Ralph Holland: Development Experience

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Note that I like learning and keeping abreast with technology, and hold CTO and CEO positions in a few companies.

credentials

• BSc (UNE) 1975 - 1979
• Dip Ed (UNE) 1975 - 1979
• Dip Com Sc (UNE) 1979
• MIEEE TO - to 2020
• MACS (Snr/CP) - to 2020
• Amateur Radio operator ex VK2ZZB (NSW) since 1975, now VK1BRH (ACT) - advanced class licence since 1990
• Private pilot aircraft (Jan 2004), with: Command Instrument Rating, NVFR, CSU, retractable, tail-dragger, and twin-engine endorsements.

Period	Role	Application	Technology
Aug 2023	systems administrator	Developed (repeatable) procedures for working on operational/bootable Linux disks to clone to/from: RAW guest VM disk/images re-partition the images re-factor file systems modify /etc/fstab mount points perform apt update of debian releases via chroot bootstrap install grub for both: MBR legacy EFI boot from the RAW or VM guest images replace kernel/initramfs convert to/from RAW disk image virtual disk images for deployment or testing. These procedures were used to migrate and upgrade a Debian 10 unifi-video NVR to Debian 12, and with a different target partitioning scheme, to permit things like faster Operating System image backups and migration to larger/smaller disks. The next step will be to use these design notes to develop declarative data/scripting that drives an update platform written in rust, and to port that application to run on any operating system. Think of this as a glorified gparted that knows exactly how to partition while preserving the function of the OS image, and other file-systems on the updated disk.	LVM Linux Kernel file system mounts apt chroot
Aug 2023	network engineer	Designed and developed a web-scripting language and web-scripting engine (using playwright API under the covers) to login to the corporate gateway/router web-server and restore all critical configuration for the network operations. This project was conceived because iiNet has periodically remotely factory reset the gateway to default configuration several times now (presumably when doing firmware updates and usually late at night). Formerly requiring me to manually restore many attributes through the only option, a web-browser interface. The web-scripting software is running as a cron job and it automatically restores the gateway configuration after it detects a factory reset of the gateway/router.	JSON used for web-script language playwright API node-js used for the platform chrome browser API HTML knowledge
Jun 2023	security engineer	hosted separate VPN tunnels in a corporate edge-router (firmware) for use by: mobile devices, office devices, and experimental devices. Installed associated IP filter rules to provide DMZ isolation from the corporate network and to restrict access to the www access only for mobile iOs devices. Developed other VPN endpoints that can provide access to the corporate network for corporate equipment and for remote access. I set this up to use for our holiday in Vanuatu - we now permanently run with the mobile device VPN on our devices.	Mikrotik Router Os
Apr 2023	software/security engineer	developed a network travel companion/road-warrior dual-channel Wireless Access Point that provides various web-browser configurable router/bridge (10) configurations for connection to motel wired or wireless networks to provide safe www access for mobile equipment while travelling. Written in node-js using systemd-networkd, supplying a web-server hosted on a raspberry pi running standard Debian (not openWrt). This should probably be migrated to rust.	debian 11, systemd-networkd, node-js for the web-server raspberry pi
Nov 2022 - Apr 2023	architect	extended the node-js repository mirror with handlers to handle various repositories: Debian apt, node npm, Java mvn, Perl CPAN, R CRAN, Python PyPi, gnu mirrors. (About to investigate a rust cargo mirror.)	Perl, C++ node-js, dynamic HTML css.
