Here is a simple audio amplifier for receiver projects. Gain is more than 65db. Easy to construct and good enough for room filled volume. Not meant for hi-fi applications or large volumes as it produces distortion at higher amplitudes. Very satisfactory for Radio Amateur work. Try it - you'll like it!!

R2 should be changed for different supply voltages - for 6V operation, R2 should be about 68 to 120 ohms. For 12V supply, it can be around 270 ohms. Choose the best value for your application. Value is not very critical but avoid large cathode currents.