December 12th, 1901 is certainly a date with a historical relevance in radio transmissions.
In fact, at 04.30 GMT of that day, Guglielmo Marconi succeeds in sending the first transatlantic wireless communication.
Succeeding in this contact, Marconi demonstrate that radio waves transmissions could be transmitted even across the Atlantic ocean.
With this success Marconi, in addition, disproved detractors who told him, that the curvature of the earth would limit transmission to 200 miles or less.
The Facts
The Italian inventor received in St. John’s, Newfoundland, Canada, the letter S in morse code (three dots) transmitted from Poldhu, Cornwall, in England.
Signal Hill, Newfoundland Canada, to Poldhu, Cornwall, England.
Marconi set up a specially designed wireless receiver in Newfoundland, Canada, using a coherer (a glass tube filled with iron filings) to conduct radio waves, and balloons and kites to lift the antenna as high as possible.
The station in Cornwall, England instead was composed by a twenty-four ships’ masts each 200 feet high, and the transmitter was powered by a 32 brake horsepower engine driving a 25 kilowatt alternator.
History says that detractors were correct when they declared that radio waves would not follow the curvature of the earth.
In fact today we know that radio waves had been headed into space from England when they were reflected off the ionosphere and finally bounced back down toward Canada.
Science demonstrated and explained this contact, made thanks to Radio wave propagation, just a few years later.
Therefore thinking in terms of amateur radio logic, we should consider this experiment as the first DX contact ever.
If you are interested in Marconi’s experiments and history, probably you can find interesting arguments and further details about this story here:
If you are not an amateur radio operator, DX could be considered a funny term.
In the amateur radio lingo:
DX is the telegraphic shorthand for distance or distant
DXing is the hobby of receiving and identifying distant radio signals.
It is easy today to build a GPS tracking system for mobile applications that can be adapted to your needs. In fact, it is more accurate to speak of a GNSS (Global Navigation Satellite System) tracker, a term which encompasses the 4 positioning systems or satellite constellations.
Morse Code Decoder for Android based on the algorithms implemented in CW Skimmer. Morse Expert decodes Morse Code audio to text. It is optimized for decoding weak, fading signals in the presence of interference, especially on the Amateur Radio bands. The input audio might come either from the built-in microphone or from another device, such as a radio receiver.
A magnetic loop antenna designed for 14 MHz. This kind of antennas is also known as STL, small transmitting loop and can be an excellent solution when you are not allowed to put antennas on your roof
Remote SDR is a web application allowing to remotely control an amateur radio transceiver between 1 MHz and 6 GHZ. It allows processing of Adalm-Pluto SDR in addition to HackRF or RTL-SD Reception in NBFM, WBFM, AM in addition to SSB Transmission in NBFM or SSB and more
Complete collection of the four main parts of this excellet research on modelling and designing half wave dipole antennas for 40 meters band, covering all aspects beginning from full wave length antennas, to shortened, loaded and reshaped dipoles
SDR control for FlexRadio Signature Series Rig for Apple Mac. FT8 integration, External Software support, Several additional Tools, display as many panadapters and slices your Radio is capable of.
DX Pedition to Galapagos will be active from October 26th to November 7th, from 6 to 160 meters (including Warc bands) on CW, SSB and Digi modes with at least 4 stations on the air at the same time.
VHF Antenna in a Lunchbox, The Magnetic Loop on Two Metres. The two metre magnetic loop is a compact antenna which can easily be hung up under the eaves, the carport, or any other place where space is limited including indoors
How to improve performance of your audio using a home made speech processor. In this article the author describes how to make your own speech processor providing a PCB foil pattern and with a 60mm x 60mm board.
An L-Match tuner is a device that can add either inductance (L) or capacitance (C) to the antenna, bridging that gap between 5000 ohms and 50 ohms, thus matching it to the radio. The L-Match tuner is an extremely useful device that every QRP operator will want to have.
Reflected power and VSWR Metering on Yaesu FT-817, and proper interpretation of real values. The power output meter it is a relative indicator of the antenna match that the radio is experiencing. Reference table and how correctly read the values of the Yaesu internal meter.
Like SOTA, Summits On The Air, Mines On The Air (MOTA) is an opportunity for Ham Operators to get out, enjoy our hobby and bring others (spotters) along for the ride. It is meant to promote the hobby, enjoy the world around us and bring a bit of history into our lives.