Sep 22	computer and electronics trainer	I am familiar with a variety of computer and electronics hardware. We formed https://regional-training.org on 20 Oct 2023 to start passing on our knowledge to the younger generations. https://regional-training.org	electronics computing instruments soldering programming design training remote learning remote collaboration
Oct 22	electronics technician	Repaired my broken Synology NAS. https://publications.arising.com.au/pub/Synology_DS1515%2B_repair	electronics
Nov 22	security engineer	declarative performance monitoring.	node-js chart.js dynamic HTML various linux synology OS
Apr 2021	System administrator backups	Wrote scripts and services to automatically backup data for: all mariadb databases all mediawikis gitblit repositories nexus respositories	bash rsync cron
Mar 2021	Security engineer Build from source	designed and developed node-js read/write repository server and mirror for Debian apt repositories. Server supports renaming-releases (/<os>/dist/<release>, generating new release, metadata parsers are provided for: .deb, .dsc. Release, Sources, Packages file for metadata analysis. (TBD: Index files to be generated from database on HTTP GET. apt-ftparchive is currently used to regenerate Release files but will be replaced via metadata processing when finalised.) Integrating Build from Source scripts to use the local read/write repository server.	node-js dynamic HTML css
Nov 2021	Architect	developed architecture for environmental monitoring using modbus and IP. Solutions: node-red flows, grafana, influxdb and MQTT server - modernising modbus to IoT like provisions.	node-red node-js C++
Oct 21	Architect	designed distributed listsd processing servers to scan various security logs and maintain black and white lists that are uploaded by my corporate edge-router to block attackers. listsd is written in node-js, and is distributed across various servers and can scan logs such as: /var/log/authn.log, /var/log/fail2ban etc to identify attacker IP addresses and maintain lists. MQTT is used to keep white-list and black lists in lock-step asynchronously in all distributed listsd servers. The router periodically obtains list deltas or full lists via the listsd HTTP server (on any server). These data may be obtained as lists, or as script that can then be executed by the router firmware to update it's lists.	MQTT node-js scripting cron / bash Mikrotik Router Os Cisco router ipTables
Oct 21	Systems engineering	replaced all the SLA batteries in the corporate UPS. designed battery bank and extended the UPS with Extension Battery Module mode to 15 hours of standby	electronics system engineering
Sep 2021	developer	implemented mqttd: a resiliant mqtt service running on Linux	node-js mqtt broker code
Apr 2021	Security Engineer Arising Technology Systems	Evaluated and installed a roll-your-own IP security camera system using COTS IP camera and OpenSource NVR. I secured the camera network via my edge router filter rules to prevent cameras from accessing the www and phoning home. I used Reolink RLC-510/410 IP cameras connected via a PoE switch and captured with Shinobi - an Open Source (node.js) NVR deployed on an Intel NUC. Shinobi performs motion detection and recording. Security Analysis was performed with a pcap capture from my edge-router and using Wireshark for packet inspection which informed my filter rules for the camera gaols. The goal was to provide a secure corporate integrated camera security system network that prevents infiltrations.	intel NUC nginx Debian 11 reolink IP cameras Shinobi node-js
Feb 2021 - Mar 2021	Systems engineer	Developed a watchdog server based on a raspberry pi SBC that is used to supervise all corporate networking and critical server infrastructure. Equipment is recycled when the equipment cannot be probed. Probes cover the network edge-router, network switches, security cameras, NAS, two NTP servers, VTC server, web-servers and other critical infrastructure, including probing access to DNS. Network equipment is recycled when network connectivity fails. The watchdog server manages the power on these equipment, and reset lines on low power equipment. Equipment was designed with electrical and optical isolation and the relays fail-safe to equipment-on, and resets off. The watchdog server also employs a hardware watchdog timer circuit to ensure the watchdog server keeps functioning correctly. This project came about because it became problematic to ring my wife for her to gain access and be instructed to restore services while I was working remotely, like from places such as airports, because the amount of critical equipment keeps increasing in my home office - due to expansion and thanks to covid-19. (It's a self-contained solution rather than using distributed smart-plugs, which could have been incorporated into the design.)	raspberry pi gpio relays python bash cron networking
Feb 2021	Researcher	Investigated Lora and LoraWAN.	web-search raspbery pi HAT
Apr 2020	Systems admin	I use this for secure VTC with my partners, friends and family instead of using insecure Zoom. This server provides fully encrypted voice and video and interoperates with the Jitsi Meet Apps. See https://jitsi.org/downloads/ developed /@ring web-app that rings in the web-browser when someone else connects to the specified VTC room. People can camp in the /@ring app waiting for a room to ring by using the room name or wild-card name matching. Conveniently a blank room name causes the web-app to ring when any VTC room is connected - thus monitoring the whole VTC server name-space.	jisti-meet node-js java jabber web-sockets HTML css HTTPS UDP Debian nginx Intel-NUC
Apr 2019	Systems admin	Migrated off ALL Windows servers, and re-hosted the following services on Debian linux: LAMP mediawiki https://wiki.arising.com.au https://publications.arising.com.au https://ir-gis.com https://family.arising.com.au https://regional-training.org https://dev.arising.com.au https://corp.arising.com.au https://prop.arising.com.au various web-services https://padme.arising.com.au https://padme.arising.com.au:3004 gitblit nexus	Python 7 mariadb apache httpd nginx gitblit nexus
Nov 2018 - June 2023	HPC Security Specialist Engineer	Security Specialist HPC	various languages and technology.
