Turtle Rover – Battery pack

In difference to the original Turtle Rover battery I run a custom battery pack in a 6S3P configuration of Samsung 18650-35E cells. That’s 22.2V/10.2Ah in total. The brand new, yet to be released, Texas Instruments BQ40Z80, a 2 to 7 series battery pack manager with impedance track gas gauge, takes care of the entire pack. Its protection and balancing features guarantee safe handling of this energy source. The SMBus interface allows readout and indication of all battery lifetime parameters in the Rovers mission control software.

Battery pack management board based on Texas Instruments BQ40Z80.

Battery pack management board based on TI BQ40Z80.

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RF Amplifier 27dBm – Results

Some measurement results for the 27dBm RF amplifier that was descripted in an earlier post. Results are shown for two builds, without and with additional SAW filter.

27dBm RF Amplifier builds

27dBm RF Amplifier builds

27dBm RF amplifier normalized

Frequency range 300MHz – 3GHz. Input -20dBm, normalized to 0dBm, hence coax cables and output attenuator are calibrated out of the measurment loop.

27dBm RF amplifier gain

Gain over frequency range 300MHz – 3GHz.

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Laser Distance Meter Hack – Type 2

Here is a second description as follow up of my first post hacking a laser distance meter for Arduino Nano support.

The second device looks identical to the first one from outside. But there is a different board inside. That fits to a report of one blog commenter who is trying to modify his own device as well. In sum we got three devices with three different board layouts so far, apparently looking the same from outside.

Board front side.

Board front side.
With space for a wireless add-on board, Bluetooth maybe?

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