Perhaps not everybody knows, but in April 2021 we sold the last uECG device from the first batch we made after the Indiegogo one. Naturally, we were optimistic and planned to launch production in April at once, but - you guessed it - not everything went as planned...

Partially it was because in this production run we supplied our own components to the factory and this new method required more time to buy and ship the components (and to research how to supply them correctly). But also because we wanted not only to re-produce another batch, but to make the device more functional. To do this, it was necessary to add / rewrite the firmware and make a component revision.

What has changed?

1. Added a standard Bluetooth connection (BLE). Although the data transfer rate has not changed much, there are fewer lost packets.

2. Added an external antenna for better signal - the antenna on the board was too close to the skin and was not as efficient. Now your heartbeat can be displayed even more reliably! This is a sticker antenna that is connected to the board through an IPEX connector and stuck to the case from the inside, so the device will remain the same size.

3. Added / removed a number of components: namely, removed the optocoupler, changed the power circuit for the nRF52832 to an internal dc-dc, partially switched the voltage to 3.0 V, and changed the method of powering on the device (now the on-off switch only turns on the battery power, but the device itself is turned on by a tact button).

5. Finally pogo pin contacts have small holes in them and won't slide - we have moved them from behind the USB connector to a position which had free space over it on the top side, so we were able to add the holes.

4. These various PCB changes prompted a 3D printed case upgrade (as some elements changed position), and now it fits even better.

6. At last, we were able to defeat power consumption and now our 200mA, 501245 battery will last a whole day!

7. Improved signal data packing for the BLE version (previously, the peak amplitude R in BLE mode could be inaccurate due to the averaging method)

8. Last but not least - the R-peak detector has become even more reliable!

But the most crucial improvements, in my humble opinion, we will share in the next posts.

We're really excited about this new uECG version!