DX-440 OWNER'S MANUAL AM/FM DIRECT ENTRY COMMUNICATIONS RECEIVER RADIO SHACK LIMITED WARRANTY Please read before using this equipment This product is warranted against defects for 90 days from date of purchase from Radio Shack company-owned stores and authorized Radio Shack franchisees and dealers. Within this period, we will repair it without charge for parts and labor. Simply bring your Radio Shack sales slip as proof of purchase date to any Radio Shack store.
CONTENTS Introduction Features Control Locations Choosing a Power Supply............... Preliminary Settings Tuning the Radio Clock Radio Operation Special Tuning Techniques and Controls Special SSB/CW Reception Techniques Using the Shoulder Strap Choosing an Antenna System Grounding Band Allocation The Shortwave Hooby Listening Notes Frequency Conversion ~~~ .............................................•....................................
CONTROL LOCATIONS FEATURES • Wide Tuning Range_lets you receive more stations from more places than ever before. • Supplemental Tuning Controlsallow adjustment for maximum clarity of the selected frequency. • Fast Response LCD-shows you the frequency you select in large, easyto-read numbers. • Dual Function Mode Switch-allows you to display the frequency or the time on the LCD panel. • Direct Acc~ss Keypad-lets you instantly tune in any desired frequency from 87.
CHOOSING A POWER SUPPLY 32. Folding Stand 33. EXTernal Antenna'Jack 34. EXTernal/INTernal Antenna Selector 35. Battery Compartment 36. 9k/10kHz Step SWitch (beneath batteries) 37. Battery Removal Strap You can operate the DX-440 using: that you can lift them easily for replacement.) • Six alkaline D batteries and two AA batteries. • Household AC (with an optional AC adapter) • A 12-Volt DC automotive battery (with an optional DC adapter) INSTALLING BATIERIES 1.
3. Insert six D batteries in the main battery compartment. Position them as shown in the illustration on the back of the radio. For best results, use alkaline batteries such as Radio Shack® Cat. No. 23-550. USING HOUSEHOLD AC USING AN AUTOMOTIVE BATIERY You can power the DX-440 from household AC using an optional AC adapter, Cat. No. 273-1455. Plug the small connector of the adapter into the DC IN 9V socket on the side of the unit. Plug the adapter into a standard household outlet.
PRELIMINARY SETTINGS SETTING THE CLOCK The display shows the time in a 24-hour mode except when you are tuning a station or performing some other operation. The radio uses the 24-hour mode The clock starts when you install the two AA batteries. The display shows CLOCK 0:00. Note: If after installing the two AAbatteries the display does not show CLOCK 0:00, remove the batteries and install them one minutes later.
TUNING THE RADIO ADJUSTING THE ANTENNA Band (Button) Service Frequency Min Max Normal FM broadcasts FM 87.5 108 MHz AM 150 29999 kHz Entire AM Band LW 150 281 kHz Longwave MW 520 1620 kHz Normal AM broadcasts SW 2300 26100 kHz Shortwave in 12 sub-bands Note: Each time you select SW, the radio steps through 12 sub-bands, each band covering as little as 100 kHz to as much as 500 kHz. The sub-bands cor- respond to the wavelengths of each band.
You can select a frequency using four tuning methods: 3. Press [7], [3], [0], [5J. As you press each button, the LCD shows the number. • Direct Tuning 1 2 QQ~Q,. DOD DOD Dr ) 7 • Manual Tuning ~ • Scan Tuning • Memory Tuning 4. Press the EXECUTE button within five seconds. The display shows the frequency and meter band of SW.
6. Adjust the VOLUME and TREBLE/ BASS tone controls for the desired sound level. Note: If you select the FM band and tune to an FM stereo station, move the FM mode switch to STEREO and adjust the BALANCE control for the best stereo headphone reproduction. The built in speaker is monaural. For the best sound result when listening with the built in speaker, do not forget to return the BALANCE control to the mid position. ... ......
b. Rotate the tuning knob in either direction until you reach a desired frequency or station with all five SIGNAL indicators light to obtain best reception. SCAN TUNING LIIII111111IR BALANCE c:::E:IillIIIII LOIIIIIIIIIII>!1 TREBLE Use scan tuning to quickly locate a station or to monitor several stations within a band. c:::E:IillIIIII LO I II I I I I I I I I HI BASS 1. Turn on the radio.
