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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 "science ghetto" on the west end of the south wall at 2169.
* lives in the room that used to house the laser cutter
* is tended by Mike Kan and the rest of the [https://www.noisebridge.net/mailman/listinfo/sem SEM mailing list]
* is tended by Mike Kan, Alan Rockefeller, Chris and Jim and the rest of the [https://www.noisebridge.net/mailman/listinfo/sem SEM mailing list]
* camera mounting stage and bellows hood for slow-scan exposure. Proposed (2010-06-15), Completed by Mike, Miloh, and Chris (2010-11-06)


=== 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).
# If you vent air into the column without powering down the filament, you'll probably destroy the filament ($100).
# If you


=== Startup procedures ===
=== Startup procedures ===
# get the power cord from Mike.
# Get the power cord from Mike.
# (to be continued)
# See PDFs on vacuum start up and operators manual linked below.


=== Todo list ===
=== Todo list ===
# column liner needs to be replaced.  Larry may be able to provide a clean liner. (2010-06-15)
Short Term:
# (long term) build digital capture stage to replace CRT mechanism (2010-06-15)
# Isolate vibration from external sources; buses, people, etc. See Repair and Enhancement notes below. (2010-12-12)
# build sputter coater for specimen preparation (2010-06-15)
# Create/obtain specimen stage clamp or spring to prevent specimen vibration. (2010-12-12)
# Obtain some sputter coated specimens. (2010-12-12)
 
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)
# 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)
# 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)
# Diagnose and repair barrel distortion and occlusion at low magnification (2010-12-12)
# Sew dust cover (2010-12-12)
# Rubber grommet around edge of CRT potentiometer port needed
 
=== Repair and Enhancement Notes===
* Before repair, disable pumps and high voltage then put it into operation mode by placing a magnet on the operation relay.
* schematics framed behind SEM are to a similar, potentially slightly more modern model
* poorly designed wire harness may cause linear op amp and transistor on the J1 board of the power module to fail. 
* camera mounting stage and bellows hood for slow-scan exposure. Proposed (2010-06-15), Completed by Mike, Miloh, and Chris (2010-11-06)
* CRT V. scan, V bias, H. frequency potentiometers are located on the underside of the CRT module. 
* broken stigmator Y lock tab is in altoids tin in SEM kit box.
 
How to mitigate vibration:
# Measure and pinpoint vibration sources
# Dampen vibration from the rough pump-line by one of these methods: routing it through a concrete block and adding a hose extension,  sandbag the existing line, or utilize water as a mass.
# Hang the column from the ceiling with bungee cord and platform
# Potentially relocate the microscope to the server room to diminish dust and increase distance from Mission St.
# Create spring clamping specimen slug to keep the specimen from moving.
 
=== Specifications ===
* Made in Japan
* Delivered in September, 1975
* magnifies up to 20,000x
* outputs to a CRT
* non-digital, non-NTSC, non-PAL, analog output signal
 
=== Documentation ===
[[Media: Vacuum_System_Operating_Instructions.pdf]] - How to start the pump
 
[[Media: ISI_Mini-TV_SEM_Manual-Troubleshooting-Reference_Guide.pdf]] - How to use and fix the SEM
 
[[Media: Specimen_Stage_Service_Request.pdf]] - Why the rotating stage is broken
 
[[Media: Cards.pdf]] - Historic docs
 
[[Media: Other_Docs.pdf]] - Repair notes
 
[[Media: Packing_Lists.pdf]] - Original Packing Lists, the contents of the shipping crate
 
=== Schematics ===
 
Overall schematics for the TV MINI-SEM (Model: MRS-2-2 WN76-7-01). These schematics are for a model of SEM that is perhaps newer than than the SEM at Noisebridge. It is still an invaluable reference to the technician. Note: This schematic is a mosaic of 9 images stitched together with [http://hugin.sourceforge.net/ Hugin 2010.2.0]. Some minor alignment issues exist in the content of the schematic. I think alignment can be guessed/interpreted accurately.  Available in:
[[Media: TV_MINI-SEM_Schematics-Overall_MRS-2-2_WN76-7-01_Mosaic_v._1.0_Low-Res.jpg | LOW RES 1.5MB (4330 x 3109, posterized grayscale, JPEG)]] and
[[Media: TV_MINI-SEM_Schematics-Overall_MRS-2-2_WN76-7-01_Mosaic_v._1.0.jpg | HIGH RES 8MB (8680 x 6217, color, JPEG)]].
 
[[Media: Schematic_of_Photomultiplier.pdf‎]]
 
[[Media: Polaron_Pirani_Schematics-PE_Pir-SW_Issue_4_E5000.pdf]] - Polaron Pirani sputter coater schematics
 
[[Media: Polaron_Pirani_Gauge_Head_for_Sputter_Coater.pdf]]
 
=== Specimen Images ===
 
<gallery widths=200px heights=166px>
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_0652.jpg|Mechanical pencil graphite smudge on aluminum slug. 1000x magnification. This is post repair of X Stigmator. Imaged by the Noisebridge SEM. Mike Kan, Chris Murphy.
 
Image:IMG_0655.jpg| Tip of mechanical pencil graphite  on aluminum slug. 500x magnification. This is post repair of X Stigmator. Imaged by the Noisebridge SEM. Mike Kan, Chris Murphy.
 
Image:IMG_0654.jpg| Tip of mechanical pencil graphite on aluminum slug. 1000x magnification. This is post repair of X Stigmator. Imaged by the Noisebridge SEM. Mike Kan, Chris Murphy.
 
Image:IMG_0656.jpg| Tip of mechanical pencil graphite on aluminum slug. 5000x magnification. This is post repair of X Stigmator. Imaged by the Noisebridge SEM. Mike Kan, Chris Murphy.
 
