Based on an LM36000 OTA this circuit was found in the July 1988 issue of Radio Electronics magazine. It covers frequencies in the range of 45 Hz to 45 kHz.
This digitally programmed gain amplifier was obtained from Signetics documentation from the 1980s....
This circuit is from a 60's documentation. The capacitance C1 can be between 20 pF and 0.01 uF...
This circuit was obtained from an American 1980s documentation. The frequency depends on the...