Wednesday, May 1, 2013

First two-way shortwave contact with England from Melbourne!

It is not commonly known, but it is claimed that the first two-way amateur shortwave radio contact between Australia and England was on November 14, 1924. This was from "3BQ", operated by Max Howden, at his residence here in Mont Albert, at 18 Blackburn St, just a few streets away from my home! This story appeared in the Box Hill "Reporter" newspaper of November 21 1924. The achievement was also reported in the Melbourne "Argus", November 26, 1924, and the longish article can be viewed or downloaded from the National Library of Australia archives,
The house is long gone, and three Units now occupy the site.
This is the actual article, with the original text "cleaned up" by myself, but grammar has not been changed!
The year of 1924 was marked by innumerable experimental SW two-way long-distance transmissions from amateurs in Australia.
Amateur's Apparatus Described.
Melbourne Argus - November 26 1924
A description of the transmitting and receiving apparatus used at his experimental wireless station at Box Hill during  recent wireless tests to England was given by Mr T W M Howden at a meeting of the Wireless Institute at Anzac House ion Melbourne last night.  At the dinner, which will now in future precede all general meetings of the Institute, Mr Howden was presented with a pair of wireless headphones in recognition of his performance.
Mr Howden said that a feature of the apparatus used in the communication with England was that, compared to the appliances generally used for long-distance wireless transmission, it was extremely simple, and the receiving apparatus was of an inexpensive nature The power used at the transmitter varied between 100 and 150 watts and the current in the aerial from 0.9 of an amp to 1.4 amperes A single valve, having a rated input of 250 watts, was used in the transmitter and this was operated with a pressure of about 2000 volts.
Power to work the station was obtained from the electric light mains, and the pressure was raised to about 2000 volts by a suitable  transformer The alternating current delivered by the transformer was converted into a direct current by being passed through a chemical rectifying device consisting of 101 jars A standard type of amateur transmitter, which had previously been used for low power transmission, was employed.

The aerial used was about 75ft high, and consisted of a small flat top ' T * aerial operated in conjunction with the ' T" type counterpoise which was used instead of an earth connection.
To obtain satisfactory operation on the short wave lengths used it was necessary to make the aerial as small as was consistent with the maximum possible height and the counterpoise was also made as small as would give satisfactory tuning in conjunction with the aerial.
In this manner no trouble had been experienced in maintaining a steady wave of 88 metres.
The receiver used was in principle one of the first and most generally used types of valve circuits. Only two valves were used, and the receiver contained no radio frequency amplifier.
In designing the tuners for the receiver, special precautions were taken to prevent any loss of the received energy, and in this manner it had been possible to receive American amateurs with the aerial disconnected from the receiving apparatus.
This is the location, indicated by the Red Icon (Google Maps)

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