LINKS
Links to items of interest. Please submit new ones via the form or to info (at) ontheradio.org
DMR (Digital Mobile Radio)
This includes D-Star and Yaesu System Fusion, which can be reviewed separately here
A good overview of DMR can be found here.
There are a number of competing networks in the UK. One consequence of this is that the old DV4 Mini dongle will no longer work with DMR (although still works with D-Star and YSF). A MMDVM hotspot is an easy way of getting onto DMR if you are not close to one of the repeaters.
Es'hail-2
Oscar 100 is 2 amateur radio transponders hosted on the Es’hail-2 Direct Broadcast TV satellite owned by Es’hailSat in Qatar and is the first ever amateur payload on a commercial geostationary satellite.
Information on using amateur TV with Oscar 100 is here at the British Amateur Television site. Other general information is on the Amsat site.
Web SDR (Software Defined Receiver)
A WebSDR is a receiver connected to the internet, allowing many listeners to listen and tune it simultaneously. SDR technology makes it possible that all listeners tune independently, and listen to different signals.
A comprehensive worldwide list is here. One popular SDR for 4m is at http://www.barionics.co.uk in Clanfield, north of Portsmouth, Hampshire.
Radio Transmitter Coverage Tool
Register for free and plot your coverage for VHF and UHF. The radio coverage tool is intended to aid broadcasters (but works for amateurs!) in analysing the approximate coverage with various transmitter sites, power levels, antenna heights and antenna gain. The coverage tool is based on the Longley Rice modelling techniques, and publicly available SRTM terrain data.
Low-cost Amateur Television
Low-cost ATV, using readily available modules that will transmit and receive within the amateur band. The ATV column of the September 2017 edition of RadCom had an article on 5.6GHz ATV, using cheap 'First Person Video' (FPV) transmitter and receiver units (intended for use in drones), - for under £30.00. Details on M0PKW's site.
Surface Elevation Tools
Surface Elevation Tools can be used to analyse the surface elevation profile from one point to another to determine line-of-sight, and to work out the feasibility of a wireless link.
Solwise - UK-based.
Scadacore - Takes into account curvature of the earth and antenna height. Usage tip - starts in the US. Drag the two points to the UK and then zoom in to place at the precise map locations.
Onthegomap - Instructions a bit lacking, but for radio use click in the diagonal line in the box at the top centre. Position the mouse cursor at the start point, right click. Position the mouse at the end point, right click. Click on the mountain symbol, bottom left, to show terrain. Click on the "X" top left to clear path and start again.
Not surface elevation, but the Ordinance Survey mapping is available for free, if you need to view a good map.
Also, not surface elevation, but a quick way of determining line of sight distance, at https://www.distance.to
Amateur Radio Database
QRZ - Look up a callsign, create your own logbook, amateur radio news, and more.
Hamcall - Look up a callsign and many other links.
In the UK, QRZ is the most widely used. It helps, especially on 4m and above to have your approximate (or exact, if you don't mind) location on the map. This can help with pointing a directional antenna such as a Yagi.
High Spots for Portable Ops
High spots across the whole of the UK. Find a local high spot for your portable operation.
Repairing an Icom IC-7300
An article by Chris, G3WIE, on repairing an Icom IC-7300.
Some notes on a repair to an Icom IC-7300 belonging to a member of his local club. During a storm, the house developed a leak, and water got into the radio. It was cleaned up with alcohol which is the best thing to do in the circumstances. The radio didn't work...
The radio was sent to a UK distributor, who declared that it couldn't be repaired economically. Chris took that sort of statement as something of a challenge - a 7300 is far too nice to be thrown away. This is the story ...
The radio was sent to a UK distributor, who declared that it couldn't be repaired economically. Chris took that sort of statement as something of a challenge - a 7300 is far too nice to be thrown away. This is the story ...
PDF Document (2Mb download)
Please note that this document is watermarked. Please contact the author (G3WIE), via QRZ, if you wish to re-distribute.
Miscellaneous Software
Zelscope is a Windows software that converts your PC into a dual-trace storage oscilloscope and spectrum analyser. It uses your computer's sound card as analog-to-digital converter, presenting a real-time waveform or spectrum of the signal - which can be music, speech, or output from an electronic circuit. Zelscope features the interface of a traditional oscilloscope, with conventional gain, offset, timebase, and trigger controls. As a real-time spectrum analyzer, Zelscope can display the amplitude and phase components of the spectrum.
HamScope is a multi-mode communications interface for amateur radio that supports:
- PSK31
- RTTY
- ASCII
- MFSK16
- PACKET
- CW
DMR Guide
DMR (Digital Mobile Radio) uses the Motorola TRBO protocol for communications. As with other other digital modes such as D-Star and C4FM, the TRBO protocol converts your voice into a digital form and sends it out via RF. This allows you to communicate to other DMR radios and also DMR repeaters, which are networked together via the internet.
A full guide to DMR (Digital Mobile Radio) is available here.
Every user on the DMR network is required to obtain a (free) unique ID that is put into your radio code plug. Please click here.
QRM / Interference
Many of us experience high levels of noise on the HF bands. These two sites offer a lot of help and suggestions in tracking down the source and applying fixes, where feasible.
Advice on power line devices.
Advice on common electronic devices around the house. such as lighting, switched mode power supplies, VDSL internet, etc.
Advice on setting up SDR dongles and Windows 10 drivers
This can be very problematic with Windows 10 as it can overwrite the correct driver.
Circuit Design
The largest online community of engineers in the world. Lots of advice, circuits, etc.
The IFA2 Interconnector, Lee on the Solent
There is a lot of concern about possible interference from large power inverter installed at Lee on the Solent, where an undersea cable from France is terminated.
This site contains all the details.
HF, 50/70 MHz, 144/432 MHz, EME and microwave chats
Many chats linked to DX clusters. Free to register and use. Started out as a 6m specialist site, but now covers much more.
Accurate Time
Most of us know what day it is, and the date. However, accurate time is not always available. This site provides an easy solution.
Other Links
You may be interested in some of the links in the Radio Presenter part of the site. These include getting a free local landline number, finding fake reviews on Amazon, checking computer files for virus, checking authenticiy of web site, and an uncensored list of broadcast stations streaming on the internet.