This shows you the differences between two versions of the page.
Both sides previous revision Previous revision | Next revision Both sides next revision | ||
playground:alphatross [2020/06/16 15:52] carter |
playground:alphatross [2020/10/15 12:11] jacobs |
||
---|---|---|---|
Line 15: | Line 15: | ||
- To gain control of the source camera: On the joystick unit press "2" then "CAM" to specify the camera. | - To gain control of the source camera: On the joystick unit press "2" then "CAM" to specify the camera. | ||
- Use the joystick and "TELE" or "WIDE" to create a view of interest. | - Use the joystick and "TELE" or "WIDE" to create a view of interest. | ||
- | - If not already present, launch the Alphatross software on the source computer. | + | - If not already present, launch the Alphatross software (Version 6.0) on the source computer. |
- In prompt succession press the "on" buttons for: Water Cooling, Source Power, and He4 Gas. | - In prompt succession press the "on" buttons for: Water Cooling, Source Power, and He4 Gas. | ||
- These actions start a 60 second timer on the RF supply and set initial conditions on the Magnet and Mass Flow Controller. | - These actions start a 60 second timer on the RF supply and set initial conditions on the Magnet and Mass Flow Controller. | ||
Line 24: | Line 24: | ||
- If there is still no plasma try raising the Mass Flow setting to as much as 0.5 SCCM to inspire ignition and then return to 0.35 SCCM. | - If there is still no plasma try raising the Mass Flow setting to as much as 0.5 SCCM to inspire ignition and then return to 0.35 SCCM. | ||
- **This is a pause point for source clean up, can run like this for days, should reduce probe current over time** | - **This is a pause point for source clean up, can run like this for days, should reduce probe current over time** | ||
- | - Monitor the Probe Current, maintain 3 mA +/- 1 mA, and continue raising the Probe Voltage until it reaches 6.5 KV. | + | - Monitor the Probe Current, maintain 3 mA +/- 1 mA, and continue raising the Probe Voltage until it reaches 6 KV. Plasma may not ignite until this point. Return Mass Flow to .35 SCCM if not already there. |
- Set the Oven Voltage to 87 V, wait ten minutes. After 10 minutes the Oven Temp should be around 150 C. | - Set the Oven Voltage to 87 V, wait ten minutes. After 10 minutes the Oven Temp should be around 150 C. | ||
- | - Set the Extractor Voltage to 5.5 KV and the Bias Voltage to a value that gives the desired injection energy less (6.5 + 5.5). Beam yield seems to increase with injection energy above 30 KeV. Suggest trying 41 or 53 KeV settings if pulsing. | + | - Set the Extractor Voltage to 5.5 KV and the Bias Voltage to a value that gives the desired injection energy less (6 + 5.5). Beam yield seems to increase with injection energy above 30 KeV. Suggest trying 41 or 53 KeV settings if pulsing. |
- You may now be able to look at negative beam in the source faraday cup (#7 on the FC meter). Its not clear if this is a useful endeavor. | - You may now be able to look at negative beam in the source faraday cup (#7 on the FC meter). Its not clear if this is a useful endeavor. | ||
- Beam yield will increase as Mass Flow is reduced, expect optimum yield at //around// 0.2 SCCM. | - Beam yield will increase as Mass Flow is reduced, expect optimum yield at //around// 0.2 SCCM. |