[Ola Hernvall]

What bandwidth is required for transmission with A1D modulation? For your information, the bandwidth of SAQ is 100 Hz.

Best regards,

Ola Hernvall
AlexanderSAQ

[Ola Hernvall]

We agree with the opinion that the SAQ antenna is oriented for best radiation towards New York. Though, we have not seen any document that confirms this.

Anyhow, the radiation pattern of the antenna is almost omnidirectional, with a slight increase in NW-SE direction and a dip in the NE direction.

Radiation-SAQ

[Ola Hernvall]

SAQ has no facility to measure the output power. The only instrument connected to output is a thermocouple that measures the current from the alterator to the antenna. However, we estimate that the power to the antenna is about 70 – 80 kW and the effectively radiated power from the antenna is about 8 kW.

[Ola Hernvall]

I think there are two main reasons for the problems of receiving SAQ in North America today.
The first reason is the receiving antennas used. As radio amateurs today can use antennas not bigger than their own garden, the antennas for receiving commercial telegram traffic were huge. The commonly used antenna was the Beverage antenna. The antenna in Riverhead on Long Island outside New York for receiving European transmitters was about 14 000 meters. It also had a facility to cancel local noise from nearby transmitters, thunderstorms and statics. More information on the Beverage antenna can be found here: http://www.nrcdxas.org/articles/WaveAntenna.pdf
The second reason is that the amount of man-made noise has increased over the years. Power lines, railways, washing machines, dimmers, all contribute to an increased noise level. At least in Europe, it seems that local noise is a worse problem than low field strength when receiving SAQ.

[Ola Hernvall]

All radio telegrams were handled at the Radio Central in Gothenburg. The messages were punched on paper tapes. These were inserted in a machine called transmitter, that transferred the information on the paper tapes into morse code. This was sent from Gothenburg on a telegraph line along the railway, first to Varberg and then to Grimeton railway station, and after that over the fields to the radio station, where it actuated the first telegraph relay of SAQ.

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