JAN-

"JAN -" is no part of a tube name. It stands for "Joint Army Navy", a Tube Standardization Program of the US Military.
The actual tube name (designation) begins at least behind the hyphen.
Example: JAN -6789 = type 6789.

In some case a second string of characters follows, giving a reference to the tube maker. The actual tube name then begins behind the last hyphen.
JAN-CAA/CAGD- = Machlett
JAN-CAHG- = Chatham Electronics
JAN-CBOP- = Heintz & Kaufman
JAN-CBSC- = Burroughs
JAN-CBYS- = Central Electronic Mfrs.
JAN-CBZC- = Penta Labs.
JAN-CCSB- = Marshall Electronics Company
JAN-CCUQ- = Beam Tube Co.
JAN-CDR- = General Electronics
JAN-CDZ- = Electronic Enterprises
JAN-CEA- = Bendix
JAN-CEL- = Electrons Inc.
JAN-CEP- = Amperex
JAN-CFT- = Federal (ITT)
JAN-CGE/CG- = GE ( General Electric)
JAN-CHS- = Sylvania
JAN-CHY- = Hytron
JAN-CIM- = Eimac
JAN-CIZ- = Industrial and Commercial Electronics, Belmont, CA
JAN-CKR- = Ken Rad
JAN-CNU- = National Union
JAN-CNY- = North American Philips, Norelco
JAN-COZ- = Sonotone
JAN-CQN- = Slater
JAN-CRC- = RCA
JAN-CRP- = Raytheon
JAN-CS- = Sperry
JAN-CTL- = Tung-Sol
JAN-CUE- = United Electronics
JAN-CW- = Western Electric
JAN-CWL- = Westinghouse

Example: JAN-CKR-6789 = Type 6789, made by Ken Rad.