|Motor:||d.c. servo with 25:1 reduction|
|Motor Encoder:||Scale: 1183.033 for FW1|
|Scale: 1182.261 for FW2|
|Rotation:||Positive is left as viewed through access port.|
|Overall Encoder:||1000 lines per rev. giving 1 arcminute|
|Limits:||none (although SCH 4028-1:3 shows limits)|
|FW1 Drive Amplifier:||Amp 9|
|FW2 Drive Amplifer:||Amp 10|
|Homing:||one per wheel connected to the HomeFlag|
|Positions per wheel:||9 (1,2,3,4,5,6,7,8,9)|
|Max Speed:||10 degrees per second 5 deg/sec/sec acc.|
|Filter Size:||4.5 inch|
Note: The schematic show "detents", these notches are closed when the filter is in position. They are connected to the +LIM.
There is a large set of filters available at the RCT. Each is a round filter close to 4.5 inches in diameter with widths ranging between 2 and 10mm. There is a set of broadband filters approximating the Johnson set and its extensions. Most of these are of the "colored glass" type. The broadband I filter, however, is an interference device. There is a larger set of narrowband interference filters centered on various nebular emission lines and off-line regions that will contain continuum emission.
The filters fit into large wheels located in the combined filter/guide camera box on the back of the telescope. Each wheel has 9 openings, with one slot (no. 9) left open on each filter wheel. This way, one filter is positioned in the beam along with an open slot on the other wheel. The filter slots are printed on the wheels with each number (1-9) stamped on the edge of the wheel directly opposite from the slot. The filter wheels rotate in both directions, either through a gentle push by hand or when commanded by the observatory software. The filters lock into position where a detent grabs onto notches on the side of the wheels.
The broadband filters, which are used extensively, are all located in filter wheel 1. Many of the narrowband filters are put in filter wheel 2, which is the wheel most easily removed from the telescope. A third filter wheel is available for storing a separate set of filters off the telescope. This wheel can be swapped with wheel 2.
Below are the current filter assignments to wheels 1 and 2. Some filters are kept in storage along with empty wooden filter boxes for the filters on the telescope. These filter boxes are kept in storage cabinets in the dome or control room.
|Filter Name||Header Value||Andover Part #||Central Wavelength (Å)||Width (Å)||Trans. plot|
|V||v||ANDV8667||V.gif / Valt.gif|
|green continuum #1||?||ANDV8164||4807||47||gr_cont1.gif|
|green continuum #2||5300a/green _continuum _#2||ANDV8167||5312||90||gr_cont2.gif|
|red continuum||6450a/red _continuum||ANDV8169||6458||80||rd_cont.gif|
|H (narrow)||6563a/halpha _1nm||ANDV8281||6565||9||Halpha_narrow.gif|