Jarek's Underwater Life

After a longer break, I’m bringing new updates about the AquaSky unit. At the end of September, I completed its software version 1.0.0. It was a long and demanding process that required a lot of time, effort, and new equipment — all within a workspace measuring only 3.6 × 1.3 meters.

Below is a summary of what the unit can do in its current version.

LED Control

• Programmable control of up to 4 independent LED channels in the 12–24 V range.
• Each channel has PWM resolution better than 0.001%.
• Built‑in protection disables the output if the current of any channel exceeds 5.5 A.
• PWM values can be defined using a table with up to 100 time points with 1‑second precision.
• Each point can use either a step or fade transition.

Auxiliary Outputs

• Programmable control of up to 2 auxiliary channels (5 V or 12–24 V) which do not require PWM.
• Time control using a time window with 1‑minute precision.
• Option to define a trigger based on LED current or power, including hysteresis.
• Total available current for auxiliary channels is 0.7 A.
• Integrated overcurrent protection that limits current when the threshold is exceeded (future versions may include extended logic).

Communication

• Configuration and programming through the app using Bluetooth LE (min. 4.0).
• The app allows changing the device name and PIN code.
• If the PIN is forgotten, a Bluetooth settings reset can be performed using the button.

Date and Time

• Date, time, and time zone are set from the control app.
• Automatic daylight saving time adjustment based on the selected zone.
• The time is backed up by a battery, so it is not lost during power outages.

Additional Features

• Operating voltage 12–24 V.
• If the voltage drops below 9 V, the LED channels turn off and reactivate only after returning to a safe range.
• The same protection applies when exceeding 25 V.
• The unit automatically goes to sleep when all LED channels are at zero to reduce power consumption. It wakes up automatically just before activating the outputs.
• Firmware updates are performed through the control app — enabling feature additions and bug fixes remotely.
• The main control button has multiple functions:
  • start / stop the program
  • reset Bluetooth settings (hold 5–10 s)
  • clear storage and settings (hold 10–15 s)
  • factory reset including reverting to the factory firmware (hold 7 s after connecting power)
• The second button is used to wake the unit if it is asleep.

Power Consumption

The following table shows the unit’s power consumption. For comparison, I also include measurements of the TC420 unit:

Manufacturing

Manufacturing the unit is very time‑consuming. I don’t have a production line, so I assemble every component by hand using tweezers and a magnifier.

• Assembling the small components takes approximately 5 hours.
• This is followed by inspection and possible solder joint repairs — another 4–5 hours.
• Then I assemble the large components and connectors, build the enclosure, and perform stress tests and long‑term aquarium testing to verify time stability and set the calibration constant.

I have built two additional units that I’m considering offering for sale. The biggest cost factor is, of course, the time required for manual assembly, so without a production line I cannot compete with “Made in China” prices.

Control App

I spent the last month finalizing the control app. The UWP model is outdated today, so I had to deal with several technical challenges. Nevertheless, I managed to complete a stable version just before midnight on December 31, 2025!

I would like to publish the app in the Microsoft Store, which will require creating a developer account — likely a paid one.