Hostname: page-component-cd9895bd7-lnqnp Total loading time: 0 Render date: 2024-12-24T00:58:20.192Z Has data issue: false hasContentIssue false

An apparatus for recording the strength of wireless signals from a Morse sender

Published online by Cambridge University Press:  24 October 2008

K. G. Budden
Affiliation:
St John's College

Extract

In many radio investigations of the ionosphere it is desirable to use senders working on different wave-lengths and situated in different positions with respect to the receiver. For this purpose it is very convenient to make use of commercial senders which work more or less continuously at high power. It so happens, however, that these senders usually emit Morse signals consisting of dots and dashes of variable lengths and with variable intervals between them, so that an instrument which records the mean signal will give an indication which depends on the speed of sending and on the spacing and length of the signs. In order to obtain a reading which depends only on the signal amplitude, it is possible to employ a quick moving recorder such as a string galvanometer or a cathode ray oscillograph, which will follow the individual Morse signs. With both these types of recorder the record must be made photographically so that changes in the signal strength are not noticed until the record is developed. This is a serious disadvantage in investigations of short-lived disturbances of the “catastrophic” type.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 1938

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

* The instrument used was made by the Cambridge Instrument Company.

* Dellinger, , Bur. Stds. J. Research, 19 (1937), 111.CrossRefGoogle Scholar

Budden, and Ratcliffe, , Nature, 140 (1937), 1060.CrossRefGoogle Scholar