Fire Control Equipment: Range Keeper Mark VII

YEAR: 1931
ITEM: Manual/User's Guide
COMPANY: United States Navy Gun Factory
COUNTRY: USA
IN OUR COLLECTION: Yes

This is the "user's manual" for the Range Keeper Mark VII, one of the Navy's early computers. Officially, it is designated as "NAVORD - O.D. No. 2114" and is entitled, "FIRE CONTROL EQUIPMENT -- RANGE KEEPER, MARK VII AND MARK VII, MODS. 1 AND 2". The document was originally prepared by the Ford Instrument Company on March 12, 1931. This particular edition is dated January 10, 1933 and it looks like revisions were made July 7, 1934.

We were extraordinarily lucky to find this manual to go with our Mark VII computer. We have scanned parts of it for research purposes. See the PDF files below and selected pics in the Image Section. If you are interested in parts we have not scanned, contact us.

Related Items

Documents

Documents for this item have not yet been scanned or not yet posted. There are a lot of pages...contact us if you have an immediate need. (Although there are not a lot of "immediate needs" for a 70+ year old computer!)

Exceedingly Rare

Other than the one in our collection, we are aware of just one copy of this manual. It is located in the collection of the US National Archives and Records Administration in Washington, DC. We hope to visit the national archives soon.

Hopefully, a couple more will pop up in someone's attic or buried in a storage room at a Navy base.

For more information, click on the link(s) below.

US National Archives and Records Administration

If you know the location of any other of these items, please let us know by contacting us at Director@TheComputerChurch.com .

OUR DEFINITIONS OF RARITY

One of a Kind: Only known existing item.
Exceedingly Rare: Only 2 to 10 known to exist.
Very Rare: Only 11 to 25 are known to exist.
Rare: Only 26 to 50 are known to exist.
Difficult: Difficult to find.
Available:Can be commonly be purchased.
Unknown: We cannot make a determination.

(For comparison: Many people consider the Apple-1 computer to be rare. As of 2025 there are 92 confirmed and probable Apple-1 computers.)

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