I'm building a small two-sensor line-follower on AA×2 with photoresistors, red LEDs, and an LM393l, very similar to this small LM393 line-following car kit. On glossy paper (16 mm black track) I'm getting edge chatter and occasional false triggers in bright light.
What tweaks have worked for you?
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Simple Schmitt hysteresis: good starting feedback resistor (as % of VCC) with ~10 k sensor dividers at 3 V
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Ambient-light hardening: emitter modulation ~1–2 kHz + RC detect into LM393 (example R/C values?)
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Motor noise: snubbers/decoupling that stop comparator flicker (diode + 100 nF at each motor, bulk + 100 nF near IC—what sizes work best?)
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Sensor spacing for smoother turns on a 16 mm track; threshold balancing tips
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Worth swapping red LEDs/LDRs to IR LED + photodiode at 3 V for better SNR?