Manfred von Ardenne, a German television engineer, began experimenting with CRT receivers in 1930. Using mechanical scanners, he produced good quality images using CRTs.

 

Here is an early image, from December, 1930

By April 1931, the picture quality was much improved

 

In April of 1931 von Ardenne had made a flying spot film scanner. It produced a 60 line picture, using a horizontal scan rate of 1500 Hz. and a vertical scan rate of 25 Hz. An 8000 volt power supply was used on the CRT.

 

The scanner, with the CRT and raster visible

A closeup of the film mechanism

 

The neck of the CRT, showing the deflection plates

A picture from the screen

 

 

A block diagram. Notice that the scanner is connected directly to the monitor CRT. The signal was not broadcast.

 

 

Here is a block diagram of a scanner with sync pulses added to the video, for possible broadcast.