Author: Doug Carman

Business Telephones

Business communication has relied on multi-line and private exchange systems since the early days of the telephone industry.  Today’s IP based business telephones and software based telephone clients may seem like distant relatives of yesterday’s analog and digital phones.  However,

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Visiting Bletchley Park

Visiting Bletchley Park and The National Museum of Computing in Milton Keynes is well worth the trip.  The story of the code breaking effort during World War II is a fascinating tale of people and technology that was kept hidden

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RCA Radiola 30A

I like old technology in general, that extends to true antiques like this RCA Radiola Model 30A.  This radio turned up at a local Habitat for Humanity resale store.  I saw it shortly after it arrived and became interested enough

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The model AN/FSQ-7 and AN/FSQ-8 computers, commonly known as the SAGE computers, were central components of the first computerized air defense system in the United States. SAGE stood for “Semi Automatic Ground Environment” and was based on the concepts of

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DEC MicroVAX 3100-90

The DEC MicroVAX 3100 was a successful series of small VAX systems that DEC produced from the late 1980’s to the late 1990’s.  It was the size of a PC-AT style desktop, used small SCSI hard drives, and made an

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DEC Professional 350

The DEC Professional series of “personal” computers were desktop systems based on the PDP-11 line of minicomputers. The Pro 350 was based on the F11 processor from the PDP-11/23. It ran an unfortunately named operating system called P/OS, or rather

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sun 3/470

The Sun model 3/470 was the last and most powerful of the sun3 architecture systems based on the Motorola 68020/68030 family of processors. The system was comprised of a 12 slot VMEbus chassis with the Sun “3400” CPU board, up

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This PDP-11/70 was purchased in 1979 by Stromberg-Carlson for use in the development of software for the DCO digital central office telephone switching system. This system remained in continuous service until July, 2000, when it was replaced by a smaller

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Progress on the site

As I’m going through the process of getting this new Web site running, I’m reminded that I first started down the road with WordPress three years ago.  It’s certainly no fault of WordPress that it’s taken this long.  It’s a

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