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Extreme interference at the upper edge of the 150-200 metre band - the official
wavelengths allocated to amateurs by the Second National Radio Conference in 1923

free-for-all, followed by a period reserved - forced amateurs to shift to shorter and shorter wavelengths; however, amateurs were
for the selected 20 CW and seven spark limited by regulation to wavelengths longer than 150 metres (2 MHz). A few fortunate
qualifying stations. More than 12 British amateurs who obtained special permission for experimental communications below 150
companies offered prizes, including three metres completed hundreds of long distance, two-way contacts on 100 metres (3 MHz) in
Burndept receivers, a Sullivan laboratory 1923 including the first transatlantic two way contacts in November 1923, on 110 metres
wavemeter worth £35 and three cash prizes (2.72 MHz).
from the Marconi Scientific Instrument Co. By 1924 many additional, specially licensed amateurs were routinely making trans-
In May 1921, the British suggested oceanic contacts at distances of 9600 km and more. On September 21, several amateurs
that “if a good US amateur with an in California completed two-way contacts with an amateur in New Zealand. On October
Armstrong Super receiver could be sent 19, amateurs in New Zealand and England completed a 90-minute two-way contact nearly
to England, reception of US amateurs halfway around the world.
would straightway become commonplace.” On October 10, the Third National Radio Conference made three shortwave bands
Therefore, at the first ARRL convention available to U.S. amateurs at 80 metres (3.75 MHz), 40 metres (7 MHz) and 20 metres
in Chicago in September, the board of (14 MHz). These were allocated worldwide, while the 10-metre band (28 MHz) was created
directors unanimously voted the funds by the Washington International Radiotelegraph Conference on 25 November 1927.
to send a US amateur to Britain for the
tests. Thus began one of the strangest output circuits tuned to the intermediate
DXpeditions in amateur radio history. frequency of 100kHz. For CW reception,
a harmonic signal from a separate beat
Paul Godley made it happen frequency oscillator was loosely coupled to
The ARRL extended an invitation to Paul the detector feeding the final audio output
Godley to undertake the test and to travel amplifier. There were individual filament
to Britain. Godley is the first person who rheostats for all ten valves.
adapted the Armstrong generative circuits Godley sailed on the Aquitania on 15
for shortwave work. He originated the November 2021. Special arrangements had
variometer regenerators which became already been made with the UK authorities
very popular amongst the amateur to bring his apparatus to England and erect
fraternity experimenting with shortwaves. antennae.
Before the final tests planned for 10 In one of those historical coincidences,
and 11 December 1921, there was much during his voyage to England, Godley met
discussion to ensure that the test results, Harold Beverage, who convinced him to use Typical variometer popular in the 1920’s
if any, would be credible. It was decided to a specially designed, highly sensitive, and
divide part of each test night into free-for- directional 1,300-foot antenna, referred to near London but the RF noise level was
all periods and individual test periods for as the Beverage antenna. so incredibly high that Goldley decided
the official test stations. A Beverage antenna consists of to move his testing station to Ardrossan,
While all the secrecy and scheduling a horizontal wire from one-half to west of Glasgow in Scotland. As time was
arrangement were carrying on, Godley several wavelengths long (tens to hundreds running out, the setup had to be housed in
was busy building special amplifiers, of metres at HF to several kilometres a tent on an open field where the antenna
testing various tuning arrangements and for longwave) suspended above the could be erected.
experimenting with different antennas. ground, with the feedline to the receiver Plans were put in place to send daily
The equipment he chose to take to attached to one end, and the other end messages from Radio MUU addressed to
Britain included a Paragon regenerative of the Beverage terminated through a the ARRL at Hartford. So great was the
set, a tuner, and a nine-valve superhet with resistor to ground. The advantages of the interest of commercial companies that
a regenerative radio frequency amplifier Beverage are excellent directivity and a Marconi officials arranged to send these
stage and local oscillator, followed by five wider bandwidth than resonant antennas. reports at a specific daily time and by
RC-coupled amplifier stages with input and Initial plans were to carry out the test hand keying, so that the amateur radio
community could copy it directly and get
first hand word from Godley.
Over the course of the test period,
more than two dozen stations were heard
between 230 and 235 meters, roughly 1
3 MHz in what is now the AM broadcast
band. Some utilised spark-gap transmitters,
others employed vacuum-tube CW
Circuit diagram of Paul Godley Superheterodyne receiver transmitters. n

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