How do you feel about the new polling feature?

Well, I tried. After carefully calibrating the strong and normal flash currents (and this time remembering the 0.6 ohm calibration resistor), it still produces no beam. Think I'll take the weekend off, but after that: new emitter time!

This is why I ❤️ the interwebs. Three clicks and an exact replacement is on the way. In the meantime I devised a highly technical alternative cooling scheme.

Still, I'm very grateful that this yak came to visit while I was actively working on the scope and not (say) when she was baking overnight. So tune in next time for the exciting adventures of Captain Maintenance and the Electron Emitter Replacement from Hell.

And so, my friends, this is what a yak infestation looks like. Now I get to repair (or replace) the chiller so I can power up the scope so I can turn a knob deep in her guts to adjust the current across a nano-scale tungsten emitter that may or may not actually work.

The chiller was clanking and emitting a bit of smoke. The thermometer read 75, but it was supposed to be holding at 65. Emergency abort, shut it all down.

It was coming from the other room, where the chiller lives.

It was at this point that I noticed the sound. And the smell.

Now for normal flash adjustment. Tear into the bowels of the main power supply. Remove one panel from the HV tank. Locate VR7. Poke your screwdriver into the live HV supply while crouching inside the high current supply. This is about a ten minute job. Thanks, JEOL.

Strong flash: not a problem. Turn a tiny potentiometer on the HT I/O board, on the right of the chassis. A quick adjust and the strong flash is verified within spec.

Lo and behold, both the normal and strong flash currents were quite low. It's possible that this emitter simply hasn't gotten enough current to be properly flashed. So let's adjust it up.

I wanted to verify that the flash current (2.4A normal, 2.8A strong) was, in fact, to spec. To do that I had to pull off the HV "top hat" (basically a glorified extension cord with six bolts holding it down) and hook up an ammeter.

After an extensive flashing regimen, the beam got worse, and eventually vanished altogether.

The Ecuadorean Authorities have no reason to detain free software developer Ola Bini: #eff #freeolabini

Tonight I'll tackle conditioning and alignment. Still a lot to do (and maybe go wrong) before I can take an image, but this is the most promising emitter yet.

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