Zodiac the Astrology Computer by Coleco: History and Demonstration

The Zodiac Astrology computer was a consumer product created by Coleco in 1979 intended as a “personal astrology assistant”.


From the manual writer and noted Astrologist Sydney Omarr:

“Until the age of electronics, these detailed horoscopes and personalized interpretations were available only through the assistance of an astrologer, or as the result of hours of laborious personal calculations. But with ZODIAC — The Astrology Computer, you’ll be able to get the same kind of information in minutes — at home!”

Basically, this neat circular computer is able to tell you your astrological readings by entering your birth date, time, and location information. It even has different modes for daily horoscopes and advice-giving. The computer essentially spits out some numbers based on the birthdate information you give it. Then you write those numbers down and review what they mean in the manual.

A more detailed explanation of each mode from the manual:

“ZODIAC — The Astrology Computer operates in three different modes. In the Horoscope Mode, ZODIAC will give you a readout of the planetary positions at the time of your birth, and a list or corresponding potential personality traits. You’ll be able to chart horoscopes and develop interpretation for yourself, your family and your friends.

“In the Daily Preview Mode, ZODIAC will give you an update for any day — present of future!

“And in the Advice Mode, ZODIAC will supply you with advice based on astrological principles for your questions concerning all areas of your life.

“Using ZODIAC — The Astrology Computer in conjunction with this manual, you will soon be dealing into the mysteries of the zodiac, and discovering what celestial relations may concern you.”

About “Coleco” the maker of the Zodiac (from Wikipedia):

Coleco Industries, Inc. was an American company founded in 1932 by Maurice Greenberg as The Connecticut Leather Company. It became a highly successful toy company in the 1980s, known for its mass-produced version of Cabbage Patch Kids dolls and its video game consoles, the Coleco Telstar dedicated consoles and ColecoVision. While the company disappeared in 1988 as a result of bankruptcy, the Coleco brand was revived in 2005, and remains active to this day.

About the author of the manual’s introduction, Sydney Omarr:

From Wikipedia:

Sydney Omarr (August 5, 1926 – January 2, 2003) was an American astrologer and an astrology consultant to the rich and famous. His daily Sun Sign Horoscope column appeared in more than 200 newspapers and his annual forecast books for each sign of the zodiac sold over 50 million copies.

From the manual:

“Called by Time Magazine ‘astrology’s most skillful protagonist’, Sydney Omarr has attracted more attention and respect than any other astrologer in our lifetime. He has become one of the world’s leading authorities on astrology, and has won the attention, praise and respectof specialists in many fields, including countless authors and columnists, and leading personalities in business, government and the arts.”

Here’s a pdf of the original manus (in English and French): https://www.handheldmuseum.com/Manuals/Coleco-Zodiac.pdf


How to use the Zodiac:


The Zodiac must be used in conjunction with its manual. This is because after entering your birth information into the Zodiac, it will print numbers on the screen for which you must write down and look up in the manual to translate the interpretations from computer code to human language.

It is also recommended to print out this blank astrological canvas to write down your astrological information. The original product includes copies of these but they no longer exist in our copy. 


Instead, I’ll use a blank astrological chart from here to write down all the necessary info: http://www.internationalastrologers.com/blank_chart_JPG.JPG



Horoscope Mode:

This mode is used to make an astrological chart for anyone. However, they must have been born between 1900 and 1990. I guess there were more limits to hardware in the 70s?

For this guide, Adabot kindly volunteered for me to do his astrological chart with the Zodiac. So I must first gather the necessary codes from the manual based on the birth date, time, and location of Adabot.

Adabot was born (allegedly) on April 28, 1986.

First I’ll look that date up in the manual. On page 30 we see the closest date given to April 28th in 1986 is April 27th. According to the manual, “If the exact date is not listed, use the date just before the date of birth.” Thus I’ll write down the code next to 4/7: 4118 4P69 –


Next, I’ll look up the AREA CODE based on the place of birth page

Since Adabot was born in NYC, his AREA CODE is 20. I’ll write that down on my sheet

Now it’s time to enter the numbers into the Zodiac!

First, push the MODE switch of the Zodiac to the “H” position.

This will turn on the Zodiac and set it to Horoscope mode. You will see red leds circle around the zodiac and some music will play. Additionally, the screen will read “dA h” This is the Zodiac asking you to put in the date in the Horoscope mode.


Now enter the birth date code: 41184P69

The minus sign after the code will not be used here but will be later (-)

Press the enter button and you will now be prompted to enter the AREA CODE. I enter 20 for NYC’s area.

I’m now prompted to enter the time of birth: 6:00 am

Once I press enter, the Zodiac will start printing a series of numbers and symbols indicating the “list of planets according to their computed sign of the Zodiac location. The display will show each planet’s position according to the sign number.”

I will write these down.

Next, I must adjust the Mercury position as “Mercury is the fastest moving planet and its position may require adjustment” This is where the minus sign next to the birth code comes in. I will subtract the number that I was initially given (2) by 1 to get the adjusted position which is now 1 (Aries).

I’ll now fill in Adabot’s Astrology form with this information.

Next, I’ll press enter on the Zodiac to get Adabot’s interpretations and personality traits. Zodiac will print out a series of numbers now that I’ll write down. If the words “POS” or “NEG” appear before the numbers, I’ll record those as well.

Then I’ll refer to the manual for these numbers on the personality interpretations on pages 31-36. Then I’ll write down each corresponding personality interpretation.

The + and – before a number indicates a weaker or stronger interpretation of the potential personality trait.

Adabot is certainly a “practical – steady decision-maker”

And that’s it for Horoscope mode! It’s by far the most labor-intensive mode.

Daily Preview Mode:

“With the switch in the “P” position Zodiac gives you an “updated” horoscope for any day you wish, in the present or future”.

Given that the Zodiac was released in 1979, it only so this mode is generally useless to Adabot now. This is because the “future” ends in 1999 in this manual i.e there are no more date codes past 1999…

The way it works is you enter a date in the present or future into Zodiac along with a place and a time. Then Zodiac prints out a series of numbers that correspond to interpretations on pages 48 – 63.

Advice mode: 

“With the switch in the “A” position Zodiac becomes a friend and advisor. Zodiac gives you answers to questions pertaining to investments, trips, courtship, work, or any subject you wish to enter for any day you desire…. Zodiac gives advice based on astrological conditions which are computed from information entered by the person asking advice. Each person asking advice of the Zodiac must enter his own personal astrological information”

This mode requires you to write down a question as well as the date, place, time, sign number (of asker), and “house number” pertaining to the question.

The house number can be found on page 68. The house number corresponds to the topic of the question.

Once this info is entered into Zodiac, it will give you an answer to your question in one of the following ways:

“GO GO GO” (very strong yes)

”Do GO” (strong yes)

”YES” (average yes)

”GO SLO” (approach with caution — use discretion)

”nO” (average no)

”No GO” (very strong no)

And that’s all the modes! I hope you enjoyed delving into this esoteric piece of technology. Sydney Omarr wants to remind you:



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