GW4ALG's 136 kHz Pages

[ GW4ALG went QRT in February 2007 ]

Home ]

Up ] Antennas ] Equipment ] For Sale ] Links ] Logbook ] [ Introduction ] Station Summary ]


View/Hide Contents Window

A picture of the author

Welcome to the world of 136 kHz! 

My name is Steve Rawlings, holder of the amateur radio callsign 'GW4ALG'.  

Through this site, you can find out how to make the most of this amateur radio allocation.

GW4ALG Goes QRT On 136

Steve GW4ALG was active on the 136 kHz band from March 1998 through to October 2001.  For Steve, the arrival of the first RSGB 136 kHz repeater on 10th October 2001, located in southern England, took away the main attraction of the band.

Naturally, the repeater brought with it the usual bunch of pirates, and lid operators - and even a certain amount of 'cheating' by those claiming to have 'worked' DX on the band.

Click here for more information.

Note: This web-site is no longer being maintained.

 

The 136 kHz band
The 136 kHz band was made available to UK amateurs on 30 January 1998 and covers just 2100 Hz (2.1 kHz), from 135.7 - 137.8 kHz (about 2,200 metres).  The power limit in the UK is 1 watt effective radiated power (ERP).

136 kHz is well-suited to radio experimenters with an interest in antennas and the home construction of transmitting and receiving equipment.  The most common modes in use are normal CW using conventional morse code (frequently within the range 8 to 15 words per minute), and very slow CW (known as QRSS). 

Even if you don't have much space for erecting antennas, you will be surprised what can be achieved by putting up antennas similar in size to those used for the short wave bands.  Experimentation on this band can be enjoyed by both short wave listeners (SWLs) and by those licensed to transmit on the new band. 

The best time to listen for stations on 136 kHz is on Saturday and Sunday mornings, when activity is highest.  Start by listening in the CW segment, 136.0 - 137.4 kHz.  You may also hear very slow morse transmissions (QRSS) in the range 137.6 - 137.8.  However, with a morse 'dot' duration of around 3 to 30 seconds, QRSS is hard to decode by ear!  In practice, QRSS is decoded on a PC using software that displays the marks and spaces of the morse characters on the computer screen. Thus QRSS signals are often said to be 'seen', rather than 'heard'!  The very long dot length allows signals to be detected (seen) at signal levels some 15 dB below the noise level.  

My location
I am in an elevated part of Chepstow, south east Wales; about 70 m above sea level (ASL) with a good 'take-off' to the south and the east.

Location map for Chepstow

For a detailed street map of my location, click here

For an OS map (1:50,000) of my location, click here

How I got interested
It was Dave, G3YMC, who got me interested in the low frequency (LF) bands.  By the time the 136 kHz band became available, Dave had already been experimenting with receive converters for 73 kHz.  Dave showed me how easy it was to build an LF converter for use with a 10 MHz receiver and was in the process of modifying his converter for 136 kHz.  I was soon hooked.  (After 6 years of doing an Open University degree course, I was itching to get back into some home-construction projects!)

The new 136 kHz band presented an opportunity to build an amateur radio station for a band where there was very little commercial equipment available.  When I started constructing my LF station in February 1998, I had no TX; RX; or RF test/measuring equipment for the LF part of the radio spectrum - so there was much to be done!   First out of my workshop came an LF dip oscillator; LF SWR bridge; transverter; 100 W PA (later followed by a 400 W PA); and, of course, the antennas.

The Shack
This picture shows Wil operating as MW/PA0BWL from the GW4ALG shack.  The picture, taken in October 2000, shows Wil  working Werner ON6ND.  The QSO was made on CW using 400 watts to my 12 m experimental vertical.

Wil, MW/PA0BWL

 

Exciting times for amateur experimenters
My initial tests were carried out using an old Yaesu FT707 transceiver (operating at 10 MHz) with my homemade transverter (136 kHz transmit/receive converter).  Just 15 watts RF output from the transverter into a tuned loop antenna was enough to get an S5 report from Brian GW0GHF over a distance of 42 km.  On receive, I was delighted and amazed to hear a number of stations such as G2AJV; G3XTZ; and G3LDO - all greater than 150 km away!  136 kHz was indeed looking like a band with some potential!

One of my most memorable contacts on 136 kHz was with Graham G3XTZ.   Graham was one of the first stations to report hearing my transmitter test signals.  Then, on 21st March 1998, we made the first England to Wales 2-way contact over a distance of 157 km - an amazing distance for such little power; probably just a few milliwatts ERP.    Later, my contact with OH1TN in November 1998 established, at the time, a new world distance record on 136 kHz (1915 km) and remained the UK distance record for over 12 months.

You can do it too!  Start constructing your LF station today!
Since those early days on 136 kHz, the sharing of ideas and test results has enabled a small, but growing number of LF enthusiasts to generate greater power levels on transmit; improve the reception of weak signals; and increase the efficiency of their antennas.  

Within these pages, you can discover how, from a small back garden in Chepstow, I made record-breaking contacts with over 14 countries - and how I made contacts with other LF stations over distances that I thought would be 'impossible' when I made my first tentative test transmissions on 136 kHz back in March 1998.

Further information
General information and references relating to 136 kHz can be found via the hyperlinks at the bottom of this page.  Information about the transmitting and receiving equipment at GW4ALG can be found via the hyperlinks at the top of this page.

Good luck on 136 kHz!

Steve Rawlings, GW4ALG
03 October 2001


Bracknell Amateur Radio Club

Dave Sugden (G4CGS) Memorial Trophy

Pictured here is the Dave Sugden (G4CGS) Memorial Trophy which is awarded annually by the committee of the Bracknell Amateur Radio Club "to recognise exceptional contributions to Amateur Radio and the Club". 

I am pleased to have been awarded the Trophy in 1999 for my efforts on 136 kHz.

(Note that the callsign G4CGS has since been re-issued to Dave's son, Steve Sugden.)

Located in Berkshire, England, the Bracknell Club has been very keen to support members engaged in experiments on the new LF bands, and new members are always welcome.  Other members active on LF are G3TLH and G3YMC.  Further details about the Bracknell Club can be obtained by clicking here.

 


Articles ] Definitions ] Farewell ] News Reports ] Publications ]