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* "TV Mini-SEM (R)" by ISI (International Scientific Instruments)
* "TV Mini-SEM (R)" by ISI (International Scientific Instruments)
* lives in the room that used to house the laser cutter
* lives in the "science ghetto" on the west end of the south wall at 2169.
* is tended by Alan Rockefeller, Jeff Miller, Chris Murphy and Jim and the rest of the [https://www.noisebridge.net/mailman/listinfo/sem SEM mailing list]
* is tended by Mike Kan and the rest of the [https://www.noisebridge.net/mailman/listinfo/sem SEM mailing list]


=== Warnings ===
=== Warnings ===
# If you release the vacuum without venting the pump hose, pump oil will flood the chamber and contaminate the entire mechanism, requiring 10 hours of cleanup.
# If you release the vacuum without venting the pump hose, pump oil will flood the chamber and contaminate the entire mechanism, requiring 10 hours of cleanup.
# If you vent air into the column without powering down the filament, you'll probably destroy the filament ($100). The filament has a design lifetime of about 25 hours, depending on the current put through it. Adjust the specimen stage and other controls at low current, reserve higher currents for final photos.
# If you vent air into the column without powering down the filament, you'll probably destroy the filament ($100).
# Mike Kan has warned that if anyone asks him anything about the SEM, he's going to move it to another hackerspace. Jeff Miller has a MinI-SEM of his own, and knows its ins and outs pretty well.


=== Startup procedures ===
=== Startup procedures ===
# If the power cord is not already present, ask around or post to the list a few days prior to using the 'scope.
# Get the power cord from Mike.
# See PDFs on vacuum start up and operators manual linked below.
# See PDFs on vacuum start up and operators manual linked below.


=== Todo list ===
=== Todo list ===
Short Term:
Short Term:
# Isolate vibration from external sources; buses, people, etc. Mostly finished. (2013-6-20)
# Isolate vibration from external sources; buses, people, etc. See Repair and Enhancement notes below. (2010-12-12)
# Figure out what to do about the person(s) now "occupying" the clean room which houses the SEM. (2013-6-20)
# Design/build/find a sputter coater so the SEM can be used as a useful tool as well as a curiosity.
# Create/obtain specimen stage clamp or spring to prevent specimen vibration. (2010-12-12)
# Create/obtain specimen stage clamp or spring to prevent specimen vibration. (2010-12-12)
# Obtain some sputter coated specimens. (2010-12-12)
# Obtain some sputter coated specimens. (2010-12-12)
Medium Term:
# Build a forepump line vibration isolator. (2013-6-20)
# Relocate or otherwise isolate the forepump. (2013-6-20)
# Replace most of the rubber tubing with metal tubing to reduce outgassing and pump-down times. (2013-6-20)


Long Term:
Long Term:
# Column liner needs to be replaced.  Larry may be able to provide a clean liner. (2010-06-15) (update: Larry has taken column liner to his lab for cleaning)(update: column liner is now clean) (2013-6-20)
# Column liner needs to be replaced.  Larry may be able to provide a clean liner. (2010-06-15) (update: Larry has taken column liner to his lab for cleaning)
# Integrate the digital capture and control unit Jeff built for his own Mini-SEM into the unit. (2013-6-20)
# Build digital capture stage to replace CRT mechanism (2010-06-15)
# Replace 8.4" slow scan CRT with slow scan XGA LCD? (see above)
# Build sputter coater for specimen preparation (2010-06-15)
# Test repair of X Stigmator circuit. Replaced 741 op amp. (completed, work began 2010-11-20, tested 2010-12-10)
# Test repair of X Stigmator circuit. Replaced 741 op amp. (completed, work began 2010-11-20, tested 2010-12-10)
# Adjust vertical overscan of CRT (completed 2010-12-12, including hack sawing access port to overscan potentiometers in the CRT module)
# Adjust vertical overscan of CRT (completed 2010-12-12, including hack sawing access port to overscan potentiometers in the CRT module)
# Fix 2x magnification toggle switch (2010-12-12)
# Fix 2x magnification toggle switch (2010-12-12)
# Diagnose and repair barrel distortion and occlusion at low magnification (2010-12-12)
# Diagnose and repair barrel distortion and occlusion at low magnification (2010-12-12)
# Sew dust cover (2010-12-12). Sew/heat seam new plastic dust cover, evidently the previous dust cover was destroyed. (2013-6-20)
# Sew dust cover (2010-12-12)
# Rubber grommet around edge of CRT potentiometer port needed.
# Rubber grommet around edge of CRT potentiometer port needed
# Replace forepump with a (hopefully larger) pump that has a ballast port.
# Buy/find some real vacuum valves, turn simple spool pieces to serve as adapters, and electro-pneumatically interlock the valves so that valve sequencing is fool-proof.
# Evaluate air-cooled diffusion pump as source of vibration and contamination. Consider Santovac fluid and/or water-cooled pump and/or thermoelectric cold cap.
# Consider replacing filament with LaB6 cathode for brighter, sharper images and lower long-term per hour operating costs.


=== Repair and Enhancement Notes===
=== Repair and Enhancement Notes===
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=== Specimen Images ===
=== Specimen Images ===


<gallery widths=200px heights=166px>
<gallery widths=200px heights=166px perrow=6>
Image:IMG_0004.jpg|Image of mechanical pencil graphite smudge on an aluminum slug at approximately 20x magnification. The specimen is about 1 mm across. This is prior to repairing the X Stigmator. Magnification was limited. Imaged by Chris Murphy and Mike Kan.
Image:IMG_0004.jpg|Image of mechanical pencil graphite smudge on an aluminum slug at approximately 20x magnification. The specimen is about 1 mm across. This is prior to repairing the X Stigmator. Magnification was limited. Imaged by Chris Murphy and Mike Kan.


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</gallery>
</gallery>
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