There is an external white noise generator, which is used as a
basis for (TRNG) True Random Numbers Generator. Two amplifier
stages (LM358) aplify the thermal noise signal from inversely
polarized base-emiter BC547. Amplification factor (determined by
resistors 100K/5K6) should be adjusted so that there is no
voltage clipping at AN0 input.
DC-DC convertor generates
+9V2 and -4V2 for analog stage. Coils 2.2ÁH may be replaced by
0Ώ to 100Ώ resistors..