Valon Technology 5009a Operations Manual – Version 1.38
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When the processor receives a command, it then calculates the register values required for each
synthesizer and any other hardware. The ARM processor can make these calculation very
quickly which allows for fast sweep operation by simply setting the start and stop frequencies.
The actual synthesizers are integrated VCO/PLL ICs. The basic synthesizer VCO frequency is
3000MHz to 6000MHz. Subsequent lower frequencies are created by dividing the VCO output by
cascaded digital dividers. Since these dividers are digital, the output frequency will not be a sign
wave and will have high harmonic content.
The output of the divider is amplified by a pre-amplifier that has 4-level of gain control. This,
together with the following digital step attenuator (DSA) provides just over 30dB of level control
in 0.5dB steps. The PA provides additional flat gain to give an output of typ15dBm over
the full frequency range with a typical return loss of 14dB. The pre-amplifier can be turned off
which drops the output level by approximately 50dB providing a low level output at around -
65dBm.
Both synthesizer are locked to a 40MHz internal high-stability, low phase noise, precision analog
compensated VCTCXO. The initial accuracy is better than 2ppm and the stability over
temperature and time is better than 2ppm. Typical initial frequency error is less than 1ppm
while the stability over the -30deg. C. to +70deg. C is less than 0.5ppm. For even better stability
the user can select an external reference in the range of 10MHz to 200MHz. The VCTCXO allows
the user to correct any frequency error to within about 0.010ppm using the Also, the VCTCXO
option allows for electronic frequency control (EFC) by applying a dc tune voltage to the external
reference input.
The 5009 uses a total of five, low-noise, low dropout voltage regulators. Having multiple
separate regulators maximizes the isolation between each synthesizer output and helps improve
close-in phase noise performance. Ultra low noise LDOs are used to power the integrated
PLL/VCO ICs while a 5V LDO is used to power the output power amplifier. The ARM processor
and USB interface have a separate 3V LDOs which isolate digital processor noise from the
synthesizers. The VCTCXO is powered by the synthesizer 1's 3V ultra low noise LDO.
The synthesizer is designed to run from an external 6Vdc power supply capable of supplying the
maximum current draw (see specifications). No special power supply is required and most
switching power supplies will work without degrading the noise performance of the
synthesizers. The maximum input voltage is 8Vdc. Above 9.8V, the synthesizer will shut down.
When using the synthesizer at power supply voltage higher than 6V, it may be necessary to
provide additional heat sinking or cooling depending upon the operating environment maximum
temperature expected. The absolute non-operational maximum input is ± 16V, reverse polarity
protection is provided. The
5009 cannot be powered from the USB port
.
Raising the input voltage to >10V for more than 10sec will reset all of the synthesizers stored
settings to the factory default values.
The 5009 is equipped with a USER PORT which can be use to provide a direct TTL-serial interface
at a default baud rate of 115200. The USER PORT is also used in LIST mode to allow remote