ELECTRONICS

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ELECTRONICS 68



Jan 8    		 FB protects power supply
       		Data errors detecting
                           Diodes limits input slope
            		Transistor bleeder
       		Zener power supply
       		Tunnel diode in PFM
 Jan 22 		Fast charged  batteries (Ni-Cd)
 Feb 5 		 Wien FET modulated oscillator
        		IC fast recovery FF
Ele 68  		Inverted triode insulation meter
        		SCR regulator(zener reference)
        		Grounded base transistor mating logics
     		 OPAMP drift compensation
 Mar 4 		 Trafo divider for UHF frequencies
        		Schmitt trigger digital IC
        		Bridge rectifier  clips surges
       	
 Mar 18		 Staircase steps flat with a FET
        		Metal detector inductor
        		Photo printer UJT-SCR timer
     		 FB for low capacitance bio probe
 Apr 15 		 CMR optimization in OPAMP (Theory)
Ele 68  		FFT (Theory)
 Apr 29 		A/D triple ramp converter
 May 27 	Inverter  sine wave DC/DC (switcher)
        		Gated triacs clean AC switching
        		Pulse generator very stable
        		Active filters    Part 1
 Jun 10 		FET voltmeter for transients
        		Boost OPAMP with transistors
        		Zener simulates muscle signals
        		Active filters;girators
 Jul 8 		Filtering noise in weak signals (Lock-in AMP)
        		Voltage comparator
 Ele68		Zener protects series regulator
        		Diodes in multivibrators
 Aug 5		 Transistor speeds up charging solenoids
        		Dwell angle diode & Ohmmeter
        		IC gate controls triac with a audio trafo
        		Current source nodulation inÿOPAMP.
      		OPAMP boosts induced voltage
        		Mercury lamp ballast (Theory & circuits)  switcher
 Aug 19		 FET & UJT in linear oscillator
        		FF isolates pulse from bounce
       		Schmitt trigger DTL NAND
        		SCR monitor for discharge rate of cells
        		Ripple calculation
Ele68  		EXOR( diode bridge & transistor)
        		Triangular wave generator
 Sep 2		OPAMP voltmeter
        		FB keeps torque constant servo DC motors
        		Active filters Negative impedance converters  NIC
 Sep 		16 OPAMP simulates indutance
        		More power with zeners+trasistors
        		Parallel-T bandpass filter produces voltage gain
        		Active filters NIC (cont.)Circuits
        		Bootstrapping OPAMP
 Oct 28 		Increase range of relaxation oscillator
Ele68   		MV with Darlington
        		MV fast rise time  (20 nS with 10nS rise)
 Nov 25 		 UTJ protects OPAMP against transients
 Dec 9		 Squelch gate reduces AMP drain
        		Transistor cancel indutive load effects
       		Multiplier replaces custom trafo (power supply)
        		Active filters:OPAMPs
 Dec 23 		Voltage regulator with 2 AND gates (uL914) chopper (switcher)
        		FET pre-AMP (G=1000 .5 to 300kHz,low noise)3 transistors
        		Eliminate excess of inductors  in filters
        		Comparators in threshold converters (sine waves zero)


ELECTRONICS 69

Feb 3 Active filters Part 6 OPAMP Feb 17 Safety of medical instruments Active filters Part 7 Analog blocks Mar 17 Peak detector Track & hold diode bridge switched Mar 31 Miller sweep with active load PNP-NPN zener with variable impedance(oscillator?) Active filters: NF Part 8 Apr 14 DC/DC converter(diodes,MV,10 to 100V,70%,10KHz) Photomultiplier gain tempco compensated Ele69 Active filters Part 9 Nonlinear elements Jun 9 FET probe (two conductors) Thermistor linearity circuit Unijunction protects transistors Log circuit eliminates diode bulk resistence effects Jul 7 DC restorer clamp Binary input to AC output(servos) Jul 21 Constant duty cycle pulse train frequency variable Aug 4 Eliminating bounce from switches Transistor phase detector Ele69 Inverted transistor switches DC voltage RC filter pulse train duty factor controlled Sep 1 Asynchronous pulse in tape data control Pulse modulator regulates valve closure Oct 13 Diode generator for complex functions Heat failures of thermocouples Oct 27 Irregularities in small shafts Monitor for power failures(3 phases) SCR preregulator in power supplies(zener DC trigger) Multiplexers as logic circuits Nov 10 Optical isolator speeds data transmission 2 stages peak-holding stores picoS pulses Ele69 Design hysteresis circuits Nov 24 Wide range FM discriminator(no tuned) AC source drives tape stepping motor 2 phase oscillator (Matsushita) Dec 8 MV separate pulses by widths D/A Converter with TTL gates Capacitor sets shape of ramp generator Dec 22 FF stabilizes A/D converter output Transistor chopper Scope reference encoded waveform(delayed sweep)