The ID-52E, VHF/UHF dual-band digital transceiver, the latest in a long line of D-STAR handportables from Icom will be available from authorised Icom dealers at the beginning of December.
The ID-52E succeeds the popular ID-51E PLUS2 and is the latest Icom model to work on the D-STAR (Digital Smart Technologies for Amateur Radio) network.
What immediately strikes you about this model is its large transflective colour display that makes it easy to see outdoors, even in bright sunlight.
The size of the display has also been increased to 2.3 inches from 1.7 inches on the ID-51A/E.
The ID-52E supports Bluetooth communication as standard.
You can wirelessly connect to Android devices with the ST-4001A/ST-4001I Picture Utility Software, and RS-MS1A Remote Control Software installed.
The optional VS-3 Bluetooth® headset is also available, for hands-free operation.
ID-52E D-STAR Digital Handheld Transceiver Features:
• Simultaneous reception in V/V, U/U, V/U as well as DV/DV. • Waterfall Scope Function • Airband reception is expanded from VHF to UHF (225 to 374.995 MHz). • Can be charged via a micro USB connector. • Audio output has been increased from 400 mW to 750 mW. • The latest D-STAR functions allow you to send, receive and view saved photos on an installed microSD card using only the ID-52E. • Accessories for the ID-51E, including battery packs and microphones, can be used.
In addition to the above, the ID-52E has a variety of other features including DR function with easy set-up, built-in GPS receiver, micro SD card slot, IPX7 waterproof construction (1-metre depth of water for 30 minutes), and Terminal/Access Point modes.
Having many great features, the ID-52E will appeal to not only beginners but for those experienced operators who want to get even more out of the D-STAR network.
Other Features • 750 mW loud audio output power • Improved heat dissipation efficiency for stable operation • DV fast data mode uses data in place of voice frames • QSO log in CSV data format • Accessories for the ID-51E/ID-31E such as battery packs and microphones can be used • DV/FM near repeater search function • Voice recorder function • External DC power jack
In the UK, the ID-52E will be available from Icom Amateur radio dealers from December 2021 with a suggested retail price of £519.99 (inc.VAT).
The new Yaesu dual band FT5DE, 5W C4FM/FM 144/430MHz is a full-featured C4FM handheld transceiver with superior operability and several new sophisticated features.
Despite its compact size (62x34x100 mm), the FT5DR / FT5DE provides a reliable RF output power of 5 W and achieves an audio power of 1 W, optimised for quality audio.
Real Dual Band operation (V+V, U+U, U+V) is available with two independent receivers. Large individual LED indicators for A-band and B-band instantly show the status and communication mode (C4FM or analogue) of each band.
The new FT5D supports simultaneous digital C4FM (standby C4FM/C4FM). Equipped with a rubber protector the FT5D has a robust and shock resistant construction. The waterproof rating is IPX7.
The comfortable size and shape of the completely flat rear body offers an excellent grip for the operator.
A high-resolution display shows the operating band frequency. The colour of the operating band frequency can be selected from white, blue or red. Three keys on the touch panel and seven keys below the display offer intuitive operation. The new TOUCH & GO mode is convenient for immediately starting communications on a frequently used frequency.
Holding down the “PMG” key registers the current display frequency in the primary memory group.
After recording, pressing the “PMG” key will display the reception status of the recorded frequencies as bars on a graph (activity monitoring).
By simply touching the displayed bar, the user can instantly recall that frequency.
The Band Scope function monitors in real time up to 79 displayed channels centred on the current VFO frequency.
The centre frequency can be tuned using the selector knob or by touching and moving the frequency of a displayed channel bar. With the new FT5D, the already popular C4FM digital communication features such as Automatic Mode Selection (AMS), Digital Group ID (DG-ID) operation and Smart Navigation function are available. The FT5D also supports the WiRES-X portable digital node function.
A portable digital node can be easily set up with the new FT5D, a laptop PC connected to the Internet and the optional SCU-39 cable kit.
The advanced features of the new FT5DR/E includes:
wireless hands-free operation using the optional Bluetooth® headset (SSM-BT10); VOX function; automatic memory grouping (MAG); VFO band hopping function; wide-range RX coverage with continuous reception from 0.5 MHz to 999.99 MHz (A-band) and 108 MHz to 580 MHz (B-band); built-in 66-channel high-sensitivity GPS receiver;1200/9600 bps APRS data modem; high-capacity 2. 200 mAh lithium ion battery (SBR-14LI) as standard; voice recording function; reception of simultaneous AM/FM transmissions while monitoring two frequency channels; microSD card slot. The new quick-release case (SHB-26) is included with the FT5D and allows the transceiver to be attached and detached with a single touch while clipped to the belt.
