Edward A Moore

US Patent:

40094510, Feb 22, 1977

Filed:

Jun 12, 1975

Appl. No.:

5/586227

Inventors:

Edward B. Moore - North Caldwell NJ
Donald P. Ryan - Pine Brook NJ

Assignee:

Edo-Aire, a Division of Edo Corporation - Fairfield NJ

International Classification:

H03B 536
H03J 102

US Classification:

331 64

Abstract:

To provide the required multiple channels for an aircraft communications system, a crystal controlled reference oscillator includes a tunable circuit for changing the base reference frequency provided by a crystal. The base reference frequency of the crystal controlled reference oscillator is pulled in frequency by changing the capacitance shunting the crystal. Two transistor switches change appropriate capacitors in series with the usual oscillator capacitor to obtain the capacitance values needed to pull the base reference frequency and thereby provide additional reference frequencies. The transistor switches are controlled by pilot actuated controls that operate a sliding display mark over a digital frequency indicator.