This common circuit using operational amplifiers was found in the 1993 issue of Radio Electronics Special Projects. The circuit is sandwiched between the pickup and the amplifier input.
This circuit was found in many record players with crystal phono pickups. The output power is 800...
The 8038 is an integrated waveform generator (sinusoidal, triangular and rectangular) from...
This protector was found in an Electronics Now from the 90s. The 250 V transient suppressors are common...