This antenna can gets you on the air on 14MHz, and it has a useable frequency range. The VSWR is almost perfect at the centre-frequency abd the design uses no expensive components.
Experiments on HF antennas for restricted spaces. In this article author experiments antennas for 80-10 meters band having just a very small garden and several restrictions. Basic antennas consists of laded multiband dipoles and fan dipole antennas
Loading is a way to lower the resonant frequency of an antenna radiator. This technique is typically used in antennas that have radiating elements that are too short for the desired resonance frequency. In this excellent article the author experiment loaded vertical dipoles for 20 meters band
A searchable database of online websdr receivers, lists OpenWebRX, KiWi SDR and WebSDR from all over the world, providing a web interface to search and filter links to websdr
High quality microwaves components for professional and radioamateurs. Power Amplifiers, Low Noise Amplifiers, Es hail 2 Converter Transverter, Signal Sources, Passive Components and Accessoires
When operating contest in a multi transceiver environment interferences between the 40m and 20m are guaranteed. An easy and inexpensive way to reduce interferences is to add coax stub filters
In this article, author examine stresses placed on common-mode chokes (aka baluns) as hams use/abuse them, examine the efficiency of simple dipole multi- band antennas and their feed systems. Stressing a Balun.
This article demonstrate how to build and mount a 40 meter loaded dipole using basic materials. This antenna reduce the overall length of an HF dipole through the use of loading coils.
An interesting article on loading short vertical monopole antennas, representing six different methods. Base loading, Center Loading, Top Loading, Continuous loading, half and half loading and capacitive top loading.
In his page the author includes 27 mp3 audio files that compose the whole CW training course, instructions and whole lessons transcript are available in Italian and English.
The TangerineSDR is a Modular Software Defined Radio Project with the following objectives, Development of SDR radios that allow experimentation, provide support to unaffiliated other groups, to provide hardware modularity, to allow varying performance, To allow users to experiment with differing configurations.
DXFILE is an advanced log management program for radio amateurs. It allows complete management of amateur traffic and much more. Available only in French. Windows Shareware
Developed for beginners, hobbyists, and field engineers. Includes polar plots, rectangular plots for input impedance and VSWR, tabular data, NEC-Win Synth Light and Necvu 3D. Includes NEC2. The program also offers stepped-diameter corrections, Gain Averaging Test, CAD (.DXF) file input, 2-D and 3-D plots and antenna views, and graphical outputs. Run on older Windows version and is out of support.
This freeware application for Linux and windows, allows you to convert an ADIF file to a KML file so you can map your QSOs easily and open it with google maps, or google earth or any application supporting the KML format
Ham Cockpit is a program of a new type. All of its functions are implemented in the plugins, the main program simply loads the plugins and helps them work together. Ham Cockpit is an integrated environment for a Radio Amateur that every user can build according to his needs. It can work as SDR client, a logger, a cluster monitor, a propagation prediction tool, or have any combination of these working together.
The Home of BITX transceivers. Founded to encourage people all over the world to become more active in amateur radio, analog electronics and self-learning. Building and modifying radios is a great education.
This post describes how the newish Power Delivery (PD) mode mobile powerbanks can be used to power a SOTA transceiver as well as keeping your other hiking devices charged.
his controller uses the Yaesu GS-232 command set to control a Yaesu G-5500 Az-El rotor. The controller was designed to be compatible with the SatPC32 tracking program and should work with any tracking program that supports the Yaesu GS-232 format. This controller has been tested with the Arduino UNO and the Arduino Mega2560.
10 Elements Cross-Yagi Antenna for 433 MHz. The base of the 10el antenna is the recalculated RA6FOO antenna.Circular polarization is realized – by a phasing quarter-wave line, matching of horizontal and vertical polarization antennas
Data Decoder Utility is designed to enhance the operating experience for Flex Radio users by providing advanced connectivity to Peripheral equipment and radio control programs (RCPs) otherwise not available.
JOTA-JOTI is the largest Scouting event in the world with over 1.3 million Scouts participating across 150+ countries. Scouts and Guides across the world connect with each other during JOTA-JOTI using the airwaves and the internet.
