This circuit uses a stereo amplifier IC in a 14-pin DIL package that requires very few external components to make a complete 2 Watt per channel power amplifier. ..
The swept-frequency oscillator offers an inexpensive source of discrete frequencies for use in testing digital circuits. In this configuration, the circuit generates an 80-second seguence of eight frequencies, dwelling for 10 seconds on each frequency. You can change the dwell time or the number of frequencies. Frequencies can range from 0.005 Hz to 1 MHz. The programmable crystal oscillators, PXOs, IC2 and IC4 can each generate 57 frequencies in response to an 8-bit.....
This is a complete telephone bell replacement circuit with minimum external components with on-chip diode bridge and transient protection..
The two timers in the bug repeller have some interesting characteristics. Roth of them have their thresholds externally set; the oscillator on the left..
This circuit converts a tape recorder into a completely automatic telephone conversation recording instrument that needs no external power source. Voltage at the switch terminals of tape recorder applied to a pair of Darlington-connected transistors, Ql and Q2, will turn on and start the tape recorder. To turn the transistors off, and thereby stop the machine, apply a negative voltage to the base of Ql from the phone line..
To obtain a 1000:1 Sweep Range, the voltage across external resistors Ra and Rb must decrease to nearly zero. This requires that the highest voltage on control pin 8 exceed the voltage at the top of Ra and Rb by a few hundred millivolts. The circuit achieves this by using a diode to lower the effective supply voltage on the 8038..
ICla and IClb are wired as a slow astable multivibrator and IClc-ICld are wired as a fast astable. The output of the slow astable modulates the frequency of the fast astable, and the output of the fast astable is fed to the external speaker via the Ql VMOS power FET amplifier stage. ..
The 50 k ohm pot trims offsets in the devices whether internal or external, so it can be used to set the size of the difference interval. This also makes it useful for liquid-level detection. ..
This figure shows a one-of-two switch with a sunnning amplifier. The video source"s line can be terminated either externally or internally to switch RO. With this termination resistor, a load change of less than 1 0 will be seen by the source when the switch changes state. For this reason, input isolation amplifiers are. not necessary. R4 can be varied to control circuit gain, but should never be less than 1400 0 since the NE5539 is internally compensated for gain.....
This two-chip receiver with minimum external component count has been designed for low-cost fiber optic applications to 100-M baud (50 MHz). The receiver is divided into pre-and postamplifier !Cs for increased stability. The preamplifier IC features low noise with a differential transresistance design. The postamplifier IC incorporates an auto-zeroed first stage with noise shaping, high-gain symmetrical-limiting amplifier, and a matched rise/fall time TTL output.....
This design is for an external signal strength meter that is analog, digital, and audible for mobile transmitter hunters. The S meter also incorporates a gain circuit. The digital LED bar graph display has a very fast response time. The 3.3-KO resistor near LM3914 can be replaced with a 5-K pot to control LED brightness. The S2A position gives a 2:1 gain and the S2B position gives about a 50:1 gain. The calibration pots control the amount of meter action relative to.....
The circuit is activated by an LED/photoresistor isolator (Ul), which is a combination of a light-dependent resistor (LDR) and an LED in a single package. That device was chosen because of its high isolation (2000 V) characteristic, which is necessary because the strobe part of the circuit is directly connected to the ac line.The voltage divider is formed by R2, Ul`s internal resistance, and R3. When Ul`s internal LED is off, Ul`s internal LDR has a very high resistanceon.....
These circuits provide overvoltage protection in case of voltage regulator failure or application of an external voltage. Intended to be used with a supply offering some form of short circuit protection, either foldback, current limiting, or a simple fuse. The most likely application is a 5 V logic supply, since TTL is easily damaged by excess voltage. The values chosen in A are for a 5 V supply, although any supply up to about 25 V can be protected by simply choosing the.....
This free-running multivibrator uses an external current sink to discharge the timing capacitor, C. Therefore, interval ^ may easily be 1000 the pulse duration, t1( which defines a positive output. Capacitor voltage, V^, is a negative going ramp with exponential rise during the pulse output periods. ..
SI is external key switch. The alarm allows a 0- to 45-s delay after SI is operated before the circuit is armed. During this per..
This HF SW receiver preamplifier is comprised of a broadband toroidal transformer (LI-a and Ll-b), a complex LC network (comprised of a 1600- kHz, high-pass filter and a 32-MHz, low-pass filter), L2 and L3 (26 turns of #26 enameled wire wound on an Amidon Associates T-50-2, red, toroidal core), a pair of resistive attenuators (ATTN1 and ATTN2), and of course, the MAR-x device. External power for the preamp can be 9 to 12 Vdc...
This circuit has excellent short term frequency stability because the external load tied across the crystal is mostly capacitive rather than resistive..
This circuit for a compressor uses a high-fidelity external op amp, and a high gain and wide bandwidth. A compensation network input is necessary for stability. The rectifier capacitor (Cg) is not grounded. but it is linked to the output of an op amp circuit. ..
Except for the coupling and decoupling capacitors, IC1 is a complete wideband amplifier that has a fixed gain of 20 dB to 450 MHz. No external compensation is required. since the NE5205 functions as a gain block, two or more cart be easily cascaded to provide additional amplification. In this circuit, which uses two NE5205S, the overall gain is 40 dB...
TheCA3189E is a comprehensive FM-IF system designed for high fidelity FM tuners. It includes a three stage FM-IF amplifier/limiter configuration with level detectors for each stage, a double-balanced quadrature FM detector and an audio amplifier that features the optional use of a muting circuit. The advanced circuit design includes desirable special features such as delayed AGC for the RF tuner, an AFC drive circuit, and an output signal to drive a tuning meter and/or.....
Operational Amplifiers
Computer Systems
Oscilloscopes
Transmitters & Receivers
Sensors & Detectors
ANSI Standards
Low Frequency Amplifiers
Power Amplifiers
Number Systems
Regulated Power Supplies
Analogue Filters
Digital Gates
