Work out transistor biasing instantly with clear inputs, formula shown and shareable results.
In an emitter-degenerated stage the emitter voltage is the base voltage minus 0.7 V, so emitter current is that divided by Re. Collector-emitter voltage is the supply minus the drop across both resistors, and the small-signal gain is -Rc/(Re + re) where re is the intrinsic emitter resistance 26 mV/Ie.
BJT bias point
Ve = Vb - 0.7; Ie = Ve / Re; Vce = Vcc - Ie(Rc + Re); Av = -Rc / (Re + 26mV/Ie)
Electrical results are planning estimates only. Verify against the applicable wiring rules (IEC 60364, BS 7671, NEC or local code) and have all installation work designed and checked by a qualified electrician.
It stabilises the operating point against beta and temperature variation by providing negative feedback, at the cost of gain.
Around half the supply for maximum symmetrical swing, and at least a volt or two above saturation across the whole temperature range.