The above price covers the subsequent set-up:
 | 19" crate, with inserted electronic modules |
| USB interface unit connecting the device with a PC |
| Clock unit allowing for using external 10 MHz reference and for synchronous connection with other generator set-up's |
| Two DDS generator units producing sinusoidal output with frequencies from 0 to 200 MHz with 1 mHz step (32-bit frequency word) and adjustable 14-bit phase offset |
| Each generator is equipped with a switch for digital amplitude modulation and an attenuator for analog modulation. The modulation can be either programmed internally or driven by the external 25-pin input. |
| The generators are programmable as well. They are equipped with 1024 cells for frequency or phase word RAM and can perform frequency or phase sweeps, FSK and PSK modulation and more complex arbitrary time-dependent functions. |
| The system's power supply |
| PC software with source codes |
The controlling software is available in versions for Windows (even for Vista, if God's providence is on our side) and for Linux.
Devices
The panel, shown below, is for activation of selected generator channels and for switching the clock between "External" and built-in "Internal" source.
DDS
Single tone mode
Each generator channel is independently programmable, has it's own memory, digital "Attenuator" and a "Switch" that can quickly block any output signal.
The generator frequency is set in the field "Frequency" of the corresponding DDS panel. The constant phase shift between common clock generator can be set in the "Phase Offset" field (please, do not misunderstand this with imagined trade offset for the F16 fighters that Poland has bought recently).
States of the attenuator, switch and generator work modes can be set by software or through external 25-pin input. The "Control source" field is to chose between these two possibilities.
The "Reset" resets the chosen DDS to its default state.
Memory-assisted generation
Instead of using only one frequency from the "Frequency" field, it is possible to input many frequencies to the generator's memory and use one of available programs to sweep them over.
The memory programmer can be activated in the "Enable RAM" field. A signgle memory cell can contain the 4-byte frequency or a 14-bit phase offset.
The choice is made in the "Select RAM output" field.
If the memory contains the frequency values, the "Phase offset" buffer is filled with the contents of "Phase offset" field. If the memory contains phase shifts, "Phase accumulator" buffer takes the value from the "Frequency" field.
The memory is organized into 4 distinct segments. Each segment has it's own operating mode set in the "Select mode" field described below, the initial and final memory cells' addresses and the RAM data editable in the table, that is displayed after pressing the "Edit RAM" switch.
Generator's modes of operation
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DS -- Direct Switch, the generator uses only the cell with the initial address.
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RU -- Ramp-Up, the generator switches subsequent memory cells, from initial to final, with the elementary step time set in the "Address Ramp Rate" field. After reaching the final cell, the program stops there and generates the last frequency or phase shift that was set in the last memory cell.
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BR -- Bidirectional Ramp, available only in the 0-th memory segment, it swithes cells of this segment from initial to the final address or in opposite direction, depending on the external PS0 line state or to the selection of the profile 0 or 1 from "Active Profile" field.
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CBR -- Continuous Bidirectional Ramp switches the cells of available memory from initial to final address and from final to initial endlessly.
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CR -- Continuous Ramp, switches the cells of available memory from initial to final address again and again in one direction.
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Every generator has it's external control input. It allows for chosing programs (DDS memory segments)-- PS0 and PS1 pins, signal attenuation -- ATTN 0.5-16 and the signal switch state -- SW 0.
