From the serial number deciphering memo shown at the bottom of this post, I think your saw was built in 1980, Day 210 (Jul 28), 1375th unit built on assembly line 7.
Text below from a Homelite Technical service bulletin
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HOMELITE-JACOBSEN
TECHNICAL SERVICE BULLETIN NO. 185-008
SUBJECT: SERIAL NUMBERS
AFFECTS: ALL MODELS
The following information should answer most of your questions regarding serial numbers and how to read them.
EXAMPLE: Serial number: 4G1521238
"4" - This number specifies the assembly line the unit was built on. This could also be represented by a letter.
"G" - This letter specifies the year of final assembly. (See letter codes below). Before a letter was used to specify the year, a number was used. (See numeric code below).
"152" - The next 3 numbers specify the calendar day of the year (day 152).
"1238" - This was the 1,238th unit built that day.
"G152" - These 4 digits make up the LOT NUMBER.
LETTER CODE FOR YEARS:
C-1981 D-1982 E-1983 F-1984 G-1985 H-1986 I-1987 J-1988
K-1989 L-1990 M-1991 N-1992 O-1993 P-1994 Q-1995 R-1996
S-1997 T-1998 U-1999 V-2000 W-2001 X-2002 Y-2003 Z-2004
PREVIOUS NUMERIC CODE:
2-1972 3-1973 4-1974 5-1975 6-1976 7-1977 8-1978
9-1979 0-1980 1-1981
Prior to the 9-digit serial number now being used, an 8-digit number was used. The 8-digit number reads the same as the 9-digit number except the assembly line designation was not used.
Peery Gibson Service Manager Forestry Products
HOMELITE TEXTRON DATE: 3/85
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