User:Bertrik Sikken

User info Bertrik Sikken
Name	Bertrik Sikken
Nick	bertrik
Tagline	heb ik niet

You can reach me at bertrik@sikken.nl or bertrik@gmail.com

Studied Electrical Engineering at Twente University.

Main interests:

• reverse-engineering things (USB stuff, mp3 players), working on http://rockbox.org
• studying bats and making electronics for recording/listening to bat sounds
• radio stuff, in particular software-defined radio

Projects I work(ed) on (refresh):

	Project Status
FrontDoorDisplay	Abandoned
HabAlertApp	Abandoned
ISSO	Abandoned
IbmPosDisplay	Abandoned
Pico Trackers	Abandoned
RadarOnAStick	Abandoned
WifiLamp	Abandoned
A4PaperDispenser	Completed
BuildStatusTrafficLight	Completed
CJMCU-811	Completed
CO2MeterHacking	Completed
CrawlSpaceSensor	Completed
DecodingLora	Completed
DustSensor	Completed
ElectronicLoad	Completed
EspNowSkip	Completed
Intakefancontroller	Completed
LichtKrant	Completed
LoRaGateway	Completed
LoraBatBox	Completed
LoraWanNode	Completed
MHZ19	Completed
MainsFrequency	Completed
MiniSTM32F103ZE	Completed
PowerLight	Completed
RC522Hacking	Completed
RevRadio	Completed
STM32	Completed
Secure iButton	Completed
SoilHumiditySensor	Completed
StofAnanas	Completed
Stofradar	Completed
TTNHABBridge	Completed
VINDRIKTNING	Completed
ZigbeeCoordinator	Completed
Sensor-data-bridge	Completed
AntiLost	In progress
AudioMoth	In progress
CubeCell	In progress
EspAudioSensor	In progress
Esp32cam	In progress
FMCWRadar	In progress
Karaburan	In progress
LoRa-E5-mini	In progress
LoraWanDustSensor	In progress
MainsFrequency2.0	In progress
Msi2500SDR	In progress
MysteryLidar	In progress
Sim7020	In progress
StereoBatRecorder	In progress
... further results

Old project ideas:

• Use two old satellite dishes to allow speech to be transferred over some distance
  • Figure out focal point
  • Create some kind of dish mount

Project ideas for 2016:

• Understand LoRa modulation a bit better, ultimate goal is to create an SDR algorithm to decode LoRa without the need for dedicated LoRa hardware. This could be useful when tracking HABs transmitting LoRa for example.
  • Apparently the modulation used is chirp spread spectrum
  • See also this Semtech application note: http://www.semtech.com/images/datasheet/an1200.22.pdf
  • A picture of some reverse engineering already done: http://leobodnar.com/balloons/files/LoRa/LoRa-2.gif
  • Some existing code for a lora plugin for sdrangelove: https://github.com/hexameron/rtl-sdrangelove/tree/master/plugins/channel/lora

New project ideas:

• Create a RFM69HW TNC, based on code by flok
  • Remove 'flok' framing, make it comply with KISS protocol
  • Use 'infinite' package length mode to send typical TCP/IP frames (1500 bytes)
• Create a 'HabAlert' android app, see HabAlertApp
• add opus audio codec support to squeezeboxserver and/or squeezelite
  • an opus web radio stream already seems to be redirected to the client, but squeezelite crashes on it
• create code for remote control of my ZwaaiLicht
  • implement wireless protocol for the NOMZ message ("\x4NOMZ") on address 0x66996699L (no ack)
  • possibly implement a more capable protocol on a different pipe (with ack, learn about extra pipes on NRF24L01+)
  • possibly split control of the light and the motor
• Experiment with an ESP8266 serial-wifi module, WiFiBat project plan:
  • attach an ESP8266 to a migrating bat and program it to record a list of wifi APs every day, so the location over time can be determined from the AP-list (use Mozilla geolocation service to convert from AP-list to location), main challenge: keep weight and power consumption low.
• Create better algorithm for detecting heartbeat using this optical heart beat sensor: sample the analog signal at 100 Hz and do an autocorrelation to get a continuous estimate of the heart rate.
• Play around with so-called LoRa (long range) RF modules. These modules have improved range owing to spread-spectrum modulation, error correction and 100 mW RF output.

Laser cutting: I would like to get more creative with the laser cutter, starting with cutting existing designs, for example:

• DONE! -> this trebuchet
• DONE! -> this catapult or the mini catapult
• a cool looking box with gears
• mini marble machine
• DONE! -> bee puzzle
• the MeArm, a simple robotic arm, parts fit on an A4 that can be cut in our Lasercutter.