| Vintage Part in PDF | Modern Equivalent | Notes | | :--- | :--- | :--- | | | 2N3904 or BC547 | Almost identical NPN signal transistor. | | BC177 / BC179 | 2N3906 or BC557 | PNP complementary pair. | | 741 Op-Amp | 741 (still made) or TL081 | TL081 is better (FET input). | | LM301 Op-Amp | LM301 or LM741 | Check the compensation pin; usually just ignore it. | | TDA2002 Audio Amp | TDA2003 or LM1875 | Check pinout; many are pin-compatible. | | Germanium Diodes (AA119) | 1N4148 or BAT42 | Schottky is fine for low-frequency detection. | | BZY88 Zener diodes | Any modern Zener (400mW or 1W) | Match the voltage (e.g., 5V1, 12V). |
The circuits range from beginner-friendly to advanced. Common categories include: elektor electronics 304 circuits pdf
304 Circuits is a popular entry in the "300 Series" published by Elektor Electronics | Vintage Part in PDF | Modern Equivalent