Squareatron 5000
This wiki describes the Oregon Ions programmable ultra-low AM noise rf source.
The Squareatron 5000+ consists of a Squareatron 5000 board, a DAC add-on board, and an aluminium case.
The v1.0 Squareatron board was originally designed by the Oxford Ion Trap Group and can be found here. This project uses the v1.1 version modified by Oregon that can be found here. Hopefully we'll eventually merge these changes.
The DAC add-on board is this repository and the CAD files for the case can be found here.
Shown below are the schematic diagrams for the Squareatron and the DAC tuning board that can be used for reference and will be referred to for the changes that have been made.
Every squareatron has had some modifications made to the squareatron to connect to the DAC tuning board. The squareatron is not ready to use out of the box and a couple adjustments have been made to enable operation. Detailed in this section is all of the changes that have been made.
The squareatron has some initial filter that has to be set. Initially all of the jumpers are populated which results in the board shorting.
The filtering specifications are:
Every board in production has R7 and R8 removed to set FLTA: High and FTLB: Low
Shown in the table below is all of the boards that have finished testing and are ready for use
| Serial Number | Band Pass Filter |
|---|---|
| SQTD+00 | SXBP-29 |
| SQTD+01 | SXBP-29 |
| SQTD+02 | SXBP-29 |
| SQTD+03 | SXBP-29 |
The DAC on board is a the AD5541 16-bit DAC. Initial testing of this device was done by bit-banging TTL pulses on the DIO_RJ45 from Sinara.
