User manual MIDLAND 79-290

[. . . ] TABLE OF CONTENTS Specifications Installation Location Mounting the Radio Ignition Noise Interference Antenna Tuning the Antenna for Optimum SWR External Speaker Operation Control and Indicators Front Panel Real Panel Operating Procedure to Receive Operating Procedure to Transmit Receiving SSB signals SPECIFICATIONS (CB) GENERAL Channels Frequency Range Frequency Control Frequency Tolerance Frequency Stability 40 CH/AM//USB/LSB (120 ch. total) 26. 965 + 27. 405 CB Phase Lock Loop (PLL) synthesizer 0. 005% 0. 001% Operating Temperature Range Microphone Input Voltage -20° C to + 50° C Plug-in dynamic; with push-to-talk switch 13. 8 V DC nominal, 15. 9 max. , 11. 2 V min ( negative ground) and coi 2 TRANSMITTER Power Output AM 4 Watts SSB 12 Watts PEP AM/SSB SSB 3rd order, more than -25 dB 5th order, more than -35 dB 55 dB 50 dB AM 350 to 2500 Hz Modulation Intermodulation Distortion SSB Carrier Suppression Unwanted Sideband Frequency Response RECEIVER Sensitivity . 50 uv AM . 25 uv SSB AM/FM: 10. 695 MHz 1st IF, 455 kHZ 2nd SSB: 10. 695 MHz IF Frequency IF Adjacent-Channel Rejection Automatic Gain Control (AGC) Squelch Adjustable; 60 dB AM/SSB Less than 10 dB change in audio output for inputs from 10 to 100. 000 microvolts threshold <. 50 uv tight 1000 uv 4 watts into 8 ohms Audio Output Power WEATHER RECEIVER Channels 1 162. 550 5 162. 450 8 161. 550 2 162. 400 6 162. 500 9 161. 775 3 162. 475 7 162. 525 10 163. 275 4 162. 425 *All specifications subject to change without notice 3 Your new Midland model 79-290 represents cutting edge technology in the communications field. From its high tech detachable control panel to finned cast almuinum transmitter heatsink it incorporates features found on no other CB. These features include full surface mount technoloy, fiberglass printed circuit board, dual power output stage, and a digital information screen using a black matrix LCD (liquid crystal display). [. . . ] Press this button for instant selection of highway channel 19. The channel or frequency display flashes channel 19 when instant channel 19 is selected. The rotary channel selector is bypassed when the CH19 button is activated. Press the CH 19 button again to return to normal channel selection. 7 6. Press this button for instant selection of the NOAA weather bureau or Canadian receiver. Select the proper channel, with the rotary channel selector, for your area. It is normal to hear the same information on more than one channel, select the channel with best sound. To return to CB operation, push the WX button again. LCD indicator showing which memory channel has been selected (1 - 4). This indicator on the LCD screen will be illuminated when the unit has been set in TX mode. This switch selects any one of the forty Citizens Band channels desired. The selected channel or frequency appears on the LCD readout. The channel selector is bypassed and will not operate when instant channel 9 or 19 has been selected. These 4 buttons are used to enter and select the 4 memory channels. To set channels in the memory , select the desired channel for M1, press and hold the "M1" button until a second beep is heard and the memory channel indicator lights. Your selected channel is now entered at M1. Repeat the above operation for M2 through M4. To recall a memory channel just press the the "M" button. This button is used to select the LSB, USB, AM, mode of operation. Unless the station with which communication is desired is equipped with SSB, the AM mode is normally used. The band "BD" button changes the mode of operation of both transmitter and receiver simultaneously. Turn to `'Receiving SSB signals'' for a further explanation of single sideband. [. . . ] The reduction in channel space required also helps in the receiver because only half of the noise and interference can be received with 100% of the SSB signal. 11 An SSB signal may be received only when the listening receiver is functioning in the same mode. In other words, an upper sideband signal (USB) may be made intelligible only if the receiver is functioning in the USB position. If a lower sideband (LSB) signal is heard when the receiver is in the USB mode, no amount of tuning will make the signal intelligible. The reason for this may be understood if you consider that when modulation is applied to the transmitter's microphone in the USB mode, the transmitter's output frequency is increased whereas in the LSB mode the transmitter's output frequency is decreased. The result in listening to the receiver is that when the "BD" is in the proper mode (either USB, or LSB), a true reproduction of single tone of modulation will result, and if the tone is increased in frequency (such as a low-pitched whistle or a highpitched whistle) you will hear the increase in the output tone of the receiver. [. . . ]