Image:IMG_0657.jpg| Tip of mechanical pencil graphite on aluminum slug. 10,000x magnification. This is post repair of X Stigmator. Specimen was moving on the slug due to mechanical vibration. Imaged by the Noisebridge SEM. Mike Kan, Chris Murphy.
 
Image:IMG_0624.jpg|Semiconductor ball grid array at 20x magnification prior to repairing the X Stigmator. Mike Kan, Chris Murphy
 
Image:IMG_0649.jpg|Snapped metal region of a box cutter razor blade. Imaged on the Noisebridge SEM. About 5000x magnification. This is post repair of X Stigmator. Mike Kan, Chris Murphy
 
Image:IMG_0007.jpg|Head of a small 2mm allen type machine screw. Less than 1000x magnification. This is post repair of X Stigmator. Mike Kan, Chris Murphy
 
Image:Allen_close_up.jpg|Head of a small 2mm allen type machine screw. About 1000x magnification. This is post repair of X Stigmator. Mike Kan, Chris Murphy
 
Image:IMG_0026.jpg|Diatom imaged in fast scan mode (lower resolution than slow scan photo mode). Magnification unrecorded. Mike Kan, Chris Murphy. 12/12/10
 
</gallery>
 
[[Category:Pages with a Noisebridge Tiny URL]]

Revision as of 04:03, 7 August 2012

The Scanning Electron Microscope at Noisebridge.

  • "TV Mini-SEM (R)" by ISI (International Scientific Instruments)
  • lives in the room that used to house the laser cutter
  • is tended by Mike Kan, Alan Rockefeller, Chris and Jim and the rest of the SEM mailing list

Warnings

  1. 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.
  2. If you vent air into the column without powering down the filament, you'll probably destroy the filament ($100).

Startup procedures

  1. Get the power cord from Mike.
  2. See PDFs on vacuum start up and operators manual linked below.

Todo list

Short Term:

  1. Isolate vibration from external sources; buses, people, etc. See Repair and Enhancement notes below. (2010-12-12)
  2. Create/obtain specimen stage clamp or spring to prevent specimen vibration. (2010-12-12)
  3. Obtain some sputter coated specimens. (2010-12-12)

Long Term:

  1. 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)
  2. Build digital capture stage to replace CRT mechanism (2010-06-15)
  3. Replace 8.4" slow scan CRT with slow scan XGA LCD? (see above)
  4. Build sputter coater for specimen preparation (2010-06-15)
  5. Test repair of X Stigmator circuit. Replaced 741 op amp. (completed, work began 2010-11-20, tested 2010-12-10)
  6. Adjust vertical overscan of CRT (completed 2010-12-12, including hack sawing access port to overscan potentiometers in the CRT module)
  7. Fix 2x magnification toggle switch (2010-12-12)
  8. Diagnose and repair barrel distortion and occlusion at low magnification (2010-12-12)
  9. Sew dust cover (2010-12-12)
  10. Rubber grommet around edge of CRT potentiometer port needed

Repair and Enhancement Notes

  • Before repair, disable pumps and high voltage then put it into operation mode by placing a magnet on the operation relay.
  • schematics framed behind SEM are to a similar, potentially slightly more modern model
  • poorly designed wire harness may cause linear op amp and transistor on the J1 board of the power module to fail.
  • camera mounting stage and bellows hood for slow-scan exposure. Proposed (2010-06-15), Completed by Mike, Miloh, and Chris (2010-11-06)
  • CRT V. scan, V bias, H. frequency potentiometers are located on the underside of the CRT module.
  • broken stigmator Y lock tab is in altoids tin in SEM kit box.

How to mitigate vibration:

  1. Measure and pinpoint vibration sources
  2. Dampen vibration from the rough pump-line by one of these methods: routing it through a concrete block and adding a hose extension, sandbag the existing line, or utilize water as a mass.
  3. Hang the column from the ceiling with bungee cord and platform
  4. Potentially relocate the microscope to the server room to diminish dust and increase distance from Mission St.
  5. Create spring clamping specimen slug to keep the specimen from moving.

Specifications

  • Made in Japan
  • Delivered in September, 1975
  • magnifies up to 20,000x
  • outputs to a CRT
  • non-digital, non-NTSC, non-PAL, analog output signal

Documentation

Media: Vacuum_System_Operating_Instructions.pdf - How to start the pump

Media: ISI_Mini-TV_SEM_Manual-Troubleshooting-Reference_Guide.pdf - How to use and fix the SEM

Media: Specimen_Stage_Service_Request.pdf - Why the rotating stage is broken

Media: Cards.pdf - Historic docs

Media: Other_Docs.pdf - Repair notes

Media: Packing_Lists.pdf - Original Packing Lists, the contents of the shipping crate

Schematics

Overall schematics for the TV MINI-SEM (Model: MRS-2-2 WN76-7-01). These schematics are for a model of SEM that is perhaps newer than than the SEM at Noisebridge. It is still an invaluable reference to the technician. Note: This schematic is a mosaic of 9 images stitched together with Hugin 2010.2.0. Some minor alignment issues exist in the content of the schematic. I think alignment can be guessed/interpreted accurately. Available in: LOW RES 1.5MB (4330 x 3109, posterized grayscale, JPEG) and HIGH RES 8MB (8680 x 6217, color, JPEG).

Media: Schematic_of_Photomultiplier.pdf‎

Media: Polaron_Pirani_Schematics-PE_Pir-SW_Issue_4_E5000.pdf - Polaron Pirani sputter coater schematics

Media: Polaron_Pirani_Gauge_Head_for_Sputter_Coater.pdf

Specimen Images