Getting Started with Digital Simple Radio

The Backstory#

I’ve always been interested in wireless communications. Back in elementary school, I tried a capsule toy machine that supposedly gave out toy walkie-talkies (a mysteriously smelly slime popped out instead, which I deeply regretted). In middle school, I remember watching the stage crew coordinate with two-way radios during a school performance and thinking, man, that’s so cool.

Electromagnetic waves have this vibe of being deeply intertwined with the occult. And I love the occult. The fact that I love the events in the first half of Volume 6 of The Demon Girl Next Door might actually trace back to this.

And so, I decided to finally buy a radio.

Types of Radios#

It turns out there are quite a few varieties when it comes to radio. For an ordinary person picking it up as a hobby, the following four seem to be the main contenders:

• Amateur radio
• Citizens band radio
• Digital Simple Radio
• Specified Low Power Radio

What I Ended Up Choosing#

I figured Digital Simple Radio would be the best fit.

Amateur radio seemed like a hassle in various ways, so that was ruled out.

If I was going to do radio, I wanted to experiment with different antennas, so Specified Low Power Radio—where swapping antennas is legally prohibited—was also out.

That left Digital Simple Radio, which seemed capable of reaching far without needing any help from things like the ionosphere.

Buying the Radio#

That said, Digital Simple Radio units are pretty pricey. If you try to buy one brand-new, spending over 20,000 yen is inevitable. Going for the latest models pushes past 30,000 yen.

While studying up on radios, I decided to scour Yahoo! Auctions and Mercari.

After keeping watch for about two weeks, I managed to snag a Kenwood TPZ-D503 for around 10,000 yen.

• Capable of 5 W output
• Just the right amount of ruggedness
• Kenwood radios supposedly have a reputation for good audio quality

Those were the main reasons.

Giving It a Listen#

It was technically sold as “junk” (as-is / for parts), so with my heart pounding, I powered it on. However, not a single channel received any signal. Was it actually broken junk after all…?

Topographically, my place sits in something of a valley, which might be why almost no radio waves make it in.

So I decided to head somewhere with a lot of people. Near Tokyo Station, on the 6th-floor rooftop garden of the KITTE building, I turned it on—and heard what sounded like on-the-job business chatter coming in across multiple channels. While waiting on the dedicated calling channel (Channel 15), a CQ came in from someone operating from the observation deck of the Sunshine 60 building in Ikebukuro.

At least the receiving function didn’t appear to be broken. I also started picking up all sorts of fascinating business radio transmissions. At one point, I even overheard comms from what sounded like a movie shoot.

This is ridiculously fun.

Registering the Radio#

You cannot transmit until your radio’s registration clears. I promptly set out to submit my paperwork to the Ministry of Internal Affairs and Communications.

There are two types of applications, and you can choose whichever suits you best:

• Individual Registration (kobetsu toroku)
  • Think of the registration as being tied to the radio itself.
  • You register each radio one by one. The registration certificate typically arrives within about 15 days.
  • Once registration is complete, you can start operating that radio.
• Blanket Registration (hokatsu toroku)
  • Think of the registration as being tied to the individual.
  • First, you apply for blanket registration, and after that is completed, you submit a notification of station establishment for the radio. The registration certificate typically arrives within about 15 days.
  • Once the blanket registration clears, you can freely operate radios from then on. However, you must submit a notification of establishment within two weeks of starting operation.
  • The fee is slightly higher than for individual registration.

I opted for blanket registration this time. That’s because when buying a second radio or more:

• The blanket registration fee works out cheaper than paying the individual registration fee for two radios
• As long as blanket registration is in place, you can start using any newly acquired radio the very same day

In my case, my paperwork went to the Kanto Bureau of Telecommunications.

I mailed it on a Friday, and exactly two weeks later on a Friday, the registration certificate arrived (including one national holiday in between).

I’d been on pins and needles wondering when it would come, so I was glad it safely arrived within the 15-day window.

This is getting long, so I’ll save the story of actually making contacts for another post.