Normal Reception
Local Television Channel Three Interference
These pictures show various stages of interference as seen on my local TV monitor. The TV sits across the room and operates with a pair of rabbits ears. The picture quality varies enormously from one time to another, moving the portable antenna restores the picture. This cannot be explained unless certain power levels produce reflections that are stronger at times than the direct signal. To some extent this is covered in another chapter and responsible for a special mode of reception
Interference Pattern
Horizontal bars can be seen appearing across the screen and are constant irrespective of my transmitting frequency within the 20 meters band. This can be misleading as newer generation TV sets have lots of time to stabile the horizontal and vertical time framing signals. The interference therefore appears locked to the vertical sync pulse at the start of each frame. With further interferences the sync still locks, but start to blot out the video composite signal, as seen in the picture.
