Making of The Pill Bottle Radio
Michael Shaw, June
2018
Pill Bottle Radio
If you’re like me, you like to have a portable AM/FM radio
on hand just in case you want to catch your favorite shows or to hear the news.
Now this being hurricane season, it’s also great to have for emergencies too!
In this article I’ll explain how to make a good quality rechargeable portable
radio that fits inside a recycled pill bottle. It’s pretty easy and cost less
than $50 and takes only a few hours to make, if you don’t count the time it
takes to make the 3D printed cap.
This design was inspired after realizing I didn’t have a
good enclosure to mount the components of the radio I just built in. I had
purchased a SparkFun ESP8266 Thing WIFI Internet Board and interfaced it to the
SparkFun FM Tuner Evaluation Board and a Lithium Ion battery.
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| SparkFun ESP8266 Thing |
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| SparkFun FM Tuner Evaluation Board |
Since I’m older I now have to take maintenance drugs on a
daily basis. This means I have a few empty prescription bottles lying around. I
happened to take the components of the FM radio and slip them into an empty
pill bottle and realized it all fit! I just needed to figure out how to mount
it all in the pill bottle so I could plug in the head phones and the charger. I
thought about cutting slots and poking holes in the existing cap but this
wasn’t the best solution. What I needed to do was to make my own cap so it
would be strong and work reliably. At about this time I got my first 3D printer,
so I set out to make my own cap with the supports and mounting holes that I
needed.
I used a free 3D CAD program to come up with the following
drawing for a new pill bottle cap with the mounting for the boards built in:
I had to make a few iterations until I got the cap just
right, since it was trial and error to get the threads correct. By the way, the
pill bottle size is known as a 30 DRAM size bottle and is approximately 38mm in
diameter at the center.
Once the cap was finished it was just a matter of wiring up
the ESP8266 Thing to the FM Tuner Evaluation Board. I wired the boards together
using the wiring diagram below:
Now I was ready to program the ESP8266
Thing with some software. The software I created is basically a mash-up of the
SparkFun’s ESP8266 AP Web Server example sketch and the Si4703_breakout test
sketch. Note: to fit both the boards in the bottle you can’t use any headers to
connect the two boards together, except for the DTR/RST jumper. Instead I direct
wired both boards together as you can see in the picture below:
This is a problem, though, because
you won’t be able to connect the programmer. You can make a short wiring
harness by soldering wires to header pins and then tucking them out of the way
or you can use pogo pins (what I used) to temporarily connect the FTDI communications interface to the
ESP8266 Thing.
Once programmed you’re ready to try
it out. Plug in the battery to the Thing and turn it on. Connect to WIFI on
your phone and look for the WIFI network named “Radio Thing nnnn”, where nnnn
is the last digits of the Thing’s MAC address. Connect to the network and when
prompted, enter the password “Sparkfun”. Now open the browser on your phone and
enter the address 192.168.4.1/ and the screen similar to the following should
be displayed:
Now you can type in “up” or “down”
after the network address to change the volume or type the letters a,b,c to switch to a
pre-programmed station. These are my settings, but you can change them in the Thing’s
program to whatever you want.
I’m really happy with the performance
and the sound quality of the radio and not having to wire a bunch of switches
and knobs to get it working is icing on the cake. Plus I have a sturdy enclosure that was cheap
and easy to make, if you have a 3D printer. The files you need to make on just like it
will be listed here. Thanks and enjoy some easy listening!