JOTA is a spectacular opportunity to introduce Scouts to amateur radio. For many, this will be their first exposure to the world of ham radio. Some will go on to become hams, enjoying the hobby for a lifetime. A few will even find the basis of a career in science and technology.
The event has been held the third weekend of October since 1957.
The next Jota will be 15-17 October 2021
Why is there a JOTA-JOTI ?
Jamboree on the Air – Jamboree on the Internet (JOTA-JOTI) is a fun and exciting annual experience for all young people in Scouting using the widest range of technology communication channels to educate, promote cultural awareness, develop tolerance, as well as enhance sharing, collaboration and teamwork, along with building a sense of belonging to the worldwide Scout Movement. It is a “travel-free” Jamboree that takes place wherever you are in the world
JOTA-JOTI Purpose
Jamboree on the Air – Jamboree on the Internet (JOTA-JOTI) is a fun and exciting annual experience for all young people in Scouting using the widest range of technology communication channels to educate, promote cultural awareness, develop tolerance, as well as enhance sharing, collaboration and teamwork, along with building a sense of belonging to the worldwide Scout Movement. It is a “travel-free” Jamboree that takes place wherever you are in the world.
JOTA-JOTI Description
Jamboree on the Air – Jamboree on the Internet promotes a Scout’s sense of belonging to the worldwide Scout Movement and builds cultural awareness, develops tolerance, advocates sharing and collaboration as well as demonstrates teamwork.
It provides exciting opportunities for young people to explore technology and to develop technical skills including fostering innovation and creativity through communicating with other Scouts. A wide range of activities using communication technology are the chief methods of attaining these goals.
JOTA-JOTI strives for a meaningful engagement of as many young people from as many parts of the world as possible annually on the third weekend in October. This weekend is also an occasion to celebrate Scouting and to generate positive energy to support the development of the Scout Movement.
The event seeks to promote quality Scouting in a manner faithful to the purpose, principles and method of Scouting and consistent with the needs and aspirations of young people in today’s world.
The JOTA-JOTI programme shall be a reflection of the Promise, Law, Principles and Method of Scouting, as defined by the WOSM Constitution, and shall also reflect the most up-to-date policies and initiatives of WOSM relating to youth programme for all ages.
JOTA Operating Rules
All radio operators must operate their station strictly in accordance with FCC regulations.
Stations should try to contact each other by calling “CQ Jamboree” or “CQ JOTA” or by answering other stations sending this call.
Any authorized amateur radio frequency may be used. It is suggested that the frequencies listed below be used, at least for a starting point. Once contact is established, you can move to another frequency to leave the calling frequency open for others.
Any amateur mode of operation can be used such, as CW, SSB, PSK, SSTV, FM, and satellite. The more modes in operation, the more exciting the event will be for the Scouts.
JOTA is not a contest. The idea is to contact other Scout stations and allow as many Scouts as possible to talk to other Scouts and learn about who they are and what they are doing. You might think about counting the Scouts on both sides of the QSO rather than the number of QSOs!
JOTA Suggested Frequencies
All frequencies are shown as megahertz.
Primary HF recommendations are for General Class licensees. Technicians may take advantage of 10 m and VHF/UHF for voice communications.
After contact is made on Calling Channel or frequency, move to another channel or frequency for QSO.
Experiment with modes prior to JOTA or Radio Scouting demo. ‘Murphy’s Law’ prevails!
Use web search tools to find lots of helpful information about any of the modes commonly used for JOTA and Radio Scouting.
WOSM (World Organization of the Scouting Movement) calling frequencies are shown to indicate center of international activity.
World Wide JOTA HF Frequencies
Band
SSB (phone)
CW (Morse)
80 m
3.690 & 3.940 MHz
3.570 MHz
40 m
7.090 & 7.190 MHz
7.030 MHz
20 m
14.290 MHz
14.060 MHz
17 m
18.140 MHz
18.080 MHz
15 m
21.360 MHz
21.140 MHz
12 m
24.960 MHz
24.910 MHz
10 m
28.390 MHz
28.180 MHz
6 m
50.160 MHz
50.160 MHz
European JOTA Frequencies
JOTA isa worldwide event, and JOTA staions in Euripe are looking for contacts. To avoid a conflcit with the Worked All Germany contenst, European JOTA stations will be active on these band segments:
80 m
CW 3.560-3.800 kHz
SSB 3.650-3.700 kHz
40 m
CW 7.040-7.200 kHz
SSB 7.080-7.140 kHz
20 m
CW 14.060-14.350 kHz
SSB 14.100-14.125 kHZ and 14.280-14.350 kHZ
15 m
SSB 21.350-21.450 kHz
10 m
SSB 28.225-28.400 kHz
2 Meter FM Simplex
147.450, 147.480, 147.510, 147.540* * Use 147.540 as Calling Channel. Always listen first to avoid interfering with another QSO or auxiliary or control link. Avoid 146.520, the National FM Simplex Calling Frequency, as well as 146.550, which is commonly used by mobiles and RVers.