ELECTRONICS 70

Jan 5 Filter Wien for AD converters (line noise) Digital display resistor matrix Underwater pinger oscillator(UJT) Feb 2 Chip substrate temperature regulator (CA3045) Feb 16 FB Checks thermal resistence Zener in FB for symmetrical clipping Gyroscope derived rate circuit-FET gate Frequency meter,comparator & phase meter Mar 16 Zener bootstrap for DC AMP MOSFET transient free linear gate TTL controls large signals in commutator Mar 30 Negative impedance controls motor speed El70 Signal detector for 5V supply Low offset chopper (inverted transistors) May 25 FET variable gain AMP Q multiplier in audio analysis DC/DC converter for + or - bias (switcher) Jun 22 EXOR for phase locking Motor dynamic braking emf reverses rotation Jul 6 IC minisize bias supply oscillator (74H00 ) Switching regulator drives Nixies Program for band pass filters & low pass . Examples Jul 20 FB triggers SS from both polarity edges FET phase detector as F/V converter El70 FET variable resistance gives 90 phase shift Switching regulators Aug 3 Wave squarer shifts phase up to 360 Aug 17 Comparator & MV add up to linear VCO (V/F) Charts for designing current sources Aug 31 Fail safe flame detector Hex inverter picks data from noise spikes(pulse width discriminator) FET converts triangles to sines Sep 14 Resetting at power on El70 Diodes prevents power loss & burnout in converters Oct 12 UJT stable VCO DC/DC converter design (switcher) Oct 26 Programable digital filter functions Nov 23 Limiter preserves phase over 50dB range Optoelectronic switch monitors line power Dec 7 FET tunes active filter (double T)

ELECTRONICS 71

Jan 4 Battery discharge triggers alarm & shuts off Photocell measures pulsed laser power Jan 18 High voltage pulses avalanching transistor SCR crowbar protection Wien oscillator (lamp, .5% HD,MC1454) Sequencial gate dont chop odd-length pulses SS saves power Ferrites cores for noise suppretion FET cascode optimizes differencial AMP Feb 1 AMP for OPAMP noise measurement FET input voltmeter Audio AMP with 1V cell Feb 15 Counter sifts phase Ele71 Series limiter tracks signal,finds symmetry OPAMP delay & shape data Mar 1 Josephson junctions(uses & effects) OPAMP splits power supply MV range 10000:1 (VCO) AC noise meter (Ripplemeter) Mar 15 Contact bounce suppressing FB speeds phototransistor response Mar 29 Diode thermometer High voltage supply (.001%,500 to 3500V,1mA,diode bridge & trasist.) OPAMP booster crossover free Apr 12 AC transfers DC isolated( chopper & trafo ) Ele71 Compact low frequency antenna (dipole) FET SS long pulse Apr 26 12 hour digital clock EXOR needs no supply High voltage AMP (very fast) Notch filter (movable zeros & fixed poles) May 10 FET clamp for 10MHz Impedance-lowering OPAMP speeds filter May 24 Photoamplifier x photomultipliers FF pair synchronizes pulses & floats clocks (JK FF) RF preAMP low noise Jun 7 Four layer diode out regulates zeners by 5:1 Diodes stabilize FET gain to 1% over 100C range Ele71 Dual NOR gate + transistor generates 12 functions Design of active bandpass filter Jun 21 Gated clock cuts counter delay to 60 nS Foldback current power supply Digital circuit filters highs,lows & bands Design FET differencial inputs AMP Jul 5 Oscillator controls pulse width & spacing AMP slew rate curves Jul 19 Tunable active filter constant Q (150 to 1500,Q=30,dual pot,3 AMP) Detector measures phase 360 range Counting by halves simplifies odd-order couter Aug 2 Null indicator LED pair (Ì+ .2mV) Wide range MV IC frequency doubler (10MHz) Ele71 Design curves for AMP analysis (RF) Aug 16 One variable resistor alters filter Triggered sweep generator responds to 100nS spike Broad band pulse generator(FET + NAND,.3 to 10MHz,20Mohm pot) Aug 30 Pulse generator (4 inverters,on & off variable) Low frequency oscillator with subharmonic syncronization(710) FB zeros DC level of diodes gating circuit (tracking filters) Electrometer low current measuring (FET &ÿMOSFET inputs) Sep 13 Capacitance meter sawtooth reference Phase countinuous frequency shift oscillator Odd order counter symmetric Sep 27 SS trigger for slow pulses Ele71 FET supply tests bipolar current gain FB pot extends MV duty cycle Oct 11 One of eigth decoders( test & corrects parity ) Line driver isolation AMP Diode & SCR protect multiple voltage supply Dual OPAMP comparator controls ramp reference(MC1437l) Oct 25 Positive & negative gates trim logic High impedance driver boosts detector range(455KHz) Scope curve tracer (low current only) Filter design (equations- theory) Nov 8 Transistor matrix driver Switching regulator (LM311,7400,limit 10A,1%) FET current source for ramp Dec 6 Interrupt register secures data Ele71 V/F converter with four layer diode IC transistor array compensates temperature Dec 20 PLL sample loop divider VCO Digital phase shifter maintains quadrature (PLL) High gain instrument AMP

