That's a Fluke 77 Series III, I think similar but with different specs.
e.g. the display resolutions are different
77 Series III
Digital: 3,200 counts, updates 2.5/sec
Analog: 31 segments, updates 25/sec
Response Time of Digital Display V ac < 2 s
V dc < 1 s
W < 1s to 320 kW, < 2s to 3.2 MW, < 10 s to 32 MW
79 Series III
Digital: 4000 counts, updates 4/sec
Analog: 63 segments, updates 40/sec
Frequency: 9,999 counts
Capacitance: 9,999 counts
V dc < 1 s
W <1 s to 40 kW, <2 s to 4 MW, <10 s to 40 MW
79 III calibration manual -
http://assets.fluke.com/manuals/7926____cieng0200.pdf
I did find a Fluke 79/26 Series III Multimeter Instruction Sheet but not the service manual. Downloaded and saved but have seem to lost the url.
IIRC a 77 series IV
Digital: 6000 counts, updates 4/sec
Bar Graph: 33 segments; updates 32/sec
Frequency: 10,000 counts
Capacitance: 1,000 counts