Problem
The most popular Version of the Rubidium
Frequenzy Standard FE5680A is tunable over a wide frequency range
(0.5 MHz ... 20 MHz). The frequency adjustment is normally done
by help of a terminal program and a pocket calculator. My software
simplifies this procedure.
This tool supports only versions of the FE5680A which are equiped
with a PIC-microcontroller controlled DDS-board.
| Solution Connect the internal
RS232-Connector of the DDS-board of the FE5680A with the RS232-port
of the PC. On modern PCs a RS232-USB-Adapter may be required. Connect the FE5680A to the power supply. Launch the Rubicon-software. After a click on "Connect" one has to select the
correct COM-port. Then the software connects to the FE5680A and reads
out its momentary configuration. At the big display the value of the
generated frequency is shown. The Hz-
stands
for
the
decimal point. that means the display has a resolution
of 0.01 Hz. Now a new frequency can be selected at the big display (using
the little up/down-arrows). For
convenience some standard frequencies can be selected by the drop down
selector (select a
frequency). But generally every frequency can be selected in 0.01 Hz
increments. The lowest usable frequency
depends on the bandwidth of the analog parts in the FE5680A. Without
modification frequencies down to 0,5 MHz can be generated. The highest
possible frequency is the half of the physics-package frequency. This
is about 25 MHz. The user has to keep this limits in mind. The software
will not really care for this limits. By a click on "Set
Frequency" the FE5680A will be tuned to the new frequency. But
after a power-off-on-cycle the FE5680A would be tuned back to its old
frequency. By a click on "Store", the new frequency will be stored permanently in the FE5680A. Therefor the new value will be stored in the EEPROM of the PIC-microcontroller. This EEPROM has a lifetime of 10 million write-cycles. That means the store-function can be used practically unlimited times. |
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V1.0 (27.06.2014)
First-Light-Version.