Nov 2018 - Mar 2019	Consultant	HPC (High Performance Computing), proving security posture and designing Software Security enforcement tools.	various
Mar 2018 - Nov 2018	Architect / Developer	Proto-typed http://ir-gis.com/mediawiki/index.php/MapWorld a 3D GIS VR environment.	Java activemq NASA WorldWind
2018	Systems engineer	Developed a tier-0 GPS stimulated NTP server using chrony and GPS derived 1PPS and raspberry pi SBC that are also feeding flightaware data. I did this because I want more accurate time to improve the precision of multilateration for my own experiments, and for my mobile piaware. The network time from these 1PPS receivers is more accurate than the local university ntp pool at ANU. The only improvement I could realise is to use dedicated hardware that has hardware timestamps in the Network Interface Controller chip - which would further assist the NTP algorithms with correction of network propagation delay and jitter.	raspberry pi GPS module gpsd chrony
Aug 2017 - Dec 2017	Hardware Communications Architect Consultant	Prime contractor deployed at Thales Underwater Systems - Ryde. Architect for the MHC communications system refit. Looked at IP message bus for all connected equipment, including the entertainment systems.	networking IP radios satellite entertainment equipment security systems under-water cameras
2015 - June 2017	Senior Security Developer	KERMIT Attribute Based Access Control and Identity system authentication via LDAP/Directory Services identity verification fine-grained attribute and role-based access control enforcement	LDAP Directory Services JPA Java activemq Oracle SQL SAML xml HTTP/S HTML css
2016	System Engineer	Deployed a few piaware transceivers for contribution to aircraft multilateration. Raspberry Pi and UHF antenna and Software Defined Radio dongles. Deployed web-cam and web-server for runway cameras http://flyoz.ddns.net:8100. These images are fed into OzRunways and AvPlan Electronic Flight Book systems for other pilots consumption (hence the advertising). http://ycwr.arising.com.au http://wcac.arising.com.au http://yscb.arising.com.au http://flyoz.ddns.net:8100	piaware C++ python java lighthttpd
2016	Developer	Fixed faults in SDR software for piAware. piAware C code.	C/C++
Apr 2015 – present	Chief Technology Officer, founding director, N4RC Pty Ltd	Hardware and Software ideas shop.	various such as: C++ java Python Perl rust go node-js HTML Css
2015	Developer	Developed fixed-point DSP SELCAL encode and decode logic for pic DSP.	C++ pic DSP Aviation Amateur radio
2014	RF Engineer	Designed the HF transceiver installation in my aircraft: developed the audio interface circuitry, which included the impedance matching for the microphone input, and its frequency tailoring to eliminate the “boxy” noise caused by the aircraft engine, and designed the audio output impedance matching all with passive components to avoid failure modes. Designed the placement of the antenna and antenna-tuner and the routing of all cables, and the transceiver grounding to minimize interference by and to/with the aircraft avionics. I even designed the antenna shackle mounting arrangement and the stringer-doubler plate with a strain relief rivet to avoid aircraft skin cracking around the feed-through insulator. Radio communications and electronics.	electronics rf design amateur radio aircraft
Apr 2011 – June 2015	Senior Security Engineer	security identity and decision access control systems Jabber, activemq, oracle SQL, JPA, identity management, extensible meta-data extensible Java bitsets Access Control Decision engine embedded API library.	various such as: C++ java JPA SQL SAML XML HTML Css
2011	Engineer	Designer of Seven-of-nine, a Covert Passive Collector for aircraft multi-lateralisation position reporting. (This was designed before the mandate for mode-ES - aircraft extended squitters and before I adopted flightaware.) Hardware UHF Analogue to Digital (direct) receiver and associated digital processing. No local oscillators – to keep it covert.	electronics r.f. engineering microcontroller
2011	Architect/Senior Developer	Developed maritime trackers in Java (after having developed Aviation trackers to cope with 20 seconds of jitter using Kalman filters).	Khalman filters C++ Java mathmatica
