Hyperlocal radio in 1980s Tokyo

20.20, Friday 27 Oct 2023

In the early 1980s in Japan, a movement called mini-FM blossomed: a thousand tiny radio stations broadcast over just half a mile each.

One of the first stations was Radio Home Run, broadcast by Tetsuo Kogawa and his students from 1983–1996 in the Shimokitazawa neighbourhood of Tokyo:

This station took advantage of a loophole in Japanese broadcasting legislation, which stipulated that devices under a legally-defined power threshold — usually requiring less than one watt of power — could transmit on the air without a license. Using a legal very low-powered FM transmitter, members of Radio Home Run transmitted a signal able to reach listeners within about 500 meters of the station’s antenna. However, Tokyo’s high population density meant that this relatively weak transmitter still had massive possibilities, since its comparatively small coverage area still contained about “20,000 residents, all potential listeners”.

It was Kogawa’s realisation that low power radio was legal. They had intended to run a pirate FM station (Tokyo had only two official stations) but he discovered the exception in the regulations and started investigating cheap, sometimes hand-made transmitters.

Kogowa wrote books and pamphlets; journalists picked up the story whenever a new station opened.

He tells the story of mini-FM in Toward Polymorphous Radio:

Even major advertising agencies tried to open mini-FM stations. The exact number is unknown, but it can be estimated from the number of small transmitters sold that, in a year, over one thousand stations appeared in Japan. People on college campuses, in housing complexes, coffee shops and bars, stalls at street fairs and even local offices started mini-FM stations. More than ten companies, including Mitsubishi, Panasonic, Hitachi and Sony, sold a transmitter labelled “For mini-FM use”.

The intention was to change broadcast: The area that a one-watt transmitter covers is within walking or bicycling distance.

And so that early station Radio Home Run became a collective experience:

Radio Home Run transformed listeners into producers by inviting people tuning in to physically travel to the station’s nearby studio.

Corollary: it also revealed how strange typical everyday experiences of radio - through listening alone - actually are.

I’m skipping over so much!

How Tetsuo Kogawa’s concept of “polymorphous” media anticipated social media.

How physical movement would put the listener in “kinetic interaction” with the electromagnetic field from the transmitter, moving in and out of coverage.

btw here’s a great history of mini-FM with its whole context, appended to the shopping page for a hat? The hat is sold out.


Mini-FM left a legacy. Check this out.

From a review of the Sony Ericsson W980 Walkman – in 2008.

Finally we come to one of the most exotic and intriguing features of Sony Ericsson W980 - the FM transmitter allowing you to broadcast your favorite tracks. Those can then be picked up by any device with an FM radio receiver in the vicinity.

By this point the iPhone had been out for a year! The iPod was released in 2001.

Imagine if the iPod had shipped with a built-in FM transmitter and receiver! Each iPod owner a walking, combined broadcaster and listener.

Except that it wouldn’t have worked.

What we have a word for now is discovery. The vital feature of mini-FM was the potential audience re-tuning between known stations by running up and down the dial, volume up, stumbling across unheard-of stations.

The vital feature for a two-way iPod would have had to be something similar: a menu option labelled Nearby next to the albums and the artists.

Yet I can’t let go of that alternate history.

In our parallel universe, we’d all be users of Scott Jenson’s invention of the Physical Web. It was built into Android.

The Physical Web enables you to discover web pages associated with everyday objects and locations. …

When you are near a bluetooth beacon (and have bluetooth enabled), you will receive a notification for the Physical Web.

Like QR codes only I could carry a beacon in my pocket, get on a train, and the website would show up on the phone of all the passengers.

Again it’s all down to how you encounter the URL. As a push notification it’s a spam vector. As a “nearby” tab, more interesting? Possibly. It’s a tough one.

And related to this:

An iPhone app I am intrigued by is WorldWideWeb by IconFactory.

You open a folder on your phone with the app… and it becomes a website accessible for anyone else on the same wifi network.

Now, what is a shame is that Apple used to list local websites in Safari bookmarks (the technology is called Bonjour). This feature was removed back in 2017.

So we’ve got a discovery problem again.

Besides, the scale doesn’t match up. The lesson of mini-FM is that you need a potential audience of 20,000 producer/listeners, not only the people you can already see.

As someone who made fanzines at school (80 issues sold!!) - that being my route into the web - I do wonder about the mini-FM equiv for, well, not so much new media anymore as early-middle-aged media.

But modern broadcast doesn’t afford the fuzzy perimeters of 1980s FM radio.

I’m never going to be bored-browsing Netflix and get a faint glimmer of someone’s home-broadcast TV show wedged between menu items, there to view if I can tune in exactly right. My iPhone might be the means of production, in the right hands, but I’ll never own the means of distribution.

And that’s not a shame, not really, time moves on, our era has its own other freedoms. But still.

If you enjoyed this post, please consider sharing it by email or on social media. Here’s the link. Thanks, —Matt.