The Exelrad Noiseless Antenna

The Exelrad Noiseless Antenna

Exelrad Noiseless Aerial (1937)

Historical advertisement from the 1930s.

Practical Details of … “Eliminoise” Aerial Equipment


Historical article:

Typical Sales Advertisement from

The N.Z. Radio Times

February 2, 1937

It is generally agreed that if a receiver has to be operated where interference is directly radiated, the most effective way of improving reception is to attend to the aerial; the active span should be erected as far from any metallic conductor as possible, and the down lead which is incapable of picking up any radio voltages be used for connecting the aerial to the receiver.

Clandestine Radio In The 1970s


Martin Hadlow

While accessing some declassified US Government documents in the archives, I came across an interesting report from March, 1971. Headed Soviet and East European Clandestine Broadcasting, the report noted that “The USSR and East European Communist countries today are engaged in extensive clandestine broadcasting operations to supplement the efforts of their official acknowledged international broadcasting networks”.

The report listed nine stations, which broadcast a total of 232.25 hours a week. No doubt many of the stations are familiar to long-time DXers. Personally, I never heard any of the nine listed by the US authorities in their classified report. However, reading the list, and the raison d’etre of each station, is like stepping back in time to an era when the Cold War was at its height.

High Efficiency Aerial For Shortwaves – Historical




HERE is a short wave antenna that has helped me very much in my SWL work. I believe it is an original idea, for I have never seen or heard of one like it. It occurred to me when I was trying to figure out a way to have good directional antenna (all directions) without having to have a separate antenna for each direction. It has worked wonderfully well for the past six months, so I thought that others interested in the same field might like to try it.

Radio Canada International SW Towers


RCI Sackville (Tantramarsh)

Thanks to Paul Rawdon reporting in DX Dialog “This could be well worth seeing.An experimental documentary film about the RCI shortwave radio towers.  Images captured on 35mm film, and stories told in English, French, and Mi’kmaq.

Wave Traps – Historical Article






R. J. A. LITTLE, A.M.I.R.E. South Melbourne

From – The Australasian Radio Times – July 1947

A WAVE TRAP can be defined as a circuit containing at least one condenser and one coil wired in series or parallel to form a tuned circuit. A most common form of wave trap is one utilising a parallel tuned circuit.

Modified Views On Shortwave Propagation


Historical article from May 1943 Australasian Radio World

TWO abstracts from technical papers of German origin which have recently appeared in “Wireless Engineer” deal with matters of particular interest to those engaged in short-wave work.

The first of these is from a paper by B. Beckmann, W. Menzel and F. Vilbig, and gives details of a particular form of “scattering” in the ionosphere, which results in strong signals being obtained within the skip distance of a transmitter.

Great Circle Gadget

Radio World

Historical Article: Tells You Where To Point Your Directional Aerial

The Atmosphere’s Electrical Fringe

Radio Review

Historical Article: How the Ionosphere Affects Radio Transmission

From the Radio Review of Australia (June 1938)

EVERY reader of this journal must have encountered at least one reference to the vagaries of the ionosphere” in the course of his reading, and he is also bound to have come across references to ‘sun-spots” and their effect on terrestrial conditions. It is quite possible that these references, usually of the incomplete newspaper” variety, have left him wondering what it is all about. The following article, which is by a scientist of the Carnegie Institution, Washington, U.S.A., sums up present knowledge of the ionosphere, sun-spots, and their relation to radio transmission, very neatly and will give the reader a much more intelligent appreciation of what is happening next time he hears of a ‘solar hydrogen eruption” or a “sun-spot cycle.

Radio Australia To Slash SW Services

raThanks to Dallas MacKenzie reporting on the DX Dialog reflector for the following:  “RA news announced that 60% of its services to close (23/7 News)”    This includes the Pacific Island Service which will only Broadcast News, and local ABC programmes…(Similar to RNZI). Further Info will be available from their web page shortly”

Gary DeBock & The Ferrite Sleeve Loop

FSL15+in+US+De+BockThanks to Tony King reporting on the DX Dialog reflector, here is a photo of Gary DeBock with his invention, the Ferrite Sleeve Loop. “Gary DeBock’s latest creation with which he is scoring many NZ stations on his Tecsun PL380. Probably about 200 ferrite rods on this “sausage roll” .pic attached.  He’s in the right uniform, and his PL380 lives in an NZ emblazoned mobile phone pouch I sent him last year.” Rumour has it one or two Kiwis are building them!

And also from Gary is a Youtube video of his antenna picking up trans-Pacific DX from New Zealand.

Aussie MW Band In 1937

Australian Broadcast Stations 1937

Click on the image to enlarge.

Solving Noise Problems In The Modern Home

toroidsJim Brown K9YC is the author of an excellent guide to solving RFI issues around the radio shack. His very useful article “A Ham’s Guide to RFI, Ferrites, Baluns, and Audio Interfacing” has much information useful to SWLs looking for a way to reduce noise and there are a lot of instances where the noise-source is in the home.  You’ll find a lot of interesting material on Jim’s website.


Solomon Islands Back On Shortwave

SIBC logo

Reporting on the DX Dialog user-group, Bryan Clark has this hot-off-the-press item:

After a couple of months absence from it’s daytime channel – 9545 kHz,
SIBC conducted tone tests yesterday and today is back with full audio -
excellent signals noted here at 0345 UTC during a music dedication

Soviet Jammers From Latvia

jammertxNot all of the Soviet jamming originated from Russia, their replublics also hosted jammers, and what’s more some were made in the USA. The Latvian History blog carries this interesting story. They also make the comment that the jammers blocked transmissions from Soviet-friendly states as well. From the same site, there are interesting blogs on Nazi radio propaganda during WW2 and Latvian-made valve radios.

Stop That Noise!

Historical article from Lamphouse Annual 1947-48


Lamphouse Annual 1947-48 CoverSTOP THAT NOISE!

MANY excellent programmes are ruined by man-made interference. In order to locate the source of interference you should endeavour to obtain some clue to possible causes, and, by the process of elimination, determine the electrical system in which the trouble originates.

The local Radio Inspector of the Post and Telegraph Department is always willing to investigate complaints of continued interference, but before calling on his assistance you should endeavour to eliminate the possibility of the trouble being in your own receiving set, your aerial and earth system, or caused by some electrical appliance or circuit in your own home.

Remember The Cold War Jammers?

jammersThese QRM-generators were used mostly by Eastern Bloc countries to jam shortwave transmissions from the West. They used all manner of continuous tones and raucous audio, anything to make the desired signal unintelligible.

The Radio Jamming website has some excellent material backgrounding their existence along with sound clips so you can hear just how pervasive their cacophony was. The website is the work of Rimantas Pleikys, not only a shortwave listener but also the former minister of communications and informatics and  past member of the Lithuanian parliament!

Thanks to Paul Rawdon for letting us know that the DVD Empire of Noise mentioned on the home page is on YouTube

Convention 1976

tatumparkThanks to Dawn Chambers, there are some excellent photos online taken at the NZRDXL’s 1976 Convention, held at Tatum Park near Otaki.

SW Radio Africa To Leave SW


Thanks to Alokesh Gupta in India, Clandestine broadcaster SW Radio Africa is leaving shortwave on July 18th and shifting its radio channel to a satellite service and other unmentioned media. More on their website.

Even More On Those Numbers Stations


There is a continuing fascination among radio listeners about “numbers stations”. The “War Is Boring” blog carries an article on two in particular, “The Buzzer” and “Yosemite Sam”, who join the pantheon of mysterious broadcasters alongside “The Lincolnshire Poacher” and “Cherry Ripe”.