Recording type direction finder

The authors formerly made a report on a direct vision type direction finder for high frequency, which has high sensitivity and by which multiple signals or scattering signals can also be measured. Since then, the finder has been used for studying characteristics of the ionospheric propagation waves. In order to make continuous measurement of bearing convenient, a recording apparatus adaptable to the present direction finder has recently been developed. The diagram of the whole system of the direction finder is shown. The left part of the figure shows a diagram of the former finder and the right part surrounded by dash lines is the recording part. The finder adopts the so-called one-receiver system in which a receiver REC amplifies four kinds of voltages of different directivities in succession as time-division signals by using electric switching. Aside from the general explanation of the finder, the working principle of the recording part is briefly described.