LED Prop Phones

A total of 124 LED phones were created to enhance the high school marching band show. These props were made from acrylic and had a custom made battery pack and LED strip insert. Hours were spent researching available components to fall below the $300 allotted budget, and with some fellow band members the props built and delivered on time. They were successful enough to get multiple offers from other bands to buy the props when we were done with them.

How it Started

The marching band show theme was all about technology, and the band director had expressed a desire to get phones much like what is seen here. Yet unfortunately due to cost he would have to buy cheaper, "toy iPhone" props instead. Seizing the opportunity, I suggested that I (and a few other students) design and build the phones ourselves. Our wish was granted on the condition that it be done within three weeks, I provide a working prototype or proof of concept, and the project be cheaper than the non-glowing options. The budget was set at $300.

Design and Construction

LED Strip lights are run off a 12V power supply, meaning we needed to use an A23 battery.  AliExpress carried on/off switches linked with battery holders for significantly less than anywhere else. White LED light strips came from Amazon and the large acrylic sheets (to be cut down) came from an acrylic supplier.  After cutting out 124 acrylic blocks, the edges, faces, and corners were all sanded down to allow  the light to diffuse and produce the glowing effect.  A big slot was cut, and everything put together.

The electronic inserts turned into a huge pain to assemble. Any wires needed to be as short as possible, so we had someone cutting wires and stripping them incredibly short. Naturally, soldering that became a pain, and quality dropped. The first few worked great, and then as we continued to assemble the remaining 100+ inserts we started just throwing them together. To be honest, the last ones weren't even soldered at all, just twisted together and hit with some hot glue. The deadline was the next day and needed to be met.

This was absolutely no excuse for poor quality, but is rather an accurate reflection of what actually happened.

These things can really put off a lot of light! I took a spare insert I had camping and used the same light diffusion technique to turn my water bottle into a lantern. It worked really well.

Fixing Things

Naturally, since the phones were held together with mostly hot glue, some of them broke. Wires would become unconnected, inserts would occasionally fall off. We had made plenty of spares, but there's always a limit. So just before the end of the season I was asked to fix approximately 20 of the phones. It didn't take long at all, and I was happy to do so. We then had plenty of phones for our final two performances.

Crowd Response

The reaction was amazing. Nobody outside the band knew about the phones (aside from my parents, who watched us build them) so when they lit up the field at out first performance with them there was an audible gasp from the crowd. They were an immediate hit. After the season ended, I fixed a few more and the band director sold the phones to another band to recoup some of the cost. I have no idea what happened to them after that.

The video doesn't do them complete justice, but they're still slightly visible. Their first appearance is at 3:36, though it's easiest to see them at at the end of the show, around 8:08. I never saw them from the crowd (since I was on the field), but I was told they were clear as day- the video just doesn't pick it it too well under the stadium lighting.