RIGOL
RX1000 RF Demo Kit Application Note
2. Con tr ol Sw it c h es
After th e soft ware and RX1 000 are succ e ssful ly connected, you can control RX1000 via the
software interface. There are six switches (Sw1, Sw2, Sw3, Sw4, Sw5 and Sw6) on the
software interface and you can click the corresponding switch to control its state.
Sw1: when J12 is connected, connect the external local oscillator signal input from the J12
terminal; when the J12 is disconnected, connect t he internal 1 GHz local oscill ator signal.
Sw2: when J2 is connected, connect the signal input from the J2 terminal; when J2 is
disconnected, a mplify the signal passi ng through the band-pass filter or output it from the
J3 terminal.
Sw3: when J3 and J4 are connected, output signal from J3 or connect the signal input
from the J4 terminal; whe n J3 and J4 a re disconnected, a mplify the signal passing through
the band -pass filtering or the signal input from the J2 terminal.
Sw4: when J5 and J6 are connected, output signal from J5 or connect the signal input
from the J6 terminal; when J5 and J6 are disconnected, perform mixing on the s ignal
passing through the amplifier or the signal input from J4 terminal.
Sw5: when J7 and J8 are connected, output signal from J7 or connect the signal input
from the J8 ter minal; whe n J7 an d J 8 are disconnected, perfor m low-pass filtering on the
signal passing through the mixer or the signal input from the J6 terminal.
Sw6: when J9 is con nected, output signal fr om J9; when J9 is disconnected, adjust the
amplitude of the signal pass ing through the low -pas s filter or the signal input f rom the J8
terminal and then output it via J10.
3. Adjust VGA
Use the mouse to click the text box under the VGA on the software interface and modify the
value (gain code) in it. At this point, you can adjust t he amplitude of the si gnal output from the
J10 terminal (output voltage gain ). The gain code of VGA can be set from 0 to 255.
Output linear voltage gain (
) and gain code (
) satisfy the following relationship:
))1(1( MSBPGVeinierGcAv ×−+××=
Therein,
=0.055744 V/V;
=7.079458 V/V;
When
is from 0 to 127 (low gai n mode),
=0;
When
is from 128 to 255 (high g a i n m ode) ,
=1.