ELECTRONICS 72

Jan 3 S&H Aperture time error nomograph SCR reset for integrators MOSFET FB control in audio oscillators Jan 17 Bootstraped capacitor in UJT oscillator(.05% 0C to 55C) FB current switch divides RF by 20 Tunable filter varies Q (Wien ,double pot ,Q 2000) Jan 31 Staircase generator (.1%) Schottky diodes gates AND Feb 14 Doubling OPAMP summing power Square wave generator Two adders form BCD subtrator Ele72 VSWR detector protects RF AMP Feb 28 Transducer preAMP low power (FET input,1.5V) Ele72 Differentiate & count to find frequency error FB latch reduces memory recovery time Transistor testing (gain,gm,Icbo,etc) Mar 13 Voltage reference (741,6.4V zener,1.9ppm tempco) Fast switching modulator reverses UHF phase ECL gates stretch range of oscillators Mar 27 Series connected OPAMPs null offset voltage Linear signal limiting with FB multiplier (limiter) Compare binary numbers Finding open loop gain without opening the loop Coaxial buses help suppress transients Conductive heat transfer problems Apr 10 Unclocked logic makes decisions Ele72 H/W converter for analog samples 400Hz power supply MOSFET bias for 0 tempco Film for scope pictures PWM replaces resistence in potentiometer Apr 24 Laser interferometry (dual ramp ratio divider) Regulating HV with low voltage transistors OPAMP multiply time constants SS & FF detects frequency bands Active resonators in active filters (theory & pratice) Measuring HF transistor gain Ligth pen use in CRT & scopes Testing IC chips (high speed) May 8 SS divides by up to 30 Ele72 MOS data saved by battery (memory) Triangular wave generator (8 decades ,.01 to 2MHz,6 transistors) Timer 555 uses(PWM,missing pulse detection etc) FET input OPAMP reducing bias current May 22 SS with output comparator Series resistance improves pot linearity BCD addition in digital PLL OPAMPs drift matched Testing multioutput power supplies Jun 5 OPAMP list Frequency synthesizer Linear amplitude modulator FET audio squelch circuit Settling time measurement with time delay Ele72 Pseudo random pulses sequences & time delay Jun 19 Diode thermostat (.05C) Test A/D converter MV with complementary outputs Digital recording heads - cares & types PCB edge connectors costs Jul 3 Schmitt trigger prevents clock train overlap Broadband limiter is phase transparent Pulses number preset generator Jul 17 Frequency doubler for any waveshape OPAMP cancels video transients Stable pulse generator (Progr.UJT) Computational module (Log,AD433) Spark gaps-uses Jul 31 Logic probe LED display(MC1048) Ele72 Scope 4 channel display Control OPAMP gain with one pot IC Schmitt trigger(7413) Aug 14 Logic gates as D/A converters (7405 open collector) TTL gates in pulse height analysis LED voltage sensor Digital ICs set temperature compensation for oscillators Power losses in AMP Aug 28 Wired OR DTL gates in multiplexers Integrator resets itself (.1%) Wien bridge in notch filter (60dB) Sep 11 MV clock obeys digital commands OPAMP with FB makes full wave rectifier Active filter with band & frequency control Ele72 MOSFET threshold in one measurement Low pass filter design(graphic) Sep 25 Logic converts synchronous motor to stepper Ring counter eliminates false gating signals Comkplementary output improves OPAMP responce Capacitor self-ressonance frequency charts Vanadium oxide tempco sensor (.05C) Oct 9 Metal oxide varistor for transients Generator varies pulse rate & width Photodetector senses motion MOSFET squaring circuit Time measurement for capacitor,resistor & indutance Low drift OPAMP analysis Oct 23 FB linearizes resistence bridge Ele72 Soldering iron for constant temperature probe EXOR gate for bidirectional SS Digital panel meter Active filters tables (LP & HP) Vide Apr 12 corrections V/F module(4701 Teledyne,.015%) Optical trigger for scopes Nov 6 Optical measurements(Photometry & radiometry) FET OPAMPs MOSFETs as multiplexing switches Motor stepper driver Voltage tuned filter(bandpass) Instrument OPAMP for computer inputs Suppression network for SCR converter Test power supply Ele72 Infrared intruder alarm Nov 20 Decoder for modulated pulse widths CMOS sums tones in electronic organ Transistor gating cuts signal delay to 100pS Multiplying scheme as alternative to count down timers Wave form generator (8038) Dec 4 Staircase generator 4A power supply Binary division gives harmonics Zero correction in OPAMPs Power dissipation in microcicuits Design of front panels LED as sensor Dec 18 Tachometer squelches point bounce Ele72 AGC RF threshold detector Phase comparator for servo loops(FF) Make your switches for boards Timing circuits for noisy environments

