Archive of my old articles
Radio technology is now more than 100 years old and this is a pretty long
history. Although it should be possible to learn radio technology much
faster, every good radio engineer should experience the whole story. In other
words, everyone should start with the famous Tesla coil, then build something
simple with vacuum tubes and germanium transistors before getting to the
sophisticated semiconductors we have today.
Here I decided to publish most of my old articles for at least two reasons.
First and most important, older and/or tutarial information can only be made
available to young people via internet, since paper copies of magazine
articles are no longer available. Second, it makes sense to study one's own
history just to avoid repeating the same mistakes already made in the past.
I wrote my first article while I was 15 years old. The article was published
in 1975, in the June issue of Radioamater, the official magazine of the
association of radio-amateurs of Yugoslavia. The text of my article was
carefully translated from Slovenian into Serbo-Croatian, the latter being
understood by most people living in former Yugoslavia. Unfortunately
schematics were frequently carelessly redrawn introducing errors in almost
all magazines and their editors sometimes stripped out some information.
Therefore I decided to publish here my original manuscripts wherever
possible. If the same article was published in more than one language,
priority was given to the Slovenian version. Some information could not
be retrieved, since there were no photocopiers available back in 1975. My
manuscripts were initially retyped making a few copies with carbon paper.
Drawings were simply redrawn if a copy was required.
Initially I did not have a radio-amateur callsign. Afterwards my articles
were published under three different callsigns: first YU3UMV, then YT3MV
and finally my present callsign S53MV. Since our typists only understood
Slovenian, I had to neatly rewrite by hand all the manuscripts in Italian
and/or English.
Since computers became available, I used in total five different printers.
My first attempts were made on a big mainframe computer with the associated
line printer. Then I interfaced an old mechanical teletype to my home
computer. Of course the teletype used Baudot with lower-case letters only!
Finally I got a real needle printer, followed by two laser printers.
Considering all these different formats, the only practical solution was
to scan all the original paperwork, regardless whether it was hand written,
typewriter carbon copy, mainframe printer or any of my home printers.
Drawings were scanned in black-and-white while photos were scanned with
gray levels. All the scanned information was finally assembled together
into PDF files. At the end, a short English abstract was added to all
articles in Slovenian, Italian and English.
Many of my more recent Slovenian articles, written in the timeframe
1990-2000, were assembled together in two books: Beacon 99 and
Digitalni mostovi 2000. Since these two books are no longer available
in printed format, I published their PDFs on my main homepage. Both
books still contain useful information about weak-signal amateur radio
(Beacon 99) and about our amateur packet-radio network (Digitalni
mostovi 2000).
A third book on amateur satellite activities is certainly missing.
There are several reasons. The most important is the total failure
of the AMSAT-P3D satellite due to several independent design flaws.
Free access to analog and/or digital weather-satellite images is
no longer available: except for the NOAA polar orbiters, data from
all other weather satellites is now being encrypted. Professional
satellite point-to-point links and broadcast are being replaced by
optical fiber. The only remaining satellites with free access seem
to be the GPS and GLONASS navigation satellites.
The originals available were not always in the best possible
condition. This is especially true for the masters for the
printed-circuit boards. Before 2000 these were all analog drawings
made with transferable symbols and adhesive tapes. The latter
deteriorate quickly with time. Although I tried to do my best
while scanning, some PCB masters may no longer be useful.
PLEASE DO NOT ASK ME TO SEND YOU BETTER PCB MASTERS! I ALREADY
PUBLISHED THE BEST COPY I HAD AVAILABE ANYWHERE ON MY HOMEPAGE!
Future articles are unlikely to ever appear on this list.
In fact, today most of my articles are first published on the web
on my homepage, since there is nothing comparable to the power of
the allmighty internet search engines. Only afterwards they may
get printed somewhere. On the other hand, presentations are only
seldom published in conference proceedings. Therefore the web is
the ideal place to publish the variuos slides in full color.