2010 - ongoing	Software Architect	Designed and developed IR-GIS ® MapView for displaying vehicle positions, and IR-GIS ® Historical Pullback Server for recording position reports and attributed text in real-time for historical recall and display in MapView. All developed in Java (highly concurrent and performant) https://ir-gis.com https://ir-gis.com/ir-gis/MapView https://ir-gis.com/ir-gis/HPS	java eclipse RCP tycho git leveraging from udig
2010	Senior Developer	Regression Test Bed design and implementation	java
Nov 2009 – 2010	Product Owner	Product Owner (Business Analyst and Customer Representative) for a team of 5 using Agile Scrum development. Defence.	SCRUM
2009	Senior Developer	Developed Kalman filters for tracking aircraft with up to 20 seconds of jitter (Java real-time processing).	bakeoff between: C++ Java
Nov 2006 - Jul 2009	Senior Developer for Production Systems Defence	Vanguard Signal processing (C++), Protocol extraction (C++), Estimation and Correlation (Java), Regression Test-bed development (Java, Ant, Junt, Sql-unit, Cobertura, eclipse RCP and Cruise Control), World Projections (C++). GIS (ESRI), Google KML, and then http://ir-gis. Air Traffic Network decoding of position reports and telex, multi-headed radar fusion and dynamic earth model adjustments.	C++ Java Java eclipse RCP tycho git SQL JavaScript GIS messaging activeMQ
Oct 2005 to Nov 2006	Support specialist	metadata (SQL) and application dev. (C GUI)	C/C++ GUI SQL
Nov 2002 to Oct 2005	Senior Developer/Architect	Workflow Manager Centrelink, Canberra Enterprise web applications interfaced with M204 Transaction processor.	Model 204 TP HTLM JavaScript XSLT XML UML Architect
Nov 2001 - Nov 2002	Senior Developer	DFAT, Forte 4GL (3.0N.9) migration from Unix to Windows 2000/NT and some C++ support.	forte C++
Mar 2001 – Nov 2001	Forte Mentor and Senior Developer	Framework Architect, Performance Analyst - Technology Partners Group.	Forte Web Enterprise Forte 4GL/UDS XML, DOM, Forte/UDS, HTML JavaScript
Jan 2000 – Mar 2000	Architect and Senior Developer	for Thelma, a health-based Java E-commerce project deployed at ICS global (Sydney), whilst consulting to Technology Partners Group, Newcastle.	Java B2B E-commerce development JRun application server, JSP Oracle JBuilder Oracle 8i.
Nov 2000 - Dec 2000	Performance Consultant	CSC Australia Melbourne E-tag tollway project.	Forte 4GL middleware Sun Cluster Oracle 8i database
May 1998 – Oct 2000	Senior Developer and OOD mentor	deployed at DFAT by BHP-IT on ADCNET ER3 release.	Rational Rose UML/RUP, Forte 4GL middleware, C++, C scripting languages.
Sep 1997 – Mar 1998	Senior Developer/Team Leader	Network Protocol and Framework Architect, Air Data Technologies. Embedded Radio Network for remote power metering.	rf knowledge C++
Nov 1997 to present	Managing Director Arising Technology Systems Pty Limited ACN 079 817 342	Information Technology Consultancy. Enterprise Application Development. Management	C++, Forte, C#, Perl Java node-js Python rust GIS development, antenna simulation compiler writing firmware design.
1997	Systems Engineer/RF Engineer	Contributed to a small part of the design of Anzac phased-array radar system (while at CEA) by suggesting that mixed-polarisation was required, because circularly polarized signals are reflected back at the opposite polarisation due to the reflection boundary. Antenna theory	r.f. engineering electronics
1996 – 1997	Amateur Radio Hobbyist	Numerous HF antenna designs and installations that have been published and in use world-wide Amateur Radio. https://wiki.arising.com.au/wiki/Category:Ralph_Holland:Publications	r.f. engineering electronics antenna simulation with NEC2D and NEC4.
Oct 1995 – Sep 1997	Senior Systems Engineer	| CEA Technologies. Mine Hunter communication’s system (hardware).	electronics R.F. systems engineering
1995 - 1997	Senior Systems Engineer	| | Designed and built axial mode helical antennas for NVIS. (Research project at CEA Technologies.)	Amateur Radio R.F. Antenna engineering vector network analysis
1997	Amateur Radio Hobbyist	Built and designed common-mode rejection baluns and filters for LF through to HF.	Amateur Radio r.f. engineering
1996	Sys Eng	Developed FPLA generated RFDS SELCAL.	Electronics.
Oct 1995 – Sep 1997	System Engineer (rf)	Proposed the broad-band RX antenna design for the Mine Hunter.	r.f engineering
1996	System Engineer (rf)	Proposed the broad-band VHF-UHF TX antenna design for the Mine hunter.	r.f. engineering
1996	System Engineer (rf)	Proposed the omni-directional SATCOM antenna design for the Minehunter.	r.f. engineering
1996	System Engineer (rf)	Contributed to the design of the hi-dynamic range common-mode-rejection differential amplifiers for the Mine Hunter broad-band receive antenna.	r.f. engineering
Jan 1996	System Engineer (software)	Debugged the firmware for one of the CEA Technology Software Defined radios (it took me 10 minutes to read the instruction set and 15 minutes to fix it) – the engineer trying to get this to work was causing a floating-point overflow which was causing the DSP to reset and the I/Q audio recovery to have clicks (each time the processor reset).	DSP assembly language
Nov 1996	Project Manager	Integration of Compucat Maritime Message Switch into the Mine Hunter Communication’s system	systems engineering project management
1996	Amateur Radio Hobbyist	Sailor ATU 1500 modifications, Amateur Radio magazine, 1996. https://wiki.arising.com.au/wiki/Sailor_ATU_1500_modifications	r.f. engineering
1995	Amateur Radio Hobbyist	ATU Modification for the Kenwood TS440-S/AT, Amateur Radio magazine, November 1995. https://wiki.arising.com.au/wiki/Modification_for_the_Kenwood_TS440-S/AT	amateur radio r.f. engineering electronics
Nov 1995 – Sep 2007	Systems Engineer	Developed code that performed cable sizing and least-path placement for the Mine Hunter power and signal buses.	systems engineering electronics
Nov 1995 – Sep 2007	Systems Engineer	Selected components for the design of the Mine Hunter telephone hybrid circuit for land-line to ships coms connection. Mine Hunter communication bus telephone interface. CEA Technologies	electronics systems engineering
Nov 1995 – Sep 1997	System Engineer (rf)	Simulated the HF antenna on the Mine Hunter for near-field verification that common-mode choke placements were required on Mine Hunter communication bus and wiring.	Antenna Simulation (Java and FORTRAN) Mine Hunter Systems Engineering.
Nov 1994 – Oct 1995	Flix Group Manager, Designer and Developer	Proprietary 5GL database project	Borland Pascal Borland C++
Nov 1993 - 1994	Software Architect / Project Manager	Developed the replacement (portable) Compucat Maritime Message Switch, thus familiar with defence messaging	C++ et al. ACP-127, Link-11, and Link-16 etc.
1994	Architect	Proprietary Exception replacement mechanism (C++). Architect proprietary memory allocation routines (Pascal) and Memory allocation for microprocessors and IBM/PCs (C++) Compucat Pt Ltd.	C++ Pascal
Nov 1993 – Nov 1994	Project Manager	Compucat Pty Limited. Protocol, Storage and Interface Architect. Compucat’s first C++ and Object Oriented Development. Also first project certified under AS3901.	C++ Object Oriented AS3901 lead/project Solaris Windows
Aug 1993 – Nov 1993	Research Engineer / Senior Analyst Programmer	Developed Fixed and Floating point to integer processor libraries and Z-buffering graphics rendering. Fleetwork trainer kinematics. Fleetwork trainer lead engineer.	Pascal ASM
1993	Architect	Event-driven Multitasking environment for Borland Pascal DOS applications - used as a basis for Fleet Work Trainer program Compucat Pascal/Assembly language	Pascal ASM
1993	Architect	micro-second precision Event Monitor and program performance metering for PC compatibles). Compucat.	Pascal IBM pc Assembly language
Aug 1993 – Nov 1993	Project Controller/Team Leader/Architect	Fleetwork Trainer (used by the RAN and NZ Navy), Compucat.	Pascal Proprietary motion engine. Assembly language.
1990 – 1995	Amateur Radio Hobbyist	Simulated antennas and verified them by building; my specialty was compact and elevated HF ground-plane antennas and NVIS. I have several publications in this regard, and one publication in a per-reviewed paper validating NEC-2D (which was reviewed by the NEC-2D author as it turns out). https://publications.arising.com.au/pub/Ralph_Holland:_antenna_simulation_publications https://wiki.arising.com.au/wiki/Category:Ralph_Holland:Publications	Amateur Radio NEC2D simulation
1991	Amateur Radio Hobbyist	Designed and developed un-powered Voice Activated switches for transceivers, and transceiver links using transformers and MOSFETs that operated without external power supplies.	Amateur Radio electronics r.f. engineering
1990	Amateur Radio Hobbyist	Designed and developed compact 160 m HF antennas for mobile use. Published in Wia magazine.	NEC2D Antenna Simulation Amateur Radio electronics r.f. engineering
1990	Amateur Radio Hobbyist	Obtained unrestricted (full call advanced) Amateur Licence VK1BRH. https://wiki.arising.com.au/wiki/Category:Ralph_Holland:Publications	Morse Code at 10 w.p.m. Advanced Radio theory electronics
Jan 1986 – Oct 1986	Technical Liaison Officer	deployed at Prime R&D Boston MA, by Prime R&D Australia. Proprietary operating system (PRIMOS). developed interpreter extensions developed Prime Information Releases vetted Prime Information IBM Pc releases developed a Prime Information debugger wrote my Ada compiler master's thesis (with-drawn)	Development languages: FORTRAN, PL1/G, SPL, Assembly language INFO/BASIC.
1986	Architect	Designed and developed a new Database interpreter for Prime INFORMATION (PMA) which achieved up to 6 times performance improvement. Prime R&D. Prime 32R Assembly Language	PMA (Assembly language)
1984 – Oct 1989	Senior Software Engineer	Team Leader, Performance Analyst, Prime R&D Australia. Proprietary operating system (PRIMOS) (based on Multix – the precursor of Unix.)	FORTRAN, PL1/G, SPL, Assembly language INFO/BASIC. Prime INFORMATION 4GL database.
1982	Software Engineer	Developed a BASIC interpreter (C), a PDP-11 emulator (PMA), a Z80 emulator (PMA) - using Prime Assembly Language and C language.	C PMA
1980	Architect	Architect of a Semaphore-based operating system for PRIMOS subsequently used for teaching at the NSWIT.	FORTRAN IV PLP
1980 – 1984	Tutor	NSWIT (now University of Technology), Broadway Sydney. Mini Pascal compiler (Pascal), BNF table driven parser (C), Table-driven diss-assembler (PLP), developed an Ada subset compiler in PL1/G - for Primos, developed Primos hardware semaphore emulator - used for student course work Helped port the Portable C compiler to Primos Academic environment tutoring for wide range of subjects.	Tutor - education Mathematics, Assembly languages, COBOL PL1-G C FORTRAN IV FORTRAN 77 Lisp Ada Pascal RPG-II Languages and Processors (compiler theory), Network Analysis, Micro-controller laboratory etc.
1980	Teacher	Qualified NSW Science and Mathematics teacher, Department of Education. (resigned to learn/teach Computing Systems)	Dip Ed (UNE) 1975 - 1979, Education BSc (UNE) 1975 - 1979 Physics, Chemistry Dip Com Sc (UNE) 1979, Computing Science
1980	Amateur Radio Hobbyist	Designed and published high-impedance RF buffer amplifier circuit so I could signal-trace and tune all the oscillators in a HF transceiver that I repaired – without loading the oscillators. https://wiki.arising.com.au/wiki/High_Impedance_Buffer_and_Broadband_Amplifier_for_Digital_Freq._Meters	electronics RadioFrequency design Amateur Radio
1978	Amateur Radio Hobbyist	Obtained Amateur Call sign VK2ZZB. Built amplifiers, transmitters and some transceivers. https://wiki.arising.com.au/wiki/Category:Ralph_Holland:Publications	electronics radio theory
1975	Electronics Hobbyist	Developed V.21 frequency shift-keying 600 baud phone modem, plus V.22 1200 baud tape modem (because I needed one for my computer work).	electronics computing
1972	Electronics Hobbyist	Rewound a 250 volt laboratory variac that had some burnt-out turns on the later half of the winding.	electrical fitting
1970	Electronics Hobbyist	Designed switch-mode Triac power-supplies (regulating the primary main-supply side of the transformer).	electronic design
1970	Amateur Astronomer	Designed and developed a variable frequency inverter drive for synchronous motors used for astronomical telescope tracking.	electronic design
1970	Electronics Hobbyist	Developed Buck and Boost switch-mode power-supplies before the advent of “jungle” chips.	electronic design
1969	Electronics Hobbyist	Rewound a power drill motor armature – because my father's drill blew-up and he said I can have it if I fixed it, and then he showed me how to fix it (my dad was an electrical turner and fitter by trade). Electro-mechanical.	electrical fitting
1967	Electronics Hobbyist	Designed 400 Watt adjustable linear power supply for my father using a large TV transformer and my own-regulator design. Voltage would only boost up by a faction of a volt under a 30 amp load due to the compensation and voltage sense in my regulator design.	electronics
1966	Electronics Hobbyist	Rewinding valve TV mains transformers for power supplies that I designed.	electronics
1961	Hobbyist	Light and Morse Key circuit soldered at home direct to batteries and switches etc and taken to school. My father made me a soldering iron and taught me to solder at an early age.	soldering electronics

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