All AVL Eagle models are the same base hardware with different options. The series was later rebadged under the "IIE" name. (~1982-1984)
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Eagle I (IIE-1) - Z80, 16K, 1 Single Sided floppy
Eagle II (IIE-2) - Z80, 64K, 2 Single Sided floppies.
Eagle III (IIE-3) - Z80, 2 Double Sided floppies
Eagle IV (IIE-4) - Z80, 2 Double Sided floppies, 7.5mb hard drive
Eagle V (IIE-5) - Z80, 2 Double Sided floppies, 15mb hard drive

The "1600" Series are MS-DOS CP/M-86 computers that are not IBM hardware compatible.
Includes 8 MHZ 8086, 720x352 graphics mode, Quad Density 5.25" drive with disks formatted to 780K, and a SASI hard disk controller. Runs a special port of MS-DOS 1.25. Hard disk is the "A" drive.
Keyboards are "similar" to IBM. Has 24 function keys. (Use a DIN plug. Are they interchangeable?)
Pressing the "F" key at boot will boot the floppy, and pressing "T" will run bios tests.
(No model 1610 mentioned? - logically that might be a single drive model)
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Eagle 1620 - 8086/128K, 2 Quad density floppy drives, 4 Expansion slots available, ~1983
Eagle 1630 - 8086/128K, 1 Quad density floppy drive, 10MB HD, 3 Expansion Slots available (Same as 1620 with hard drive), ~1983
Eagle 1640 - 8086/512K, 1 Quad density floppy drive, 32MB HD, 3 Expansion Slots available, ~1984

The Eagle PC series is an IBM PC hardware compatible. It was the second hardware clone, following Columbia Data Products. Eagle copied some of IBMs BIOS code and IBM sued.
Infringing PCs stopped shipping on March 7 1984: https://books.google.com/books?id=hy...lus%22&f=false
Four ISA expansion slots, DSDD Floppy drives, On board serial and parallel.
A 24-function key keyboard available for the Eagle PC as an option.
All expandable to 640K (What is the "Plus" for?)
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Eagle PC-1 - 8088, 128K, 1 Double Sided floppy, one available expansion slot, ~1983
Eagle PC-2 - 8088, 128K, 2 Double Sided floppies, one available expansion slot
Eagle PC-XL - 8088, 128K, 1 Double Sided floppy, 10mb hard drive, one available expansion slot

Eagle PC-1 Plus - 8088, 128K, 1 Double Sided floppy, one available expansion slot (XL system without hard drive), ~Late 1983, 1984?
Eagle PC-2 Plus - 8088, 128K, 2 Double Sided floppies, one available expansion slot, (XL system without hard drive), ~Late 1983, 1984? (Sometimes written "Eagle PC Plus II")
Eagle PC Plus XL - 8088, 128K, 1 Double Sided floppy, 10MB hard drive. ~Late 1983, 1984

Eagle PC Turbo XT - 8mhz 8086, 256K, 10MB hard disk ~1984 (Actually Turbo XL?) ~1984

Spirit Series are luggable, with built-in 9-in CRT, like Compaq and Columbia Data Product VP1600
The Eagle Spirit is IBM PC hardware compatible.
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Eagle Spirit - 8088, 128K, 2 Double Sided floppy drives ~1983
Eagle Spirit-2 - 8088, 256K, 2 Double Sided floppy drives
Eagle Spirit XL - 8088, 128KB RAM, Max 640K, 1 Double Sided floppy drive, 10mb hard drive ~1983

Software packages
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EagleWriter - (rebadged Lexisoft Spellbinder)
EagleCalc - from Lattice