Available articles in PDF:
VHF AM-FM sprejemnik AF55 (SLO-1975)
My first published article: simple VHF receiver with very low IF, mainly for FM broadcast
Primopredajnik za CW in SSB (SLO-1976)
CW and SSB transceivers for 3.5MHz, unpublished, 2nd prize in a design competition
FM WALKIE-TALKIE (SLO-1977)
Single-channel 144MHz FM transceiver
Sprejem slik z meteoroloskih satelitov (SLO-1978)
Reception of weather-satellite images on 137MHz
FM voki-toki - nova verzija (SLO-1978)
Single-channel 144MHz FM handy-talkie
SSB-FM primopredajnik za 144MHz (SLO-1979)
SSB-FM transceiver for 144MHz with VFO & frequency counter
VHF FM sprejemnik (SLO-1980)
Wideband FM tuner, broadcast band and 130-160MHz
HRPT una nuova meta (ITA-1981)
NOAA HRPT image reception and demodulation
Preamplificatore a basso rumore per la banda S (ITA-1981)
LNA for 1.7GHz with a CFY11 GaAsFET
Convertitore per la banda S (ITA-1981)
Downconverter for 1.7GHz with half-wave, center tuned cavities
FM voki-toki za 430MHz (SLO-1981)
Single-channel 430MHz FM handy-talkie
Miniaturni 144MHz sprejemnik (SLO-1982)
Simple 144MHz SSB (DSB) receiver
Un prescaler economico per 1.4 GHz (ITA-1982)
Inexpensive 1.4GHz, divide-by-64 prescaler with the S0436 chip
APT scan converter (ITA-1982)
Weather-satellite image scan converter, TV monitor output, 128x128 resolution
RX sintetizzato per i 2m (ITA-1982)
Synthesized VHF FM receiver, 12.5kHz step, theory of charge-pump frequency-phase detectors
A digital scan-converter for weather-satellite images (ENG-1982)
Weather-satellite image scan converter, TV monitor output, 128x128 resolution
2. Frame memory PCB YU3UMV002 (ENG-1982)
New digital board for the APT scan converter, 256x256 resolution
A false-colour PAL modulator (ENG-1983)
Transforms the gray-scale output of the APT scan converter adding false colours
Transverter za 23cm u mikrostrip tehniki (SLO-1984)
Microstrip transverter 1296MHz/144MHz including VOX and antenna switching
SSB/CW primopredajnik za 144MHz (SLO-1985)
SSB/CW transceiver for 144MHz with 100Hz step synthesizer
VHF reflektometer (SLO-1985)
VHF reflectometer with stripline directional coupler
YU3UMV transverter 144/432MHz (SLO-1986)
Transverter 432MHz/144MHz including VOX and antenna switching
CW filter za 10.7MHz (SLO-1986)
CW xtal filter for the SSB/CW transceiver for 144MHz
Microstrip transverters for 23 and 13cm (ENG-1986)
Microstrip transverters 1296MHz&2304MHz/144MHz including VOX and antenna switching
A Ku-band low-noise downconverter for satellite-TV reception (ENG-1986)
LNC (feed, preamp and downconverter) for 11GHz satellite-TV reception
Satellite-television receiver indoor unit (ENG-1986)
Analog-FM satellite-TV receiver 800-1800MHz
Sprejemni konverter 29MHz (14MHz) na 145MHz (SLO-1987)
Receiver converter 29MHz(14MHz) to 144MHz
A C-band low-noise downconverter for satellite-TV reception (ENG-1987)
LNC (feed, preamp and downconverter) for 4GHz satellite-TV reception
Digital Signal Processing Techniques for Radio Amateurs (ENG-1988)
Theory of DSP filters and other circuits
Un modem FSK universale (ITA-1988)
Simple FSK modem for RTTY and packet-radio
Design of a DSP computer for radio-amateur applications (ENG-1989)
Circuit diagrams of the DSP computer
Construction and use of the DSP computer (ENG-1989)
Construction hints for the DSP computer
Amateur-radio Applications of the Fast Fourier Transoform (ENG-1990)
Theory and practical applications of FFT spectrum analyzers
Druzine TTL digitalnih integriranih vezij (SLO-1990)
Families of 74xxx TTL logic circuits
Umetni sateliti, vesoljska tehnika in radioamaterji (SLO-1990)
Satellites and amateur-radio activities
Vesoljski vremenko: (1) Polarni vremenski sateliti (SLO-1991)
Polar-orbiting weather satellites
Vesoljski vremenko: (2) Geostacionarni vremenski sateliti (SLO-1991)
Geostationary weather satellites
Amaterska sprejemna postaja za vremenske satelite (SLO-1991)
Amateur receiving station for weather satellites
Praznilec in merilnik kapacitete NiCd akumulatorjev (SLO-1991)
Automatic discharger and capacitance meter for NiCd batteries
Mosticni reflektometer 100kHz-2.5GHz (SLO-1992)
Bridge reflectometer for 100kHz-2.5GHz
Kaj bi radioamater moral vedeti o VF vodih? (SLO-1992)
