Randy Shivak's Spectrohelioscope Specifications:

1. Diffraction Grating- Bausch & Lomb 64mm X 64mm, 600g/mm, blaze angle 54deg 6min.
2. Linear Dispersion- 1.5 angstroms per mm.
3. Grating Resolution- .05 angstroms.
4. Littrow Focal Length- 104 inches.
5. Slit Height-1 1/4 inches.
6. Entrance and exit slits adjustable in width, plus both rotate to compensate for spectral line tilt.
7. Mototized X & Y motions to position image and Z motion to focus image on entrance slit.
8. Spectrograph head detached from optics to insure no vibration to the optics.
9. Numerical readout for the littrow lens focusing.
10. Motorized occulting disk.
11. Anderson prisms for visual work.
12. Precision screw drive for oscillating slits, with safety clutch.
13. Grating micrometer direct reading to .0001 inch and further grating control to .0000025 inch.
14. Height 70 inches. Depth 20 3/4 inches. Width 28 inches. Weight 170 lbs.
15. 25 ft. Vacuum tower telescope to 30 inches Hg.
16. 12 inch Lens diameter F26.6 plano-convex BK-7.
17. Coelostat design 12-3/8" primary, 12- 3/8" secondary, better than 1/10 wave.
18. Computer- DEC LSI 11/23 controls coelostat and dome functions.