ELECTRONICS 73

Jan 4 Doubling voltage with cascode transistors Linear RF modulation with OPAMPs LP & HP tunable filter Jan 18 Synchronous ramp generator MV with one capacitor Automobile ignition system Feb 1 Programable SS Power with 741 (22W,+30 -30V) DPDP switch solid state Design of program controllers Approximating wave forms with exponencial functions Feb 15 Negative resistence generator Modulator tests hi-fi AM tuners Ele73 Programable MV (four functions) Digital filter varies passband Mar 1 High power counter drives 20W loads CMOS monitors Ni-Cd batteries Switching large loads with logic signals DVM as linear ohmmeter Filter bandwidth nomograph gives sweep rate limits CMOS gate as adjustable divider (4001) Mar 15 Gate bias for NMOS from 5V (Chopper) Control duty cycle & rep rate generator(10 to 10kHz) Power supply foldback Mar 29 Time delay extended Current sharing regulator power supply(LM340,78xx) Up/down counter syncr. Ele73 Shortcuts with pocket calculators Versatile breadboard Apr 12 DC motor control (armature resistence) Network is filter or oscillator Monitor for battery voltage Scope graticule with 3dB points Thermally adjacent diodes balances transistor Apr 26 V/C converter (4 -20mA) Binary RF phase modulator Data averager for panel meter Scope detects narrow pulses Precision comparator circuit May 10 Varying comparator hysteresis Circular voltage divider Ele73 Tank circuit steps up CMOS driving voltage SW generator (50Mhz) Cable tester Capacitor performance (tempco & freq.) May 24 Charge balancing A/D converter HF transistors temperature compensation Gating circuits monitors real time inputs Audio limiter (lamps,AGC,compressor) Capacitors for AC power OPAMP in active voltage divider Jun 7 Road ice indicator Zener+OPAMP reference (10V +- 7mV,0 to 75C) Elminating offset error in sense AMP CMOS crystal oscillators Ele73 Pulse generator CMOS FF Chopper OPAMP Jun 21 MOSFET crystal oscillator Varistor improves AGC HV regulation with low voltage zeners Uses of the 741 OPAMP Temperature control with timer + thermistor Stretch duty cycle of 555 timer Timer + resistor SW generator Timer monitors battery Auto burglar alarm with timer Timer temperature/frequency converter Timer as line receiver Timer delays Ele73 6000V/microS OPAMP (LH0063) Switched power supply Jul 5 TTL synchronizes clock A/D converter gives logarithmic output Analog multiplier/divider for frequency locking Quad NAND yields two frequency clock Control tape recorder speed Trim fast FET OPAMP (twisted wire) Jul 19 Capacitor corrects drift in data AMP High speed follower (1 nS delay,4 trans.) Mark space demodulator with active filters Check wired-AND Ele73 D/A converter differencial linearity Power rating of variable resistors Aug 2 Series-shunt regulator power supply Motor speed sampling regulator control Digital transient suppressor Staircase generator digital Automatic erasure of storage scopes Chart for intermodulation products Aug 16 Chopper OPAMP (Texas 088) Switchers:Theory & Pratice (555 & 550) Pulse generator with binary input AGC over two decades OPAMP test circuit (5 DC tests) Ele73 Electronic dice Aug 30 Frequency discriminator with SS & FF CMOS counter for 2Ã 70 pulses First event identification Power supply design simple AC wave form table conversion Sep 13 A/D converter with auto zeroing Boosting IC regulator current Digital clock dual mode display Sep 27 Trimming networks impedance-sensitivity nomograph Triac trigger precision driver (Audio) Multiplier for wattmeter (signetics 5596) Power supply variable (5V 8 to 17V) Chopper OPAMP MOS (HA2900) Ele73 CMOS switch for S/H (4016) Power circuits (diodes & SCR) Designing logic with microprocessors Oct 11 Miller integrators as signals separators CATV transistors as low distortion VHF preAMP Switch controls auto air conditioner D/A converter from transistor array Optoelectronics & optical spectrum Beam thickness in CRT display Test thermal resistence sequencer Scope triggered sweep (555) PicoAmpere cares Oct 25 Boost a 709 (300V/microS,15MHz,300000G) 555 Schmitt trigger Ele73 Pulse width discriminator (NOR & SS) Test clip logic analyzer(Fluke Trendar) Nov 8 Digital phase shifter demodulator Composite dual OPAMP improves response Power supply zero ripple output Design thermal demands - Radiators & heat pipes IC plastic power devices Ladder type networks analysis HP 35 Polynomials & their roots Storing two constants Statistical analysis RF wattmeter up to 50 W Nov 22 Two wire link multipoint data NanoS addressing system (registers) Ele73 Digital filter (comb) Gate threshold difference gives inicializing pulse Scope with 8 logic inputs Gray scale images on storage tubes Display Flashing lamp alarm Dec 6 Digital DVM design - signal conditioner etc Dec 20 D/A converter (Adder & shift register) DC restorer for video Regulator for standby supply( high amper.) Phase difference digital meter Thermal detection with liquid crystals AC source with audio AMP Thermal analysis of power semiconductors (Theory -Heat sinks) Temperature limiting boosts regulator current (723) Ele73 Digital phase shifter handles 5:1 bandwidth Voltage discriminator .1mV resolution (711) Norton quad AMP(LM3900,circuits) Building your DVM (2 2/3,Motorola ,staircase ramp) Eletrometer FET (2N5909 & LM308) DVM as current source

