Modulation Selection; Amplitude Modulation (Am); Frequency Modulation (Fm) - Promax GR-205 Manuel D'instructions

4.5 Modulation selection

The generator can be adjusted with Phase Modulation (PM), FM, AM internal or
external. With the selecting cursor
TYPE key is subsequently pressed you will be able to go through all of the available
combinations of PM, FM and AM, internal and external. The selection can also be
carried out using the revolving selector or the

4.5.1 Amplitude Modulation (AM)

The options are: INTernal at 400Hz, INTernal at 1kHz or EXTernal; if EXTernal
is selected, then the specified modulation frequency range can be applied to the
MODULATION IN/OUT socket.
If AM is selected, then the DEPTH/DEVIATION field automatically shows
DEPTH. With the selection cursor
directly adjusted from the keyboard in %, or can be changed with the rotary control or  
the keys. The modulation depth can be adjusted from 0.5% to 100% in 0.5%
increments.
If the EXTernal modulation is selected, the modulation depth is obtained with a
1V rms sinusoidal wave modulation signal.
If AM is selected, the maximum RF output level is +1.0 dBm. If it has been
adjusted to a higher output level (with AM and/or RF OUT disabled) the warning
message "+ 1 dBm MAX WITH AM ON" will be shown provisionally and the RF OUT
level will be reduced to + 1 dBm. The output level will remain as + 1 dBm when AM
and/or RF OUT are disabled.

4.5.2 Frequency Modulation (FM)

The options are: INTernal at 400Hz, INTernal at 1kHz or EXTernal; if EXTernal
is selected, the specified modulation frequency range can be applied to the
MODULATION IN/OUT socket.
If FM is selected, the DEPTH/DEVIATION field will automatically show Peak
DEViation. With the selection cursor
directly adjusted from the keyboard in kHz, MHz or GHz, or can be changed using the
rotary control or the
0.5 kHz.
If EXTernal modulation is selected, the peak deviation specified is obtained with
a 1V rms sinusoidal wave modulation signal.
The highest value that can be obtained for the peak deviation depends on the
carrier frequency– see the "Specifications" section. If a peak deviation which is greater
that the maximum value for the frequency of the adjusted carrier is entered (using MOD
ON), the warning message "PK. DEV LIMITED BY CARRIER FREQUENCY" will be
shown provisionally, and the peak deviation will change to the maximum allowed for
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in the MODulation field of the main menu, if the

in the DEPTH field, the modulation depth can be

 
keys; the peak deviation can be adjusted with a resolution of
 
keys.
in the PK field. DEV, the peak deviation can be
USER'S MANUAL. GR-205
09/2004