AP 3302 Pt. 3
Section 2
CHAPTER 5
Clamping Circuits
This difficulty is overcome by positively clamping the minimum signal voltage to a fixed value (set by the brightness control) as shown in Fig 14b. In addition a positive limiter is included in the circuit. This ensures that all signals produce the same brightness of echo whatever their strength. If signals were not limited in this way the weak echoes would be masked by the stronger ones.
