Stk411-210e Circuit Diagram Info

| Problem | Likely Cause | Fix | |-----------------------|---------------------------------------|------------------------------| | Oscillation (>10MHz) | Missing Zobel network or long outputs | Add 10Ω+100pF to ground | | Hum/buzz | Ground loop | Star ground, short inputs | | DC on output (>50mV) | Failed feedback cap (C_fb) | Replace 100µF electrolytic | | Thermal shutdown | Insufficient heatsink | Increase heatsink size, fan | | Low gain | Wrong feedback resistor values | Set Rf1/Rf2 = 22k/1k |

Usually 100µF and 0.1µF placed near power supply pins to reduce noise. stk411-210e circuit diagram

| Component | Value | Purpose | |-----------|-------------|----------------------------------| | R_in | 47kΩ | Input impedance setting | | R_f1 | 22kΩ | Feedback resistor (Rf) | | R_f2 | 1kΩ to GND | Sets gain (internal + external) | | C_in | 10µF (elec) | DC blocking input capacitor | | C_fb | 100µF (elec)| DC servo cap for feedback loop | | Cc | 100µF | Power supply decoupling (each pin)| | Zobel R | 10Ω 1W | High-frequency stability | | Zobel C | 100pF ceramic| Suppresses oscillations | | C_supply | 1000µF | Main filter cap (per rail) | | Problem | Likely Cause | Fix |