Ham radio HF2013DX-A, Инструкция по эксплуатации

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HF2013DX-A HF AMPLIFER INSTRUCTION MANUAL
Page 24 of 37
By pressing MAN or AUTO buttons PA and TRX will return to standard operating mode.
Dividing of bands into segments
Band - MHz 1.8 3.5 7 10 14 18 21 24 28
Width of segment in KHz 30 40 40 50 50 60 100 100 200
TUNING
The HF2013DX-A amplifier is operated in class AB.Thus it’s possible to obtain a maximum
outputpower at an excellent linearity. For this purpose the amplifier has to be tuned very
carefully. The operation of a mistuned PA will cause malfunctions;the increase of grid current
(the G2 will Alarm) and you will have problems with TVI/RFI .
The grid-current is shown as the IA value (maximum value is 1500ma). If you overload the
amplifier the output power increases the grid current at very small rates and the IA will display
the grid current in RED. The safety devices will switch the PA to STBY . You must decrease
the input power.The current of the screen grid is displayed as G2. The amplifier must be set to
have a G2 current less than 50mA and IA must be less than 1500mA.
NOTE: To tune correctly,tune for Maximum RF output with minimum grid current,
such as G2 less than 50mA and IA less than 1500mA.
At currents beyond these values the operating point will be shifted and IM-products (IM
interference) is created through non-linear interaction of two or more co-site transmit signals
whose emitted frequencies combine to create significant harmful.) will be rapidly increased. If
these values are exceeded the PA will activate the safety devices will switch the amplifier to
STBY mode.