Tutorial on RF transmission lines
Tranzistorski mocnostni ojacevalnik za 145MHz (SLO-1992)
Transistor power amplifier for 145MHz
Dvostopenjski predojacevalec za L podrocje (SLO-1992)
Two-stage GaAsFET LNA for L-band (1.3-1.7GHz)
Elektricni sum in elektronski izvori suma (SLO-1993)
Electrical thermal noise and electronic noise sources
Intermodulacijsko popacenje (SLO-1993)
Theory of intermodulation distortion (IMD) and practical examples
Lecher-jev vod (SLO-1993)
Lecher line as wavemeter
Sprejemnik za frekvencno podrocje 2.4GHz (SLO-1993)
Circularly-polarized feed, LNA and downconverter for 2.4GHz
Avtomat za praznicni drevescek (SLO-1993)
Three-channel Christmas-tree light show
Helij-neonski laser (SLO-1994)
Construction of HeNe lasers and simple power supply for a HeNe tube
Vijacna antena (helix) z osnim sevanjem (SLO-1994)
Theory, operation and design of end-fire helix antennas
Sestavljanje krozne polarizacije (SLO-1994)
Obtaining circular polarization from two linearly-polarized antennas
Akusto-opticni modulator za laser (SLO-1994)
Theory and design of a simple acousto-optical modulator
Popravek Kepler-jevih elementov iz meritve Dopplerjevega pojava (SLO-1994)
Correction of Keplerian orbital elements from Doppler-shift measurements
Slikovni ojacevalniki in pretvorniki (SLO-1994)
Image-intensifier tubes and image-converter tubes
Kremencevi kristali, kristalna sita in oscilatorji (SLO-1994)
Quartz crystals, crystal filters and oscillators
Sprejem APT-WEFAX slikic s satelita Meteosat (SLO-1995)
Linearly-polarized feed and downconverter for 1.7GHz
UKV FM sprejemnik za vremenske satelite (SLO-1995)
130-160MHz FM receiver with 30kHz IF filter and 5kHz-step synthesizer
Izboljsani napajalnik za helij-neonsko lasersko cev (SLO-1995)
Improved power supply for a HeNe laser tube
Johannes Kepler in Keplerjevi elementi (SLO-1995)
History about Johannes Kepler and description of the Keplerian orbital elements
PLL sintetizator za konverter za L podrocje (SLO-1995)
Synthesized LO for the 1.7GHz downconverter
Satelitsko radarsko slikanje zemeljske povrsine (SLO-1995)
Theory of satellite radar imaging
Vrste kondenzatorjev in njihova pravilna izbira (SLO-1995)
Types of capacitors and their correct selection
Mehko spajkanje v elektroniki (SLO-1995)
Soft soldering in electronics
Satelitski sprejemnik za 1.7GHz (SLO-1996)
1.7GHz receiver including data interface for NOAA HRPT
Tehnika mikrotrakastih vodov (SLO-1996)
Theory and practical (passive) microstrip circuits
5-elementna Yagi antena za 435MHz (SLO-1996)
5-element NBS Yagi for 435MHz
Vesoljski nadzornik moci z imenom LEILA (SLO-1997)
Description of the LEILA module onboard the AMSAT-P3D satellite
Piramidna lijaka za 5.7GHz in 10GHz (SLO-1998)
Pyramidal horns for 5.7GHz & 10GHz
Predelava mocnostnega ojacevalnika za 145MHz (SLO-1998)
Modification for the 145MHz power amplifier
Lastnosti in oznake keramicnih kondenzatorjev (SLO-1999)
Properties and markings of ceramic capacitors
Aktivna antenska kretnica 1.7GHz/2.4GHz (SLO-1999)
Active antenna-branching filter for 1.7GHz/2.4GHz
Kako narociti kremencev kristal? (SLO-1999)
How to order a quartz crystal
Gradnja in ozivljanje postaj z nicelno medfrekvenco (SLO-2000)
Construction and tuning hints for the ZIF-SSB transceivers
Predelave SuperVozlja in popravki TNCja (SLO-2000)
Modifications of the SuperVozelj and corrections for the megabit TNC
Amaterska izdelava tiskanih vezij (SLO-2001)
Amateur manufacturing of printed-circuit boards
Amaterski packet-radio in internet (SLO-2001)
IP over AX.25 using SLIP thorough a SLIP-KISS TNC
Rezonatorsko sito za 23cm (SLO-2001)
3-stage cavity filter for 23cm
Izboljsani PSK demodulator za 1.2Mbit/s PSK RTX
Improved BPSK demodulator for the 1.2Mbit/s packet-radio RTX
Kristalni oscilatorji in njihova zamenjava (SLO-2001)
Discrete replacement for (packaged) crystal oscillators
Installing an ATC Transponder on a Small Aircraft (ENG-2004)
ATC-transponder power budget and selection of a suitable antenna
Ne-Brezhibni protokol (SLO-2010)
A simple communications protocol, hardware & implementations
Programska oprema ATNC/EATNC inacica h91/e45 (SLO-2010)
Operation & commands of ATNC/EATNC firmware h91/e45
Available presentations in PDF:
Digitalno procesiranje signalov za radioamaterje (SLO-1988)
Practical digital (audio) signal processing for radio amateurs
DSP Using General Purpose Microprocessors (ENG-1988)
DSP modem, terminal and tracking program for the JAS-1 satellite
Experimental Reception of the UoSAT-2 2.4 GHz Beacon (ENG-1988)
Reception report and hardware block diagram
Single Frequency Refraction Correction (ENG-1991)
Ionospheric correction using delay & Doppler measurements on L1 GPS transmissions
Radio-amateur applications of GPS/GLONASS satellites:
Using GPS/GLONASS satellites as an accurate frequency/time standard (ENG-1992)
Homemade GPS/GLONASS receiver
A Satellite Receiving Front-End for 2400MHz (ENG-1994)
Antenna, preamplifier and downconverter for narrowband, weak signals
Laserske zveze (SLO-1995)
HeNe laser tube, acousto-optic modulator and image intensifier/converter tube
1.2Mbit/s SuperVozelj packet-radio node system (ENG-1995)
S5 packet-radio-network node computer (Motorola 68010), modems and radios
Uporaba novejse tehnologije za radioamaterske mikrovalovne radijske postaje (SLO-1996)
Theoretical discussion of direct-conversion and zero-IF (Weaver) SSB transceivers
23cm PSK Packet-radio TRX for 1.2Mbit/s user access (ENG-1996)
Simple Zero-IF BPSK transceiver (1W) for megabit packet-radio links
13cm PSK Transceiver for 1.2Mbit/s Packet Radio (ENG-1996)
2360MHz BPSK transceiver (0.5W) with double-conversion (75MHz/10MHz) receiver
Nacrtovanje SSB radioamaterskih radijskih postaj (SLO-1997)
Design of zero-IF SSB transceivers for 23cm and 13cm
Spektralni analizator v samogradnji (SLO-1998)
Homemade RF spectrum analyzer with tracking generator and other accesories
Razvoj visokofrekvencnega spektralnega analizatorja (SLO-1998)
Design of a RF spectrum analyzer with tracking generator and other accessories
Preklop sprejem/oddaja na UKV podrocju (SLO-1999)
Practical solutions for RX/TX antenna switching at VHF
Svetilniki Beacon 99 (SLO-1999)
Microwave radio beacons for the Beacon 99 Phare project
Izbira modulacije za packet radio (SLO-2000)
Theoretical discussion about different modulation formats in packet radio
A simple TNC for megabit packet-radio links (ENG-2000)
Fast KISS TNC with 68HC000 CPU and Z8530 SCC generating vectored interrupts
Conjugated-Phase Antenna/Transponder (ENG-2001)
A proposal for a satellite antenna/transponder self-focussing array
An improved BPSK demodulator for the 1.2Mbit/s packet-radio RTX (ENG-2001)
BPSK demodulator performance and different Costas-loop designs
Tehnika za frekvence nad 20GHz (SLO-2002)
Semiconductors and techniques for frequencies beyond 20GHz
Radijske komunikacije v letalstvu (SLO-2003)
Radio communications and radio-navigation aids in aviation
Sodobni VF/mikrovalovni tranzistorji (SLO-2004)
Theory about modern RF/microwave (power) transistors
Intermodulacijska popacenja ojacevalnikov (SLO-2006)
Intermodulation distortion in RF amplifiers
Pristajalni radarski visinomer za mala letala (SLO-2006)
Landing radar altimeter for small aircraft
Toplotni sum v radijskih zvezah (SLO-2007)
Thermal noise in radio communications
Konstrukcija frekvencmetra (SLO-2008)
Design of a frequency counter
Letalski radarski visinomer (SLO-2008)
Aviation radar altimeter & vertical navigation radar
Optical-fiber time-transfer & synchronization systems: advantages, physical limitations and practical implementations (ENG-2009)
High-accuracy clock distribution over compensated optical fiber
ESMO RADAR proposal (ENG-2009)
A RADAR payload proposal for the European Student Moon Orbiter
Kratka zgodovina nasih poskusov z umetnimi sateliti (SLO-2009)
Short history of our experiments with artificial satellites
DDS VF izvor (SLO-2010)
A simple DDS RF signal generator with AM, FM and other modulations
Ne-Brezhibni Protokol (SLO-2010)
A simple communications protocol for lossy radio channels
Ne-Brezhibni Protokol (2) (SLO-2010)
A simple communications protocol & hardware for lossy radio channels
Nadgradnja omrezja za Ne-Brezhibni protokol (SLO-2011)
Network upgrade and other developements of the NBP
Megabitna BPSK radijska postaja za 430-440MHz (SLO-2011)
An 1.2Mbps BPSK radio transceiver for 430-440MHz
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