Atlas 210x, Installation, Operation And Maintenance Manual

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Figure 5-2. Model l0x
5-2 MODEL 10X CRYSTAL OSCILLATOR
The Model lOx oscillator provides for added versatility with the Atlas transceivers by crystal controlling the
operating frequency. Vernier frequency adjustment is provided and a switch selects either crystal or VFO control.
A ten position switch allows selection of up to ten crystal frequencies.
FREQUENCY RANGE WITH MODEL lOx :
Band Range 160M 1800-3000 kHz
75M 3000-5 200 kHz
40M 5800- 10,000kHZ
20M 13,800-14,900kHz
15M 20,600- 21,600kHz
Note: The Model l0x will not operate on the 28 MHz band.
INSTALLATION:
A 9 pin Noval socket on the back of the Atlas transceiver is labeled EXT. OSC. The lOx plugs into this socket. It
will be necessary to remove the two jumper wires plugged in between pins 2 and 3; and pins 5 and 6. Once the
wires have been removed, the transceiver VFO will not function unless the lOx is plugged in and switched to its
VFO position, or the dummy jumper, which is furnished with the lOx , is inserted in the EXT. OSC. socket.
CRYSTAL REQUIREMENTS FOR THE 10X:
The crystal sockets in the lOx are designed for type HC6U crystals with standard .050 inch diameter pins.
Crystals must be ordered for oscillation at parallel resonance with 20 pFshunt capacity. A frequency tolerance of
.0025 per cent at 25 degrees Centigrade is adequate.
Note: The sideband selector switch on the Atlas transceiver changes carrier frequency from 5520 kHz in NORM.
position, to 5523.3 in OPP. position. The Norm. position produces lower sideband operation on 160, 75, and 40
meters, which is normal operation on those amateur bands. On 20 and 15 meters, the transceiver circuitry
automatically produces upper sideband in the NORM. position, which is normal for these bands.
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