Tag «Signal Processing»

Logarithmic Amplifier Using MC1556 Op-Amp

The circuit below is a logarithmic amplifier using an MC1556 op amp. The 10K pot is an offset adjustment.  Here is  a schematic diagram of one classic example of  general purpose  logarithmic converter circuit employing LM1556 op-amp: The popularity of logarithmic amplifier is decreasing as the microprocessor and microcontroller chips are  getting lower and lower …

AGC (Compressor) Speech Processor

This is a speech processor circuit that can be used in communication radio circuit. This circuit consist of two sections, they are amplification and compression or dipping. The combination of these processing will improve the  SSB communication intelligibility and provide higher average level while avoiding clipping. The 100K pot is used to adjust the compression …

Infinite Resolution Frequency Multiplier/Divider

Normally, frequency multiplier or divider has only discrete ratio operation since it uses digital divider as the main process for division or multiplication. By first converting the incoming frequency into a proportional DC voltage, we can perform frequency scaling easily with no restriction of discrete ratio operation. Here is the block diagram the scheme: We …

Mic/Guitar Compressor with Transitor Bias Control

This is a compressor circuit that can be used for dynamic mic, condenser mic, or electric guitar pickup. This circuit doesn’t produce very good sound output, but it has very stable amplitude/volume. This compressor circuit design is unique since it uses base current control for manipulating the gain. Here is the schematic diagram of the …

Frequency/Tone Decoder with TC9400 FVC

Another application of FVC (frequency-to-voltage converter) is tone/frequency decoder. This circuit is used to determine the frequency band of an oscillation signal. This circuit is used in many application like determines the frequency band in the signal and remote control where the frequency band corresponds to a different command. This circuit uses TC9400 F/V converter …