Prototype №2 — “Tank”

Our underwater journey continued. The first prototype brought us the results we wanted but we still had a lot of work ahead of us.

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After successfully testing the first prototype with an external speaker, we decided to hide the entire device in one case. But how are we going to fit a huge board, a battery and a bone speaker in a small round case no one had the slightest idea.

Then we printed out all the components on a 3D printer and tried to fit everything in a circle and try to understand what is the right form for their placement. Fortunately, the antenna does not need to be inserted inside yet — it will be external in this prototype.

When it became clear that this is possible, the electronics engineers sat down to develop a round printed circuit board with a hole in the center for the bone conduction speaker. The antenna of course is not going to fit yet, so it will stick out for now.

Right after we designed the second prototype we knew what it should be called. It’s a typical tank!

At the same time our guys began to test the heart of our device — the bone conduction speaker. We ordered a dozen different sizes and capacities and began to check which one gives the maximum power at small sizes.

Having made a choice on a large and quite loud speaker, the engineers inserted it into the case.

We did not know then that such a powerful speaker would consume our entire small battery in 15 minutes :) But so far it was not important because the purpose of this prototype was to fit in a small case not being super autonomous.

The component board was double layered and ordered in China. And a month later we finally assembled the first “Tank”, which by the way worked!

We ran to test it aaaand…the tank did not fire. Range of action — 50 meters. The speaker wheezed like Darth Vader having a cold, and the battery generally refused to support the life of our receiver.

Hmm, it turned out that just assembling a device is not enough to make it work. Debugging has begun. Here go versions — 2.1, 2.3, 2.43. So we got a small army of tanks with different weapons — from a huge black muzzle to a small rectangular gun on the tower. So we got a small army of tanks with different weapons — from a huge black muzzle to a small rectangular gun on the tower.

Finally, our tank troops won — the enemy was defeated, and the tankers celebrate the victory!

The antenna is tuned — it picks up 200 meters in the air, the speaker works reasonably well (but we will change it anyway) and the battery holds for half an hour.

Yes, we may have won this battle, but not the war — we realized that it was just beginning. Let’s move on — the protruding antenna from under the cap still does not inspire anyone, so we say goodbye to the tanks and say hello to …

To be continued.

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