5. Press the SCAN button again to resume upward scanning. When the radio reaches the upper frequency limit of the band, it continues scanning starting again at the lowest frequency on the band. 6. You can fine tune the station using the UP or DOWN buttons. Tune so that the most SIGNAL indicators light for best reception. 7. Adjust the VOLUMEffREBLE/BASS and BALANCE contorls. I MODE MEMORY TUNING STORE IL(_ _I SCAN RECALL DOWN UP L=t=J (L.....
CLOCK RADIO OPERATION 1. Turn on the radio. I I '*' POWER _11111111111""'" I I• mllllllllllill ... ) ( SCAN RECALL I 7 O/SEC 0 0 0 [ 5 6 ------------~~~-i----~~~~~~--~~~~_i 3 2 1 4 SLEEP i -~-'- .~-- 0 0 0 0 TIMER UP )[ I LIGHT 1. Press the TIMER button. The display shows 0:00 and STANDBY for five seconds. ) )L:4=J DOWN Note: If you make no selection while STORE or MEMO flashes, the radio returns to the normal playing mode.
4. When you reach the desired turn on time, press the MODE button to lock the setting. STANDBY stops flashing. In a few seconds, the display reverts to the clock mode and shows the current time. MODE L4=l ( ) RECALL SCAN L=:JI ) UP DOWN Ir r 5. Press the TIMER button once. STANDBY disappears. I TIMER LIGHT 2. If you want fewer than 90 minutes playing time, press the SLEEP button again. Each time you press the button, the playing time reduces by 10 minutes.
SPECIAL TUNING TECHNIQUES AND CONTROLS In addition to the standard tuning operations described previously, use the following controls for special operations. RF GAIN CONTROL This control adjusts the receiver's sensitivity. For shortwave reception, rotate the control to the MAX position. This provides the maximum sensitivity. When you listen to the MW, standard AM band, or LW band, rotate the control only as far as needed to obtain a good signal.
SPECIAL SSB/CW RECEPTION TECHNIQUES Many stations transmit unmodulated telegraph transmissions in the shortwave band. To receive these special Morse code characters, the radio uses a special circuit, a beat-frequency oscill ator, to modify the transmitted signal so that you can hear it. This particular type of telegraph transmission is called Continuous wave (CW) transmission. Many stations transmit voice signals with a suppressed carrier in the single side band.
8. Adjust the CW tone using the BFa PITCH control. BFO PITCH 0 0 0 0 '"...., 9. Reduce strong signals by using the RF GAIN control. This also reduces interference and noise. RF GAIN oe, "" "f' oe, '" 5. Rotate the RF GAIN control to the MAX position. ,"" "" "in {OO USB MIN BFO PITCH MAX RF GAIN OOJ USB 6. Press the AM button to select the AM band. TO RECEIVE SSB VOICE RF GAIN BFO PITCH lSB "" RF GAIN BFO PITCH 4.
USING THE SHOULDER STRAP 8. Rotate the BFO PITCH control to adjust the signal quality. To Attach The Shoulder Strap 0... 0 co, 9. Rotate the RF GAIN control to dampen strong signals. This dm improve signal clarity as well. , "" 1. Insert about five inches of the end of the strap into the strap hanger. ." ." BFC PITCH RF GAIN 0 0 co, Note: Before choosing another band. set the RF GAIN control to MAX, and move the BFO switch to the OUT position.
CHOOSING AN ANTENNA The radio uses a telescoping antenna and an internal ferrite bar antenna for reception of signals between 150 kHz and 1620 kHz. These antennas provide acceptable reception for most situations. However, if you use an external antenna, you can receive more signals, and the signals you receive will be better. FM BAND • Use a set of VHF-TV rabbit ears. Those made for TV/FM coverage can help get better performance on the FM band. • Use a combination TV/FM antenna.
SYSTEM GROUNDING To ensure the best reception, always connect a ground wire to the externai antenna jack. Connect the single wire lead-in to the center terminal of the RCA plug. Connect.a suitable earth ground to the outer terminal of the plug. BAND ALLOCATION A suitable earth ground can be a clamp around a metal water pipe or a copper rod driven several feet into the earth. Radio Shack seils a copper ground rod (Cal. No. 15-530) and the appropriate hardware.
