The call numbers that the library attaches to materials are stored in a different part of the data base from that accessed by all other search types. Because this table is called the "Marc Format for Holdings", or "mfhd", the vendor begins all field codes concerning call numbers with the letter M.
The standard call-number search performs well for Dewey Decimal or Library of Congress call numbers (e.g. for books) but not often for other materials, such as sound recordings, maps, and video tapes. A special field code is provided called "MOTH" (which stands for mfhd-other) in order to peruse areas of these indexes as though you were browsing among the items themselves on the shelves.
Although you must use the keyword-search section of Pilot to specify this code, it is actually a left-anchored search type. This means that it will find entries that either match the desired term exactly, or that begin with it-- rather than occurrences of the term anywhere in the text-- in the same manner as the title, author, and subject searches.
Finish the search term with a question mark in order to find a starting point at which to browse in the index. Omitting the question mark will produce a search that trys to retrieve a single call number given exactly. such Searches will probably fail.
The following example lists the compact discs that the West Chester University Music Library has classified as anthologies of choral music: MOTH C7