Fidelity Chess Challenger: Models, Manual and History of the Line

History of the Chess Challenger

Fidelity Electronics started in 1959 as a maker of hearing aids. Sidney and Myron Samole bought the company in March 1970, and the company began developing dedicated chess computers in 1976. Sidney Samole promoted the new machine at the Consumer Electronics Show in Chicago in January 1977, and the programmer Ron Nelson is credited as designer of the early Challengers. The Computer History Museum holds a Chess Challenger dated 1978 and names Samole and Nelson as its creators, in an entry that describes the Chess Challenger as one of the most successful chess boards.

The Fidelity Chess Challenger line carried the company for more than a decade. The Chess Challenger 7 is reported to have sold about 600,000 units, and that success is credited with the move of the firm from Chicago to Miami, Florida, in January 1981. Dan and Kathe Spracklen, known as the programmers of Sargon, joined Fidelity in 1979 according to the Spacious Mind collection, and the Chessprogramming wiki records that Fidelity machines won the first four World Microcomputer Chess Championships, from 1980 to 1984. By 1989 Sidney Samole had sold the company to Hegener & Glaser.

Fidelity Chess Challenger models

The list of Fidelity Chess Challenger models is long, and the sources do not always agree on the year, since a machine could be announced, sold and revised in different seasons. The chessprogramming.org list gives these entries:

Model	Year	Processor
Chess Challenger 1	1977	8080
Chess Challenger 3	1977	8080, 2 MHz
Chess Challenger 10	1978	Z80, 4 MHz
Chess Challenger 7	1979	Z80
Chess Challenger Voice	1979	Z80, 4 MHz
Champion Sensory Chess Challenger	1981	6502, 2 MHz
Elite Champion Sensory Chess Challenger	1982	6502, 4 MHz
Chess Challenger Micro	1991	HMCS40, 0.6 MHz

The first Fidelity Chess Challenger models were programmed by Ron Nelson. The sensory machines came from the Spracklens, and the Micro, a pocket unit, from David Levy and Mark Taylor. The spacious-mind.com collection pages add that the Challenger 10 came in a Version A in 1978 and a Version B in 1979, and that a Challenger 7 variant labelled BCC followed in 1980.

The original unit was a plain device. A collector’s account describes the first Chess Challenger as playing very weakly, accepting illegal moves and unable to take a move back, and Fidelity later offered a paid ROM upgrade to a three-level program.

The Challenger 10 and Challenger 7 in detail

In the Spacious Mind listing the Challenger 10 Version B is dated 1979, a year after the Version A, while the Chessprogramming list dates the Challenger 10 to 1978. The Version B used a Z80 at 4 MHz with 4 KB of ROM and 512 bytes of RAM, and a four-character LED display. It offered ten levels and an opening book of 69 half-moves, and it could set up and verify positions and change sides, but it had no takeback. According to its manual, level 1 averaged 3 seconds a move, level 5 about 2 minutes 20 seconds, level 7 was a 24-hour postal-chess setting and level 10 was tournament practice at 3 minutes. Level 6 was reserved for mate-in-two puzzles. The two software versions can be told apart by a short test: after 1. d4 d5 2. c4 c6, Version A plays 3. Nc3 and Version B plays 3. Nf3.

The Challenger 7 is dated 1979 by the Chessprogramming wiki, while the Spacious Mind page for the BCC model gives 1980. That machine used a 4 MHz Z80, 4 KB of ROM and 512 bytes of RAM, seven levels and an opening book of 100 positions. Its manual says the machine picks at random among moves it judges equally good so that games differ, signals a book reply with a single beep, and is designed to be left switched on for days or weeks.

The Champion Sensory Challenger was a different class of machine: a 6502 at 2 MHz, 16 KB of ROM, 4 KB of RAM, an 8 by 8 inch pressure-sensitive board, twelve fixed levels plus an infinite one, and a spoken vocabulary of about 50 words.

Finding and reading a Chess Challenger manual

A Fidelity Chess Challenger manual is easiest to find through collectors’ archives. Hein Veldhuis maintains a Dutch database at schaakcomputers.nl whose PDF section is sorted by maker, with Fidelity among them, and entries are prefixed by month and year. The spacious-mind.com Fidelity collection has a page per model with spec tables and, for some, quoted passages from the owner’s manual. This page does not host or copy any manual.

To read a Chess Challenger manual, first identify the model from the case and the model number, then match it to the manual of the same version. The Challenger 10 shows why: two software versions share a name but play differently. The Challenger 10 manual is quoted with a table of ten levels and their average time per move, and the Challenger 7 manual is quoted on random choice between equal moves, the single beep for a book reply and running the unit for days. Level tables like these are the most useful part for an owner, because they give average thinking time per move.

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