Atlas 210x, Installation, Operation And Maintenance Manual

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SECTION 3
OPERATION
3-1. INTRODUCTION
This section provided instructions for operating the ATLAS 210x/215x transceiver and identifies operating
controls, indicators, and connections. Front panel controls and indicators are shown and described in Figure 3-1.
Rear panel controls and connections are shown and described in Figure 3-2.
3-2. CONTROLS
3-3. POWER SUPPLY ON/OFF, MOBILE OPERATION
The Function Switch has an OFF position which turns off the DC supply to the low current circuits. The high
current circuits (Driver and Power Amplifier) remain connected to the DC supply line, but are automatically
biased off when the low current line is turned off.
3-4. POWER SUPPLY ON/OFF, 220-CS/200PS.
The 220-CS/200-PS supplies have an ON/OFF toggle switch which turns off the AC supply line. This switch
should be used rather than the Function Switch OFF position.
3-5. FUNCTION SWITCH
The first position is the OFF position and is used for mobile operation. The REC. position places the transceiver in
receive mode. Press-to-talk and VOX circuits are operative in this position. TRANS position switches the
transceiver into transmit mode in the event a Mic. without a press-to-talk switch is used, or if you wish to hold-in
transmit mode without having to hold the push-to-talk button down. The CW position is also transmit mode except
that the Mic. Gain control now becomes a Carrier Insertion control and carrier frequency has been shifted about
800 Hertz. (See CW Transmission)
3-6. A. F. GAIN The A. F. GAIN control is used to control audio volume in receive
mode.
3-7. R. F. GAIN
The purpose of the R.F. Gain control is to permit decreasing the between speech noise level, thus providing more
pleasing reception. The AGC system in the ATLAS transceiver has a tremendous dynamic signal range. With full
R.F. Gain, sensitivity will automatically return to maximum in the absence of a signal, accompanied by a natural
increase in background noise.
You may find it annoying to hear the noise level increase every time the person being received pauses between
words or sentences. There are really only two conditions when the R.F. Gain control needs to be on full. One is
when you are scanning the band and want to hear weak as well as strong signals. But, a lot of the time you can
turn the R.F. Gain down a bit, increase the A.F. Gain correspondingly, and realize more pleasing reception.
3-8. BAND SELECTOR AND TUNING DIAL, MODEL 21 Ox
The numbers on the band selector read in MegaHertz for the respective bands: 3.5 for the 80 meter band, 7.0 for
40 meters, etc.
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