I’ve been working towards re-running the Sydney experiment with 2.3 kA of current through the coils. This required completely re-arranging the pieces of the experiment.
A big change was moving the langmuir probe to the same flange as the coils for better alignment.
I’ve been waiting for two weeks for this part from shapeways (thingaverse). It’s a new holder for the langmuir probe:
It holds a ceramic tube like so:
Now the probe is always nicely centered:
I cut down the electron gun for the new arrangement:
I made new ceramic standoffs because the previous ones were poorly crafted. These ones turned out nicely:
Here you can see the electron gun on the left and coils in the center:
I buttoned everything up:
I got the vacuum down to 1.1 millitorr. Not great, but good enough for this experiment.
Tomorrow I will wire up the electrical and run the sydney experiment at full power.
I like the way you iterate the setup – one can always hope that most of the changes are improvements :)
Just a thought: The probe looks quite big compared to the size of the coils. Do you think that it would work to make a smaller one by for example threading a thin wire through a glass pipette?
(The idea is just based on using said pipettes today, I have no clue to whether it would melt or sputter excessively…)