ELECTRONICS 74

Jan 10 AGC thump in AMP Algebraic inversion with transistor array (CA3086,Log) LED voltage regulator LED voltage indicator Jan 24 Forced air cooling -Thermal design IV part Power supply 10A (723) Multiphase clock nonoverlapping pulses PLL for varying conditions Impedance simulator for loads UJT with PNP-NPN pair Basic program for resistive DC cicuits Feb 7 External gate doubles counter speed Switcher DC/DC converter current spiking free Ele74 SCR crowbar (723) Microwave leakage monitor Nonsequential counter design Feb 21 Discriminator cleans signal noise Controlling AC loads with CMOS (4016) 555 auto voltage regulator Trimming closed resistor loops Selection of A/D converters Mar 7 HP 35 statistical analysis Transistor array as thyristors CMOS touch switch (4016,4044,4009) Switching regulator constant current (723,1A) Mar 21 Cassete recorder as phone monitor Ele74 State variable filter(dual OPAMP) LED null for 555 resistance bridge Static RAM reducing power drain Logic gate as FF Isolator scope circuit for checking ungrounded voltages(optical) Apr 4 Extend timing of two AMP integrator Ignition system limits RPM AGC FET OPAMP wide range (2 FETs bridge) D/A current steering(theory) Apr 18 Simplify binary number conversion Storing data in a cassette recorder Ele74 Music with IC timers Tables to equations for calculator use (examples) Logic tester for ICs Scope probes;their uses Monitor for 7 segments display May 2 RF detector Schottky diodes Crowbar senses load voltage Simple gating marks both pulse edges Computers networks on computations Measuring access time of ROMs Eliminating stray signals in gain switched OPAMPs May 16 Thermal design : map heat flow (Theory) Part 6 Metronome Ele74 Two color LEDs switch each other May 30 regulator protects pull-up transistors Tone bursts generator (2 555) Adding two BCD numbers In circuit IC tester for TTL & CMOS (4009,LEDs & diodes) Jun 13 Noise blanker cleans audio Variable voltage with adjustable tempco (.7 to 13V,-.3 to +.3%/C) Probing noise from Hz to MHz (Probes details) Two gates FF Polynomial expansion beats calculator display limits Jun 27 A/D converters in two chips(LD111,LD110,DVM circuits) Combination lock Serial multiplier for two five-bit numbers Ele74 Power supply donw to zero Thermal design : Heat exchangers in PCB boards Part 8 Unusual jobs for capacitance coupled logic Test optical isolators Fan out of CMOS buffers Jul 11 Biasing improves clamping OPAMP LED shows beat frequency DC differential voltmeter resolves 1 microV ( Calibrator MIT) Jul 25 A/D converters (theory) Teletypewriter interface (Baudot data ) Diode pair senses differental temperature Ele74 NanoS pulses with TTL SS (74121,74S00,rise 2nS) Driving LEDs with CMOS Trasistor capacitance multiplier Measuring impedances at operating levels (complex,Smith chart) Aug 8 Rectifier with three matched resistors Decimal output from seven segments (74154,7404,7400,trans.) Broadband PIN diode attenuator (AGC) Design class A AMPs (Theory) CMOS Schmitt trigger uses Regulators protection Aug 22 DC/DC converter voltage doubler (555) SCR zero cross trigger limits power Ele74 Analog peripheral in minicomputer chassis Measure optical coupler speed Cable tester programable Simulating an NPN/PNP pair for HV switching Sep 5 Indicator for PLL PLL correction Sept 5 74 Window comparator with one OPAMP Check electrolytics with voltmeter 16 bits D/A comverters Listening to magnetic fields Sep 19 Two components ligth sensor (Phototrans. & const.curr. diode) Coding A/D for sign & magnitude Control periods of 555 Ele74 Modeling the bipolar transistor Part 1 Diagonal axis to a scope (3D) Selfpowered comparator warns when signal exceeds limits Oct 3 Bipolar power supply (2 741 symetrical) Filter programed digitally Transients in FET analog switches Cable tester Triple Darlington with low saturation voltage TTL level tester Oct 31 Modeling the bipolar transistor Part 2 Coherent phase modulation to 100MHz(step recovery diode) Single switch regulates number of pulses (burst) Ele74 Power AMP as AC power supply Two circuits indicate synchro shaft position Standing wave ratios & impedances values (swr) Nov 14 Analog gate & zener isolates 70dB (80MHz)(double balanced mixer) OPAMP compares bipolar voltage magnitudes Regulated power supply with one quad IC (0-20V,1A,.02%) IC comparator with FB as clipper (squarer) Integrated temperature transducers Peak detectors(Theory & circuits) Low frequency discriminator uses a analog delay Nov 28 One transistor bias power output pair Timer circuit for power on reset Ele74 SW generator constant duty cycle (555) 7 segment code to decimal Temperature transducers output display (charts for types of) Gas & smoke detector with MOSFET Keyboard with a pocket calculator Dec 12 Rectifying with variable gain(1KHz) Power failure detector(fast) MV with SCR for lamps Dec 26 Slow counter with a calculator chip Window comparator temperature compensated Plating cell timer Counter for microprocessor interrupts Step function generator (7441 decoder & resistors) Ele74 LED brightness control (555 & CdS cell)

