Schematic Diagram

With the schema shown in the following schematic diagram, both channels of this stereo preamp is constructed using  RCA CA3052 quad AC amplifier.  this pre-amplifier schema is featured with tone control (bass – treble). Make a similar schema to complete the other channel, since the schema for left and right channel are similar. To be high-fidelity, total harmonic distortion should be kept minimum, this schema gives less than 0.3% distortion level at  at 1-kHz testing signal with 1-V amplitude.  

Gain or amplification at 1 kHz is 47 dB,  and the tone control will curve the response with 11.5-dB boost at 100 Hz and 10 kHz at maximum bass and treble boost.  For minimum bass and treble knob position,  the attenuation will be 10dB  at 100 Hz  and 9dB at 10kHz. This schema is operated by a single ended supply for wider range environment. Inputs can be from tape recorders pickup or magnetic-cartridge phonographs.

This is a simple design, can have excellent results, he is a recipient of regeneration, if you have never built any receiver, this is one you will build Easy. The schema described is simple and has many limitations in sensitivity and selectivity, but is able to receive signals from radio amateurs (40m or 80m) in SSB and CW, and as output using a small headset crystal. 

He will have a saturation if there are strong stations available on AM broadcast band of 41m at night.L1 is a small toroid T50-2 (red) with about 18 to 20 times (40m) or 35 to 40 times (80m) in the main winding connected to the FET with a single coupling schema facing the antenna connection. 

The center tap is about 20% of the primary winding. C1 is adjusted to set the radio band to the 40m and C2 then acts as a fine tuning within the band.The supply of 12 to 14V, R2 should be increased 5K6 or 6K8 output will be higher and similar sensitivity to-100dBm (about 2uV).