Uniden PRO 640XL User Manual

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PRO 640XL

Professional Mobile CB radio

OWNER'S MANUAL

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Welcome!

To the world of sophi sticated, m icro processor con trotted CBradiacommunications. YourUniden
PRO 640XL represents the most advanced mobile radio ever designed tor use in the Citizens
Band Radio Sendee. ItwNI operate on any of the 40 AM, 40 USB or 40 LS8 frequencies authorized
by the Department of Transport and Commur^cations (OOTAC). Your PRO 640 XL features a
superheterodyne dreuit with PHASE LOCKED LOOP techniques to assure precise frequency
control. This radio has been type accepted and certified by the DOTAC.

WARNING

Before transmitting with your transmitter, you must obtain a Department of Transport and
Communications Citizens Band Radio (CBRS) License. Obtain a brochure and a CBRS License
Application Form at your nearest DOTAC office. Mail the completed application form and the
appropriate fee to the Superinterrdent Regulatory of Licensing in the State ot Territory in which
the station will be operated.

CONNECTING THE POWER CORDS

With regard to the connection of the power cords, it may he possible or desirable
to connect the red lead (for negative ground systems) or the black lead (for positive
ground systems) to the ignitionswitchaccessory terminal so that the radio is auto
matically turned off when the ignition switch (key) is turned off.

Alternately, the power lead may be connected to an available terminal on the fuse
block or even to a point in the wiring harness. Care must be taken, however, to
guard against a short circuit condition. When in doubt, please contact your vehi
cle dealer for specific information about your vehicle.

1. MIC GAIN - Adjusts the modulation of the mic for crisp, dear transmission.

2. ANL/NB KEY — You can select Noise Blankerand Automatic Noise Limi

ter orall filters OFF. The ANL/NB helps to reduce harsh background noise caused
by a variety of interference sources.

3. DIM KEY — The dimmer adjusts the front panel lights for optimum viewing.

4. INSTANT CH 9 and 19 — Press these keys to instantly select either channel.

Press again to return to normal 40 channel operation,

5. TXand RX INDICATORS — An LED lights to indicate when the radio is trans
mitting or receiving.

MICROPHONE - TTie operational mode ol the CB is controlled by the push-to-tatk switch on
the mic. Press the switch to activate the transmitter and disable the receiver. Release the switch
to en^le the receiver and disable the transmitter. When transmitting, hold the mic about 2 inches
from your mouth and speak dearly in a normal voice. The mic induded with the PRO 640XL is

a detachsüble, low impedance, dynamic type.

7. S/RF/SWR METER — This LED merer shows the relative strength of the re

ceived signal or the RF output and the Standing Wave Ratio of your antenna,

8. CHANNEL INDICATOR - Displays the channel currently in use.

9. CHANNEL SELECTOR - This switch selects the desired channel tor transmission and

reception. All channels, except channel 9, may be used for communications-between stations
operating under different license. Channel 9 has been reserved by №e DOTAC for emergency
communications involving the immediate safely of individuals or the immediate protection of
property. Channel 9 also may be used to render assistance to a motorist. This is a DOTAC rule
and ap^ies to all operators of CB radios.

10. CLARIFIER — Used to fine tune the receive frequency in USB/LSB modes.

11. RFGAIN — Press this control when strong signa Is are present to improve sig

nal reception sensitivity,

12. SQUELCH - The Squelch control is used to eliminate background noise dur
ing the absence of a transmission. Turn the control fully counterclockwise, then

slowly rotate it back, clockwise until all noise disappears. At this setting any trans

mission must be slightly stronger than the background noise to 'Break Squelch" or

to be heard. Further clockwise rotation will increase the threshold at which a sig

nal will be heard. You can select any level to "Break Squelch"

Controls and Functions

13. VOLUME CONTHOL — Rotate clockwise to turn radio on and to increase

volume.

14. SWR KEY — Press to read the Standing Wave Ratio of your antenna. The

SWR LED wtil light when the 5WR key is pressed.

15. HI CUT KEY — Press to reduce the high frequency response of the receiver.
This key can be used to help eliminate the hiss and pop of weak signal reception.

16. PA KEY — Press this switch to the Pub lie Address mode when an external PA
speaker is connected. When the PA mode is selected, the CB radio will be dis
abled. Adjust the PA output level by rotating the mic gain control.

17. AM/USB/LSB Switch — This switch selects the operating mode of either
Amplitude Modulation, Upper Sideband, or Lower Sideband.

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Pro 640XL Front Panel