David Kubal Example products

radio engineer

Selected Contributions

This section highlights products developed by other companies to which I contributed by designing and developing specific subsystems, either as an employee or as a freelancer.
Modernisation of P19 radar by Retia a.s.. I did speed optimisation of program subroutines for DSP cluster performing primary signal processing.
Technology demonstrator of multistatic primary surveillance radar with omnidirectional antennas and pseudorandom continuous noise signals made by ERA a.s.. I did various system engineering tasks focused mainly on primary signal processing. Thanks to my former colleague Petra Štukovská for the illustrative pictures, published originally in her doctoral thesis "Algoritmy detekce radarových cílů".

Custom Products

This section highlights products developed and manufactured by myself for various customers.
Auxiliary power supply and communication circuits for an integrated mobile UAV protection station. The main components are the Robin Radar ELVIRA radar and the AXIS Q6215-LE camera, built into a Nissan Navara vehicle. Designed and manufactured for AIRSEC s.r.o..
Simulator of electrical distribution networks. The main components are the ITECH IT7815-350-90 three-channel AC/DC power supply, a socket switching network, and a control PC. The hardware was designed and manufactured by me; the control software by BluEmi s.r.o., the company that holds the rights to sell the complete system.
Four-channel electronic balance with outputs to an oscilloscope. A quickly made laboratory demonstrator used to verify a new product idea. Made for Riden Technologies s.r.o..
457 kHz CW airborne receiver with a suspended magnetic antenna for searching avalanche emergency beacons. Designed for Riden Technologies s.r.o. as a demonstrator to prove the concept. The video is for illustrative purposes only and shows a lot of other equipment. I designed only the receiver and the antenna used in the second half of the video.

Exploratory Work

This section highlights products developed and manufactured to prove some concept or because I needed them and they ware not available on the market.
Industrial PC designed as a plug-in unit according to EN 60297-3-101 for 19″ subracks. Design challenges: complete shielding, only 3U height, fanless operation, a backplane used as a heatsink for conductive cooling, 24 V isolated power supply.
Voltage stabiliser for a solar panel and a hydrogenerator on my small sailing boat. Design challenges: no radio interference in the MW frequency range, the ability to supply the boat’s electrical system even in the event of accumulator failure.
Portable solar power system. Input: one or two 385 W solar panels; accumulator: 24 V, 100 Ah, lead-carbon; outputs: DC 24 V  960 W, DC 5 V 15 W, AC 230 V 400 W. Design challenges: small size and fully connector-based interconnections.