Sunday, October 17, 2021

Nintendo Love Tester ad sign (ca 1969)

In today's post we will take a look at a very special item in my collection: a sign used to promote the Nintendo Love Tester (ラブテスター) from 1969.

I do not know if this was an official item produced by Nintendo, but given the build quality and the unique feature it has (more on that below), I am assuming it is. It must be very rare, as this is the only one I have ever seen. If there were more, and there probably were, they probably have disappeared in the sands of time by now.

The Love Tester was a novelty item conceived by Gunpei Yokoi for Nintendo. It used simple electronics to provide a 'love score' to a couple holding hands.

The Love Tester was a considerabel success, helped by marketing material like the flyer above and this particular sign, that was likely placed in a shop or departement store to attract sales.

The sign measures around 35 centimeters wide, 40 centimeters high and 12 centimeters deep. It is lighted from inside, using a 110 volt fluorescent light.

At the top it gives the product name in both English and Japanese.

At the bottom it says "Let's measure the love between us two with electronics!", with that last word shown in large katakana script (エレクトロニクス) to emphasize that this is a modern, sophisticated item.

The Nintendo company name is add to the base.

The sign itself also has nice trick up its sleeve. The image is not static: the hearts, letters and faces of the couple continuously change intensity and colour.

The skin colours of the man and women alternate turning red, no doubt meaning they are blushing as a result of the Love Tester score.

If we accept that the 'natural' colour of the pair is blue and green, the red blushing is very convincing.

This effect is created in an original way, with a simple mechanism.

To understand how this works, we take a look at the back of the plastic sheet that holds the illustration.

Pieces of polarizing plastic are mounted strategically behind the various shapes. Behind the large characters spelling 'Electronics' they are placed in small strips, each with it's own polarizing direction.

Inside the sign, a circular piece of plastic is attached to an electric motor. It sits between the light and the sign image.

This piece of plastic is also polarizing (circular polarizing, to be precise). As it turns it creates the changing light effects, interacting with the polarizing pieces in the front.

That's all there is to it. Clever and simple, with only a single moving part. A piece of engineering that could well be conceived by the Nintendo R&D team of the time.

For more information about the Love Tester, check out this previous post.


  1. Any way we can see this in action, very interested in the effect this is meant to produce and cant seem to find too much info on this device online.

  2. Would it be posible you you to take a video of this sign in action, very interested in the effect your talking about.