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Heathkit H-11A Digital LS-11 computer with 8 inch drives

Manufacturer Heath/Zenith
Model H-11A
Date Announced November, 1977
Date Canceled Unknown
Number Produced Thousands to Tens of thousands
Country of Origin USA
Price $1,200 in kit form
Current Value $50-$500
Processor LSI-11
Speed About 2.5 MHz
RAM 32K words
ROM Up to 8K
Storage Paper Tape, 8" floppy disks
Expansion 7 slots
Video N/A
I/O Serial, Parallel
OS Options HT-11, UCSD-P, others
Notes The Heathkit H-11 was an expensive alternative to the Heathkit H-8 Computer that was supposed to provide the power of a DEC PDP-11/03 on the desktop. Unfortunately, mainly due to memory constraints, it wasn't quite able to do this but it was still a very serviceable machine. It's cost did keep it from becoming too popular.
Related Items in Collection H27 8" disk subsystem, tons of manuals, software and more.
Related Items Wanted Additional software, manuals, and the Heathkit H-10 paper tape subsystem.

The H-11 in my collection hasn't yet been fully evaluated but it does run without smoking. Look for updates and here as time permits.

Inside the H-11 computer

The H-11 came with several of the standard DEC cards

Heathkit H-11 manual and schematics

The H-11 came pretty much fully documented. Here are the Assembly manual and schematics

H-11 documentation binders

Tons of other Heathkit reference manuals were included in these binders.

H-11 DEC books

As were the appropriate DEC books.

Heathkit H-11 software on 8 inch diskettes

The system came with lots of software on 8" disks.

Heathkit H-11 software on 8 inch diskettes

Still more software for this system.

The H-11 gear in my collection was kindly donated by Gary Appel.

(Submitted December 16, 2008 20:32:12 by John Pratchios)

There is a ton of software for pdp11 machines (LSI-11) running RT-11 O/S available from DECUS (now encompass under HP). The old FTP library had lots of software for free download. I have an old DEC Pro-350 in my attic and software I have not touched in over a decade. Best regards, John Pratchios

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