A bat with red glowing eyes
The astable multivibrator generates a distorted ramp wave, which in turn gets smoothened out by a filter, driving 2 LEDs with a transistor creating an effect of the bat's ominously blinking eyes.
The circuit can take some time until it starts blinking.
| Ref | Value | Package |
|---|---|---|
| R1, R2 | 10k, 0207 | 110-097 |
| R3, R4 | 47k, 0207 | 110-113 |
| R5 | 330R, 0207 | 110-061 |
| R6 | 300k, 0207 | 110-132 |
| C1, C2, C3 | 47u, 6.3x5 | 123-373 |
| Q1, Q2, Q3 | 2N3904, TO92 | 215-003 |
| D1, D2 | LED, red 5 mm | R: 518-278, FIAL: 518-519 |
| BT1 | 2032 Holder | 819-157 |
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