High gain circuits for both RF and audio explorations. Noise locator circuit. Wattmeter circuit. Demodulator probe and preamplifier for oscilloscope applications. Demodulator probe and preamplifier for VTVM applications. Utility audio amplifier. Substitution test output transformer. Sustitution test speaker. Output ind^tor. B-J- source for test purposes. INTRODUCTION You made an excellent choice when you decided to purchase a KNIGHT Signal Tracer. The addition of this instrument to your test bench will greatly reduce the time required to troubleshoot a receiver. The high gain amplifiers (a voltage gain of 91,000 is possible at maximum sensitivity) permit visual and aural signal tracing all the way back to the antenna of a radio receiver. The noise locator circuit will help you to quickly locate noisy controls and resistors, faulty transformers, and intermittent capacitors.