Midland 79-290 Transceiver Manual

							 
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1.  Be sure that power source, microphone and antenna are connected to the 
proper connectors before going to the next step. 
 
2.  Turn unit on by turning the VOL control clockwise on your transceiver. 
 
3.  Set the VOLUME for a comfortable listening level. 
 
4.  Set the “BD” button to the desired mode (AM/USB/LSB). 
 
5.  Listen to the background noise from the speaker. Turn the SQUELCH control 
slowly clockwise until the noise JUST disappears (no signal should  
  be present). Leave the control at this setting. The SQUELCH is now properly 
adjusted. Do not advance the control too far, or some of the weaker signals 
will not be heard. 
 
6.  Set the CHANNEL switch to the desired channel. 
 
7.  Set the “LOC” button off for maximum RF gain.  
    
8.  Adjust the CLARIFIER control to clarify the SSB signals or to optimize 
AM/WX signals. 
 
OPERATING PROCEDURE TO TRANSMIT 
 
1.  Select the desired channel of transmission. 
 
2.  Set the “MIC” button to off for microphone high power. 
 
3.  If the channel is clear, depress the push-to-talk switch on the microphone and 
speak in a normal voice. 
 
RECEIVING SSB SIGNALS 
 There are 3 types of signals presently used for communications in the Citizens 
Band: AM, USB, and LSB. When the MODE switch on your unit is placed in the 
AM position, only standard double-sideband, full carrier signals will be detected. 
An SSB signal may be recognized while in the AM mode by its characteristic 
‘’Donald Duck’’ sound and the inability of the AM detector to produce an 
intelligible output. The USB and LSB modes will detect upper sideband and 
lower sideband respectively, and standard AM signals. SSB reception differs 
from standard AM reception in that SSB receiver does not require a carrier or 
opposite sideband to produce an intelligible signal. A single-sideband transmitted 
signal consists only of the upper or the lower sideband and no carrier is 
transmitted. The elimination of the carrier from the AM signal helps to eliminate 
the biggest cause of whistles and tones heard on channels which make even 
moderately strong AM signals unreadable. Also, SSB takes only half of an AM 
channel, therefore two SSB conversations will fit into each channel, expanding 
the 40 AM channels to 80 SSB channels. 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. 
  
						

							 
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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 high-
pitched whistle) you will hear the increase in the output tone of the receiver. If 
the incorrect mode is selected, an increase in tone of a whistle applied to the 
transmitter will cause a decrease in the resultant tone from the receiver. 
 
Thus when a voice is used in place of a whistle or tone, in the proper listening 
mode the voice will be received correctly whereas in the incorrect mode, the 
voice will be translated backwards and cannot be made intelligible by the voice 
lock control. When listening to AM transmission, a correct sideband is heard in 
either mode since both upper and lower sideband are received. 
 
Once the desired SSB mode has been selected, frequency adjustment may be 
necessary in order to make the incoming signal intelligible, the CLARIFIER 
control allows the operator to vary frequency above and below the exact-center 
frequency of the received signal. If the sound of the incoming signal is high or 
low pitched, adjust the operation of the CLARIFIER. Consider it as performing 
the same function as a phonograph speed control. When the speed is set too high, 
voices will be high-pitched and if set too low, voices will be low-pitched. Also, 
there is only one correct speed that will make a particular record produce the 
same sound that was recorded. If the record is played on a turntable that rotated in 
the wrong direction (opposite sideband) no amount of speed control 
(CLARIFIER) will produce an intelligible sound. An AM signal received while 
listening in one of the SSB modes will produce a steady tone (carrier) in addition 
to the intelligence, unless the SSB receiver is tuned to exactly the same frequency 
by the CLARIFIER control.  
 
TO RECEIVE WEATHER 
Press the WX button and select the desired channel for your area. The squelch 
and scan functions do not operate in the weather mode. 
 
. 
 
LIMITED WARRANTY.
 
 
Midland Consumer Radio will repair or replace, at its option without charge, any 
Midland Mobile, Base Station, or full power Hand-Held Citizens Band transceiver  
						

							 
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which fails due to a defect in material or workmanship within one year following the 
initial consumer purchase. 
 
This warranty does not include any carrying cases, earphones, or telescoping 
antennas which may be a part of or included with the warranted product, or the cost 
of labor for removal or re-installation of the product in a vehicle or other mounting. 
 
Performance of any obligation under this warranty may be obtained by returning the  
warranteed product, freight prepaid, along with proof of purchase date, to Midland 
Consumer Radio, Warranty Service Department 1670 North Topping, Kansas City, 
Missouri 64120, or to any “ Midland Authorized Warranty Service Station,” or to the 
place of purchase ( if a participating dealer). 
 
Warranty information and the location of the nearest “Midland Authorized Warranty 
Service Station,” may be obtained by writing Midland Consumer Radio, Warranty 
Service Department. 
 
This warranty gives you specific legal rights, and you may also have other rights 
which  vary from state to state. 
 
Note:   The above warranty applies only to merchandise purchased in the United 
States of America or any of the territories or possessions or from a U.S. military 
exchange.  For warranty coverage on merchandise purchased elsewhere, consult 
the supplemental warranty information included with this product or ask your dealer. 
 
 
SERVICE 
 
If it ever becomes necessary to return your unit for service: 
 
Pack the unit in its original box and packing, Improper packing may result in 
damage during shipment. 
 
Include a full description of any problems. Include your telephone number. 
 
You do not need to return accessory items (brackets, screws, power cord, antenna, 
etc.) unless they may be directly related to the problem. 
 
Include a photocopy of the bill of sale or other proof of purchase showing the date 
of sale.  This information must be included before warranty service can be 
considered. 
 
MIDLAND 
RADIO CORPORATION 
 
1120 Clay Street 
North Kansas City, Mo. 64116