Atlas 210x, Installation, Operation And Maintenance Manual

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CAUTION
OPERATE THE TRANSCEIVER IN CW MODE FOR ONLY SHORT
PERIODS 0V TIME, JUST LONG ENOUGH TO MAKE THE SWR
MEASUREMENT. CHECK HEAT SINK TEMPERATURE DURING
SWR TESTS, AND IE IT IS GETTING QUITE WARM TO THE
TOUCH, LET THE RIG COOL FOR A FEW MINUTES BEFORE
CONTINUING.
2-15. MICROPHONE CONNECTIONS. The microphone may be either a dynamic or crystal type. A low impedance
Mic. will work, but will require higher setting of the Mic. Gain control, and may require closer speaking. If a
dynamic Mic. is selected, it should preferably be the high impedance type. The choice of microphones is important
for good speech quality, and deserves careful consideration. Select a high quality Mic. with smooth response from
300 to 3000 Hertz or more. An excellent choice is the Shure 404C hand Mic. The plug required for the Mic.
connector is a standard 1/4 inch diameter, 3 conductor type. The tip connection is the keying circuit for press-to-talk,
the ring connection is for the shielded Mic. lead, and the sleeve or barrel is the common ground terminal.
216. VOICE OPERATED TRANSMISSION (VOX). Most press-to talk microphones arc short circuited when the
button is not pressed, if the VOX accessory is installed in the AC console, this feature must be disabled. Refer to
instructions that come with the Mic. Open the case and locate the switch contacts that short the Mic circuit when the
button is not pressed, either disconnect the leads, or bend the contact so they do not make.
2-17. CW KEY. A jack on back of the transceiver is provided for insertion of a standard 1/4 inch diameter 2
conductor phone plug. Connect the CW key to this plug with a 2 conductor cable. The sleeve connection goes to
chassis ground. Keying potential is less than 10 volts, positive, and draws less than 5 milliampères. Any of the
electronic keyers presently on the market will operate satisfactorily.
2-18. REMOTE CW TRANSMIT SWITCH FOR ATLAS TRANSCEIVERS.
The Atlas transceivers have a function switch which provides for switching into the CW Transmit mode. However, it
requires switching from the RLC. to TRANS., and then to the CW position. This procedure is rather awkward, and
the circuit shown below (Figure 2-1) provides a more convenient system.
Figure 2-1. Remote CW Transmit Switch for ATLAS Transceivers
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