ELECTRONICS 75

Jan 9 CMOS specifications FB keeps LED constant Latch interlock switches Wien oscillator & diodes (741,1N914,.3dB,diodes on Wien!) FET programs OPAMP for invertible gain PLL with dual bandwidth loop (fast) Soluble mask for PCB solder Jan 23 Water jacket induction furnace AC RMS converter (Thermoelement BB4131 BurrBrown) Ele75 D/A converter controls active filter Intruder alarm with two oscillator(auto,capacitive) Frequency divider & OPAMP generates sine wave Designing microprocessors with discrete logic Part1 & 2 Sine wave clock :time delay & others Inductor for memory driver Power supply transients control (Spikes on turn on & off,triacs) Capacitance measurement with a frequency meter Feb 6 Safety barriers (Fire & explosion) 555 timer compensation (capacitor tempco) CCD array overlapped clock phases generator IC tester CMOS overvoltage indicator(May 30 1974) Increasing a instruction set Ele75 Field strengh (150KHz to 30MHz) RF Feb 20 Phone line ringer optocoupled Power supply 0 to 38V,2A,723) Rectifying small signals (comparator & CMOS,3MHz,NE529 20nanoS) Reference voltage (zener & OPAMP,.001,1N829,bipolar) Two color LEDs status indicator Touch keyboard TTL strobed(74150,74161,74194) Preferred components table Mar 6 Boost integrator time constant with a transistor(beta multipl.) Keyboard interface (5740,2812,74125) Digital command inverts signal FM demodulator (NE563) DC/DC converter(ML4270,MV & compar. Ele75 CCD & analog filtering Mar 20 Frequency calibration with TV color reference Timer warns tape run-out Antilog generator keeps VCO linear (.4%) Diode silicon as radiation sensor( gamma & high energy X rays,10rads CMOS FF various uses (SS,pulse limit detector,generator etc) Solid state temperature sensors (Theory & circuits) Factors for correcting AC power waveforms HP-45 RF AMP design Apr 3 Waveform from linear segments Temperature to frequency converter (diode,0to100C,.3%) NOR gate starts shift-register loop (Only one 1 in the loop) Four point tests solder joints Ele75 Variable capacitor from PCB boards Apr 17 A/D converter 10bits (compar. + current source+clock) Frequency meter overrange Frequency doubler (7404,7400) May 1 Data domain digital instruments -logic analizers SCR noiseless buffer Diodes protect logic level translator Double ended power supply CMOS phase meter (4011) Check TTL wire bonds Low drift instrumetation AMP May 15 CMOS technology V/F converters (Theory) Ele75 Isolation with optical couplers Tripping of protection circuits in power supply 555 as switcher (-10V, 10mA,5%) DIP switch isolates faults OPAMP + DVM as fluxmeter (search coil,integrator) Seven segments shows Roman up to 5 Telephone plays a tune May 29 TCS electronic anesthetic Phase lock indicator (LED) ECL oscillator 10 to 50MHz (MC10116) Monitor for car battery Jun 12 SS width is programable Current & power limiter for switching transistor Ele75 555 switcher (dual 15V from 5V,10mA) Optical sensor overcomes ambient light Calculating resistances for sum & difference OPAMP Jun 26 Microphone preAMP gets power through signal cables 7 segments to decimal or BCD (converter) Capacitive transducer for tension in muscle fibers(555,5608 VCO) Lambda diode: P & N FET pair negative resistence device LED as CRT in scopes Plot total loads in recorders (sum constant currents,FETs) Mixed dielectrics improves capacitor tempco Compandor XR-2216(60dB) Jul 10 Gain of OPAMP by digital control HV pulse train (4KV,series conection,parallel charge) Ele75 OPAMP measures diode capacitance(LM324) Convert numbers decimal to any base Coaxial loss by three measures Jul 24 D/A converter in OPAMP programable gain control SS with FB loop for constant duty cycle Optocoupler converts AC tone to logic levels Calculator sums two sets of numbers Adaptative motor starter delays Table for designing PI attenuators Aug 7 Audio HD (.001%, Matsushita) Instrument OPAMP sums 6 inputs Touch tone phone receiver with AGC & filtering Optoisolator curve tracer Ele75 Bucket brigade clock CMOS divider Aug 21 OPAMP outputs with fixed phase difference Tapered audio volume control ECL tuned oscillators Phase modulation techniques in PLL ( Theory ) Edge triggered FF make 360 phase meter Graphs for aperture time in A/D converters Sep 4 Phase sequence detector PreAMP for LF & VLF (Omega receivers) Unity gain 50 ohms driver (10MHz Organ oscillators (dividers) Beta at constant power ( Transistor) Thermistor as temperature regulator Ele75 Tone logic probe Sep 18 Digitally controlled OPAMP Programable bilateral current source Electronic graphic symbols How to reduce noise pickup in ICs Ignition dwell angle (VOM & circuit:LM3900) Welder timer Oct 2 Digital audio sine waves (4051,4024,4030) Oscillator clock for AC power fails Switchers in power supply Active filter has stable notch (tone signalling) CRT terminals to printer lines - optoisolation Resistor measure with A/D converters (Ratiom.) Ele75 555 controls life test cycling Oct 30 VCO with 8038 (741) Converter for teletypewriter driver FET P & N Lambda oscillators(RF & audio modulation in same) FFT differencial phase shifter (algorithm) Nov 13 Sums BCD numbers (hardware) Timers in DC/DC switcher converter (555,300mA,8-10V,.5%) First of four responses Active load constant power DC (AD435K) Dec 11 Multiplexed detectors for water leaks IC orientation current tester Dec 25 Scope display of 8 signals Process control with lead & lag compensation Logic selects most intense signal (RF) Lead & lag compensation of process control(Theory & circuits) Ele75 DVM 2 1/2 digits quad norton OPAMP

