Author Topic: gun scan high/gun scan low issues on SX Five  (Read 3019 times)

Constantin Balica

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gun scan high/gun scan low issues on SX Five
« on: March 09, 2017, 11:19:48 PM »
Hello everybody,

We are now running an SX Five with a LaB6 cathode installed, and playing with it. Beyond the fact that it takes some time to find the best emission current, it keeps giving me the following error when attempting to do gun scan high and I actually can't get a gun scan image. And also, a green cross on the camera monitor, that indicates the mouse click position (marker of the navigator position) got stuck at a certain position and I could not center manually the beam. Needless to say that I am not an experienced user!

The error messages are:
"09:55:35 (E) machlib    GunScan (24056) -> Error status from Column : request deleted".

Can anyone help me with this?

Any comments would be gratefully appreciated!

Cheers,

Costi
« Last Edit: March 10, 2017, 08:19:10 AM by John Donovan »

Gseward

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Re: gun scan high/gun scan low issues on SX Five
« Reply #1 on: March 10, 2017, 08:32:22 PM »
Costi,

I'm not sure what the error means, but I'd start with restarting the software!

I can tell you what my SX100 LaB6/CeB6 (currently) settings are like, if that helps:

When new (March 11 2015) my Iemi was 57 at 15 keV. Set by using the Gun High/Low images. The initial value presumably depends on the tip distance from the cap (3/4 turn, perhaps?).

Over time the value increases:

Once i have a value usually have a routine of:

1) Setting C1=C2=1200.
2)Run Gun Auto.
3)Tweak Iemi to get the highest faraday cup current at C1=C2=1200.
4)repeat 2 and 3 until values are not changing (typically 2 iterations).

I never turn down the Heat if I can avoid it. When not using the instrument I usually only turn off the accelerating voltage to prevent the regulation aperture from getting contaminated, or I leave it with low probe current.


Gareth

Constantin Balica

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Re: gun scan high/gun scan low issues on SX Five
« Reply #2 on: March 13, 2017, 04:03:33 AM »
Gareth,

Thank you very much, and I appreciate your help! You have a very nice curve. I am tweaking Iemi now @ 10kV. I kept C1=C2=1200 all the time.

I will try to rebooting the software and see what happen. It is a little bit annoying not to have a gun high crossover image..

my best,

Costi