THE SHORTWAVE HOBBY Shortwave listening is a hobby with thousands of participants worldwide. While no special knowledge is required for SWL, you will find your enjoyment increases with experience and special techniques for listening. Random tuning on your DX-440 is a good idea if you've never owned a Communications Receiver before. In this way you can get acquainted with the various bands and the stations that can be heard.
FREQUENCY CONVERSION LISTENING NOTES If you have never tuned a shortwave receiver before, you may be a bit confused by the wide variety of signals that can be heard. To help you find your way around the bands, here is a summary of what to expect. respective countries. Among the stations that are listener favorites worldwide are Radio Japan, the British Broadcasting Company, Israel Radio, Radio Nederland in Holland and Radio Australia. You'll soon discover which stations will be your personal favorites.
COUNTRY LOG The following listing contains some of the more frequently heard stations on shortwave. The stations listed can be heard throughout the North American Continent. All stations operate in English unless otherwise specified. Most of these stations do not broadcast continuously. Obviously, reception will vary on the different frequencies according to the time of day and season of the year.
Buenos Aires, Argentina Programs in spanish Bogota, Colombia Programs in Spanish Ville Louvigny, Luxembourg Warsaw, Poland 6,095 Polskie Radio Wellington, New Zealand 6,105 Radio New Zealand Monte Carlo Monaco 7,140 Trans World Radio Noumea, New Caledonia Programs in French 7,170 Radio Noumea Tirana, Albania 7,300 Radio Tirana Cairo, Egypt 9,475 Radio Cairo Athens, Greece 9,515 Voice of Greece Seoul, South Korea 9,525 Radio Korea 9,530 Spanish Foreign Radio Madrid, Spain Berne, Switzerland 9,535 Swiss Radio
TROUBLESHOOTING The DX-440 is a ruggedly built electronic unit with all parts conservatively rated. However, you should treat it with care; don't subject it to excessively rough handling. You will find it will give you long life enjoyment if kept free from excessive humidity. If you have problems-(we hope you don't),-check the following: FREQUENCY DISPLAY No/incorrect display • Weak microprocessor or radio batteries. • Microprocessor fails to initialize.
CARE AND MAINTENANCE Your DX-440 is an example of superior design and craftsmanship. The following suggestions will help you care for the DX-440 so that you can enjoy it for years. Keep the product dry. If it does get wet, wipe it dry immediately. Liquids might contain minerals that can corrode the electron'lc circuits. Use and store the product only in normal temperature environments. High temperatures can shorten the life of electronic devices, damage batteries, and distort or melt plastic parts.
SPECIFICATIONS Semi conductors: 1 7 8 44 59 7 pc. LSI pes. les pes. FETs pes. Transistors pes. Diodes pes. LEDs Jacks: 1. DC jack for external power (9V) 2. Headphones Jack • 3.5~ for mini stereo headphones. Power sources: 1. For Power when not playing radio: (AA size) penlight battery such as Radio Shack 23-552 or 23-582 (not supplied) for memory/clock back-up (3V). Circuit: FM AM(LW,MW,SW) superheterodyne Dual conversion superheterodyne Frequency range: FM: 87.5MHz - 108MHz Dimension: 11.
ADDENDUM Cat. No. 20-221A DX-440 AM/FM DIRECT ENTRY COMMUNICATIONS RECEIVER The following specifications for sensitivity, image rejection, and selectivity are provided for your reference: Sensitivity : (for 20 dB Signal-to-Noise ratio): AM 150 300 600 1.4 3.1 7.1 15.1 28.1 kHz kHz kHz MHz MHz MHz MHz MHz 1260 560 320 280 4 4 4 4 MV/m MV/m MV/m MV/m 100 40 25 22 0.4 0.4 0.4 0.4 MV/m MV/m MV/m MV/m MV MV MV MV (for 10 dB Signal-to-Noise ratio): SSB 150 300 600 1.4 3.1 7.1 15.1 28.
Image Rejection Ratio: AM/SSB 150 300 600 1.4 31 7.1 151 28.1 kHz kHz kHz MHz MHz MHz MHz MHz 48 65 65 60 60 60 60 60 dB dB dB dB dB dB dB dB FM 875 to 108 MHz 40 dB Selectivity: AM/SSB Wide Narrow IF AM/SSB/CW 1st 2nd FM - 6dB ± 3 ± 2 55.845 450 107 Frequency Stability: Within 1 kHz per hour after 60 minutes warm up.