scope:

This specification covers the general requirements for quartz crystal units.

The PIN for crystal units meeting all the requirements of this specification are coded as shown and as specified (see 3.1):

Crystal units are identified by the two letter symbol "CR".

The number identifies a type of crystal unit which has certain electrical and physical characteristics covered as described in the specification sheet (see 3.1). The number comprises one or more digits and a letter (if applicable) indicates a modification of the basic type (e.g., 15B).

The basic application for which a crystal unit has been designed is indicated by the symbol "/U" denoting "general utility". Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use in improving this document should be addressed to: US Army Communications-Electronics Command, ATTN: AMSEL-LC-LEO-E-EP, Fort Monmouth, NJ 07703-5023 by using the Standardization Document Improvement Proposal (DD Form 1426) appearing at the end of this document or by letter.

The specified frequency expressed in hertz (Hz) is identified by eight characters, consisting of seven digits and a letter. The letter is used simultaneously as a decimal point and as a multiplier. For frequency values:

a. Greater than or equal to 1,000 Hz but less than 1 megahertz, the letter "K" is used to represent a decimal point.

b. Greater than or equal to 1 megahertz, the letter "M" is used to represent a decimal point.

All digits preceding and following the letter (K or M) of the group represent significant figures. The following are examples of using the eight characters in constructing the specified frequency:

Designation Frequency 1K000000 to 9K999999 1 to 9.999999 kilohertz, inclusive 10K00000 to 99K99999 10 to 99.99999 kilohertz, inclusive 100K0000 to 999K9999 100 to 999.9999 kilohertz, inclusive 1M000000 to 9M999999 1 to 9.999999 megahertz, inclusive 10M00000 to 99M99999 10 to 99.99999 megahertz, inclusive 100M0000 to 999M9999 100 to 999.9999 megahertz, inclusive

intended Use:

These crystal units are intended for use in military equipment systems for frequency control.