hat
Transistor Q2 se itilize kòm yon emeteur-disip bay yon chaj gwo enpedans pou Q1, men pi enpòtan, li bay yon enpedans kondwi ki ba pou savann pou emeteur anplifikatè Q3, ki bay tout pou pran vòltaj anplifikatè a. paramèt ki pi enpòtan nan Q3 se fT,-Wo frekans koupe, ki ta dwe nan seri a nan 200-400 megaèrts. La Yon 2N3904, oswa 2N2222 yon travay byen pou Q3.
eng
Transistor Q2 is used as an emitter-follower to provide a high-impedance load for Q1, but more importantly, it provides a low drive impedance for common-emitter amplifier Q3, which provides all of the amplifier’s voltage gain. The most important parameter of Q3 is fT, the high-frequency cut-off, which should be in the range of 200-400 MHz. A 2N3904, or a 2N2222 works well for Q3.