‰  NOW 20 WPM  ‰
WILL OSCILLATE.  FIGURE 2 SHOWS THREE DIFFERENT VARIATIONS OF THE SAME
OSCILLATOR CIRCUIT WITH THE GAIN PROVIDED BY A TRANSISTOR AND AN LC
RESONATOR THAT IS TAPPED TO PROVIDE THE FEEDBACK SIGNAL.  THE RESONATOR
SERVES TWO PURPOSES IT PROVIDES THE NECESSARY PHASE SHIFT AT THE DESIRED
FREQUENCY AND IT ACTS AS FILTER FOR SIGNALS IN THE AMPLIFIER LOOP SO THAT
ONLY THE DESIRED SIGNALS ARE AMPLIFIED.  THE DC BIAS AND POWER CONNECTIONS
ARE OMITTED FROM THE DIAGRAM FOR CLARITY.  TO VISUALIZE THE COMMON EMITTER
CIRCUITS PARALLEL LC RESONATOR, IMAGINE THE CAPACITORS CONNECTED TOGETHER
AND THEIR CONNECTION GROUNDED, AS SHOWN BY THE DASHED LINE.  RF OSCILLATORS
THE CIRCUITS USED IN RF OSCILLATORS ARE DIFFERENT THAN THOSE USED FOR LOWER
‰  FROM PAGE 97  ‰
K2BT/358 K2CO/344 K2EWB/349 K2FL/382 K2HK/365 K2JF/341 K2JMY/368 K2MUB/365
‰  END OF 20 WPM TEXT  ‰  QST DE W1AW  ƒ