70 CM FM Simplex
446.000*, 445.950, 446.050, 446.100, 446.150 * Use 446.000 as Calling Channel. Always listen first to avoid interfering with another QSO or auxiliary or control link.
D-STAR
REF033A has been allocated as a full-time JOTA/Radio Scouting D-STAR Reflector. After contact is established, stations should disconnect from REF033A and connect to one or other repeater or migrate to an unused Reflector.
SIMPLEX Channels: 145.670*, 145.640, 145.610, 438.010. * 145.670 and 438.010 are commonly used as the National D-STAR Simplex Channels and should be used only as Calling Channels for JOTA. Always listen first to avoid interfering with another QSO.
DMR
All wide area talkgroups are permitted for use for JOTA for establishing contacts. After contact is established, stations should utilize as few resources as possible. For international, national, and regional QSO’s, stations should move their transmissions to one of the DMR-MARC UA talkgroups or to the DCI TAC-310 talkgroup.
For intrastate contacts, stations may use their area’s statewide talkgroup (if applicable). The use of your repeater’s local talkgroup (if applicable) is always permitted.
SIMPLEX Channels: 441.0000*, 446.5000, 446.0750, 433.4500, 145.7900*, 145.5100. All simplex frequencies operate on time-slot 1 and use color code 1. (*are commonly used as the National DMR Simplex Channels and should be used only as Calling Channels for JOTA. Always listen first to avoid interfering with another QSO.)
Need More Information?
Go to scouting.org/jota, for the information provided by the Boy Scouts of America.
This is a standard calculation method that can help you while tuning dipole antennas, by adjusting wire lengths. This method can be used also when you need to add lenght to your wires, and can be additionally used to quarter waves vertical antennas
The structure of this dual band VHF UHF antenna is very simple. It consists of two identical square loops, whose sides measure a quarter wave, connected together at the ends. A project by I5NZR
Experimentin wire antennas on top band using several type of aerials. This includes a 40 to 160 meters EndFed Half Wave kite antennas and 160m/80m loaded vertical antenna.
Operating the FT-817 from various types of batteries, such as Alkaline Cells, NiCd or NiMH rechargeable batteries. An useful article that compares usage of different types of batteries for the Yaesu FT-817
This is a Bourne Shell script that will automagically download the FCC Amateur Radio license database, parse it, and populate a MySQL database. The database can be searched using the command line and is very fast.
One of the interesting features of the FT-817 is that many of the conventional calibration settings that would have, in the past, been done using manual adjustments of coils, capacitors, and potentiometers, are done via software.
The DXZone is the largest human created and maintained library of web sites dedicated to Amateur Radio, currently lists 20.000+ links organized into 600+ categories and subcategories. Ham Radio operators review new sites every day since 1998, for potential inclusion in the Directory, and to evaluate the best place to list them
December 12th, 1901 is certainly a date with a historical relevance in radio transmissions.
In fact, at 04.30 GMT of that day, Guglielmo Marconi succeeds in sending the first transatlantic wireless communication.
Succeeding in this contact, Marconi demonstrate that radio waves transmissions could be transmitted even across the Atlantic ocean.
With this success Marconi, in addition, disproved detractors who told him, that the curvature of the earth would limit transmission to 200 miles or less.
The station in Cornwall, England instead was composed by a twenty-four ships’ masts each 200 feet high, and the transmitter was powered by a 32 brake horsepower engine driving a 25 kilowatt alternator.
History says that detractors were correct when they declared that radio waves would not follow the curvature of the earth.
In fact today we know that radio waves had been headed into space from England when they were reflected off the ionosphere and finally bounced back down toward Canada.
Science demonstrated and explained this contact, made thanks to Radio wave propagation, just a few years later.
Therefore thinking in terms of amateur radio logic, we should consider this experiment as the first DX contact ever.
If you are interested in Marconi’s experiments and history, probably you can find interesting arguments and further details about this story here:
