- documenting radiation measurements (video, 4.5 Mb) of thorium nitrate impregnated lamp wicks (25.05.2010)
- homebrew Geiger counter based on article by Matti Granstedt (nocall), "Elektroniikka ja Automaatio"-magazine 3/1984 and 11/1984 Ammattilaisen Geigermittari)
- OK, so I had to dive into some mechanical engineering (906k) in between, when my A1 laser printer simply failed on me, this time fortunately only a siezed electronic clutch
- here is a photo of the Radio Amateur Technology Society Honorary Member 2007 plaque - if you may call it such - oh yes, that crowbar is solid titanium ! (17.06.2008)
- packaged the fabulous SDR-IQ (no affiliation) DSP radio into some recycled NMT900 mechanics - wish I could afford, say, 10 SDR-IQ's ;-) (10.04.2007)
- my simple 50 W solar panel dump regulator (76k) before test installation (20.04.2006)
- my 2.5 kW/4.5 kWh UPS (87k) system for the oil burner, circulation pumps, ham radio, fluorescent lighting and PC server (31.01.2006)
- a compilation of the current Finnish microwave & millimetrewave distance records (24.07.2002)
- a 10.7 MHz -> 30 MHz converter for interfacing my ICOM R-7000 to noise test equipment
- my 3 meter 2 meter antenna experiment (emergency setup for contest) - in Finnish
- here you can find some notes on modifying the Fujitsu FMC080901-70 power amp to 1.3 or 2.3 GHz (in Finnish)
- microwave band expeditions to good locations and even some contesting too...
- Magnetometer for indicating possible Aurora Borealis ( an example: OZ6ABA ( 152k ) in radio aurora on 144 MHz SSB )
- here you can find a somewhat underdeveloped version of my HP41C dish gain/focal length/beamwidth calculator...
- a basic freespace attenuation calculator for the HP41C
- a basic noise floor calculator for the HP41C
- 10 MHz secondary frequency reference ( 68k ) using TV signals ( something in Finnish here ).
- P3D satellite X-band transmitter IHU simulator
- a DC - 12 GHz microwave power meter ( 70k ) for -10 ... +25 dBm levels
- CCD camera adaptor for my 10.5 cm reflector telescope
- prototype broadband gain equalized amplifier ( 73k ) with fault alarm
- BIG file: loads of prototyping different RF & Microwave circuitry !
- electronic fish float
- automotive burglar alarm
- electronic mole deterrent
- homemade 500 MHz spectrum analyser ( 53k ) with 70 dB spurious free dynamic range
- for comparison, screenshots from a commercial digital SPA, my HB SPA with a 15 MHz analogue CRT display and with a 15 MHz 6k point digital CRT - who is the winner ?
- a decent complex spectrum display needs bandwidth (a CRT) and plenty of sampled data with it all brought o the CRT - sampling rate is almost irrelevant
- analogue PAL B/G signal off-air: 1 MHz/div, 10 dB/div, 20 ms/div, RBW 200 kHz, 600 points/div (!), sample rate 500 kHz, trigger: blanking pulse
- peak sync power -12 dBm, analogue aural carrier at +5.5 MHz, -13 dB, digital NICAM at +5.85 MHz, -20 dB
- Geiger Mueller ( 65k ) counter sensitive to beta and gamma radiation
- putting together an OH-TNC2 that I later used for Finlands first 10 GHz mobile packet radio experiments with OH2BSH
- NICAM digital stereo TV sound/video receiver ( 40k ) with analogue OIRT and PAL B/G sound systems too
- a modification to the IC202S transceiver to use it as a 10.7 MHz SSB/CW exciter for testing the P3D X-band TX
- two and four channel meteor scatter recordings of 144 MHz beacons
- here you can also find the dimensions for parabolic dish dipole feeds (31k) for five different ham microwave bands
- and here is a photo (32k) of OH2AXH's beautiful tropo dish feeds for 1.3, 2.3, 5.7 and 10.3 GHz.
- Morsezeichengeber, a real hardware, non-solid state CW keyer, notes in Finnish
