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Kosmos 1 Biorhythm Calculator


According to believers in biorhythms, a person's life is affected by rhythmic biological cycles which affect one's ability in various domains, such as mental, physical, and emotional activity. These cycles begin at birth and oscillate in a steady sine wave fashion throughout life; thus, by modeling them mathematically, a person's level of ability in each of these domains can be predicted from day to day.

Most biorhythm models use three cycles: a 23-day "physical" cycle, a 28-day "emotional" cycle, and a 33-day "intellectual" cycle. Although the 28-day cycle is the same length as the average woman's menstrual cycle and was originally described as a "female" cycle (see below), the two are not necessarily in any particular synchronization. Each of these cycles varies between high and low extremes sinusoidally, with days where the cycle crosses the zero line described as "critical days" of greater risk or uncertainty.

In addition to the three popular cycles, various other cycles have been proposed, based on linear combination of the three, or on longer or shorter rhythms.

Charting biorhythms for personal use was popular in the United States during the 1970s; many places (especially video arcades and amusement areas) had a biorhythm machine that provided charts upon entry of date of birth. Biorhythm programs were a common application on personal computers; and in the late 1970s there were also handheld biorhythm calculators on the market, the Kosmos 1 

Size (approx):70mm x 140mm x 27mm (w,h,d)

Weight 116g excluding batteries
Power: 4.5V DC, 3 x AA size batteries.  It accepts an adapter (DC 4.5V, 0.36W) through a socket on the top side in the middle.  The on/off switch is on the left hand side in line with the biorhythm chart.  Battery lifetime is quoted as 10 hours for dry batteries.
Case: Slightly curved upwards case made from two-piece black matt plastic construction.  The top area is dominated by a large aluminium panel printed in four colours with the brand and model number but more importantly the biorhythm look up table.  The green display filter is flat, slightly proud and gives a good clean display.  A set of six red and orange discrete LEDs are housed within the printed table.  The recessed keyboard has its own white plastic escutcheon. The keys are long travel and squishy but work well.  The whole thing looks like a Texas clone but feel heavier and better quality. The rear has a large metallic sticker with a handy Biorhythm PSI chart.
Display: 8 digit green VFD with a ninth digit for negative and error indication
Features: 4 function calculator with biorhythm functions.
Age: 1977
Manufacturer: Kosmos International Ltd., made in Japan
Further information can be found at http://www.vintage-technology.info/pages/calculators/k/kosmos1.htm

This 1977 Kosmos 1 Biorythym calculator was the property of Film Editor Peter Boita.

Peter Boita worked as a professional Film Editor from the late 1940's until the late 1980's working on such diverse films as:

Carry On Segeant
Swiss Family Robinson
The Far Pavillions

This advanced Biorythym calculator, soft case and instructions were his personal property and was purchased in the late 1970's and was very kindly donated by his son Peter Boita Jnr.


Manufacturer: Kosmos
Date: March 1977

This exhibit has a reference ID of CH24545. Please quote this reference ID in any communication with the Centre for Computing History.


Kosmos 1 Biorhythm Calculator

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