 12.7 kg (28 pounds).
Environmental
Temperature ............... 0 to 50 øC operation, -20 to 70 øC storage.
Humidity .................. 0 to 95% relative humidity.
Altitude .................. 3,568 m (12,000 ft) operating;
12,190 m (40,000 ft) nonoperating.
Shock ..................... 6-inch drop onto wood bench.
Vibration ................. 2 g, 10 to 33 Hz.
Specifications to change without notice.
AC-3801 Noise Blanker
AC-3811 140-Hz CW Filter
AC-3812 1.7 kHz SSB/RTTY Filter
AC-3814 3 kHz Wide-Band SSB Filter
AC-3807 Internal Oven Standard
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Copyright © Rockwell Collins 1981 & WA3KEY 2000
This Home Page was created by wa3key, Wednesday, June 14, 2000
Most recent revision Wednesday, June 14, 2000