| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a PPI(plan position indicator), which arbitrarily sets the azimuth of a scanning lien displayed on a CRT. SOLUTION: An azimuth angle signal-generating circuit 1 generates the azimuth angle signal in correspondence with an arbitrary azimuth setting and outputs the signal to an azimuth angle signal-switching circuit 2. The azimuth angle signal-switching circuit 2 selects the azimuth signal from the azimuth angle signal of the X axis and the Y axis supplied from the outside of the azimuth angle signal from the azimuth angle signal-generating circuit 1 and output the signal to X axis sweep and Y axis sweep-generating circuits 3 and 4. The X axis sweep and Y axis sweep-generating circuits 3 and 4 generate the sweeping wave forms in correspondence with the azimuth angle signals and output the wave forms into X axis and Y axis deflecting and amplifying circuits 5 and 6. The X axis and Y axis deflecting and amplifying circuits 5 and 6 convert the sweeping wave forms into the current wave forms, amplify the wave forms and output the wave forms into a deflection coil 8. The deflection coil 8 deflects the electron beam of a CRT 7 and displays the beam on the CRT 7.</p> |
