Circuit uses two overdriven FET amplifier stages in cascade. Designed for use with load of 10K or larger. Tap at 5, 10 and 15 turns from L2 end. L4 — 36 turns No. 24 enam. wire on Amidon T-68-2 toroid core.
Temperature sensitivity of FET tional AM97C11 quad FET and LM324 quad can be reduced by using silicon resistor for opamp gives tracking gain control having 40-dB opamp feedback resistor HI. — «FET Databook,» range. With S 1 normally open and S 2 normally closed, circuit operation is normal. If switch positions are simultane- ously reversed, response remains flat regard- less of positions of bass and treble pots, center- frequency gain remains unchanged, and phase shift is unchanged. Location of tone con- thermal compensation. — «Circuit Ideas for RCA opamp to drive complementary-symmetry trols in feedback network improves signal-to- Linear ICs,» RCA Solid State Division, Somer- power-output transistors. Circuit has infinite input impedance and zero bias current. Diodes rectify noise from limiter or discrimina- tor of receiver, producing direct current that turns on Q, and thereby clamps opamp off. Push- pull emitter-follower stages are connected to give symmetrical low output impedance on both positive and negative portions of audio waveform.
Similarly, a resistance of 1R5 is 1.5 ohms, 1M2 is 1.2 megohms, and 3n3 is 3.3 nanofarads. Coupling strips on base and collector of transistor are 0.25-mm brass shim stock. Shield mixer circuit and use shielded cable for all input leads to avoid pickup of 60-Hz field by high-gain opamp. Operating volt- age is supplied through coax feeder. R1 isolates signal energy from ground, and C2 keeps DC voltage out of receiver input. Tap at 6, 12 and 18 turns from L3 end. M1 — to 1-mA dc meter, 1-1/2 inches square. Voltages of 1N4002 silicon diodes are proportional to logarithms of their currents, which in turn are proportional to forward and reflected voltages.