ELECTRONICS 76

Jan 8 Current source grounded load 555 triangular waves Jan 22 No inductors DC/DC converter (74C901 inverter) Audio AGC with photocoupler(CLM6000 Photoresistor) Indutive proximity detector Feb 5 State variable low distortion oscillator(FET,.02%,quadr.,quadOPAMP) Video distribution AMP (LM318,LH0002CN) Feb 19 Transistors level voltage shifters(common gate or base) Schmitt trigger with a comparator Ele76 High power pulsed transistor tester (scope) 555 FF varies with manufacturer Mar 4 Optical isolators in linear circuits (Theory & circuits) Mar 18 Temperature regulator:Same transistor senses & heats IC voltage regulator expands scale meter Apr 1 Nonlinear lowpass filter rejects impulse signals (rise time) FSK modem interface(4020,4013,4011,4016,LM3900,950KHz Xtal) May 13 Pot & timer control up/down counter (set point p.ex.) Regulator shares load with transistor (723) Apr 29 Plasma probe (current in OPAMP) 555 multiple scope display Electronics abbreviations May 13 Diode & transistor thermometer Ele76 Touch switch enters data V/F with 555 & current source Jun 10 PLL in synthesizer -pulses period in up/down counter Back & forth scanner in printers Hexadecimal display (large) Jun 24 OPAMP oscillator NTC (nao convencional!) CMOS auto intrusion alarm (switches) Hardware helps in tracing progams(interrupt) Jul 8 7490 as N divider Square root circuit(OA91,BA100,741,1% 0 to 100V) Tail biting SS keeps ligth on (555) Jul 22 Synchronize pulse with clock in control Ele76 Frequency doubler with SqW output TTL logic tester displays H or L Calculation for filter capacitor value Speeds FM tuner measurements Aug 5 Transistors parameters multimeter measurements FM deviation with a spectrum analizer Scope triggeered register freezes serial data CMOS reset circuit Analog divider (555,FET,741,V/F,amplitude modulator) Aug 19 Optical coupling isolation circuits (Theory & pratice) Sep 2 Notch filter (Andreieff,one pot) Ele76 Calculator HP25 in spur analysis Log ratio measures high resistances Sep 16 3V powers nanoS pulse generator Flash A/D converter (comparators & inverters) Voltage doubler power supply(6.3AC,8V,16V,-8V) Buried zener with heater(LM199,1ppm tempco) Frequency counter simple Sep 30 Scope sweep as frequncy multiplier Oct 14 Frequency doubler & FF make phase shifter 8 traces scope display Clip-on monitor displays count Interruption in power surces (Q=CV) Nov 11 High quality filters(theory & pratice) Ele76 Standard oscillators calibration with color TV(May71 10,Mar75 20,) Direct reading ohmmeter linear Nov 25 Errors in calculators Telephone ring detector without relay (interface) Timer extends life of teletypewriter Assure oscillator start(2 to 5MHz,7404,chokes,Xtals) Kilowatts broadband matching trafos (transmission line) Logic probe displays four modes (74C221,74C02) 555 drives fuel pump SR56 in filter design Dec 9 Regulator extends battery life High gain low Q multiple FB filter Ele76 Up/down latching sequencer energizer(7473,7408,7406) Gate current from data sheet JFETs (Igss) Relay actuating with charged capacitors saves power

ELECTRONICS 77

Jan 6 J-K FF to edge triggered set reset Majority vote multiplexer circuit Single step logic for microprocessor Keyboard scan with I/O ports Current trafo overload-proof Cassete interface (8251) DMM 4 3/4 has dual output (BCD & 7 segments,AY-3-3550) Jan 20 Fast start gated oscillator (4011) Nonoverlapping 2 phase clock Composite video generator (CRT) Input capacitance FB neutralization (2 OPAMP,for high impedance sources) Ele77 HP25 Networks transfer functions Feb 3 Switched & linear power supplies ,voltage references(TL497,MC3420...) Shift registers interface (74165,3 pairs lines) 50% duty cycle TTL clock Memory backup 2.4V battery Reading BCD with only 3 lines (I/O) HP25 Fourier analysis of scope waveforms (errata May 12 Ele77) Feb 17 Pulse height discriminator (2 555) Gain control with analog switch (AMP,FET or CMOS) Instantaneous power in resistors Mar 3 HP signature analysis Precision voltage calibrator pulse divider(4017,4001,.1%) SCR motor crowbar with indutive kick (DC motor stop) Regulator foldback current limiting Ele77Dual OPAMP tempco stabilization (739,749,one heats) Logic tester (7 segments) LED drivers chart (TTL) SR52 plots functions Mar 17 Linear VCA (CA3080) or AGC (741 + transistor) 555 musical envelopes (synthesizers) Note on May 26:10microF omitted Keyboard scan (4067,4042,4029) Cross assembler link TTL drives twisted-pair lines SR52 AWG wire tables Mar 31 Saturable core trafos harden latch memories PROM mode effects binary to BCD converter AGC has 60dB range (741,FET) Ele77MOS OPAMP form pink noise source ( 2 3130) Roving display checks I/O SR56 deals with dBs Apr 14 High Q filter with frequency controlled gate Multiphase clock with decoders & FF Noise filter switches time constants Diagnose auto voltage regulator (4 3900) Measure photodiode resistence at zero bias Apr 28 S/H & OPAMP form special differentiator (AD582,741) FET pair & OPAMP linearize voltage controlled resistor SCR relaxation oscillators Logic functions with multiplexers Coil winding program HP25 May 12 Automatic clamp for symmetrical wave-form offsets Ele77BiFET improves absolute value AMP(3140,1MHz)rectifier 555 freezes meter display Sweep source reduces FM SR52 finds complex determinant ( network matrix) May 26 Interrupts by multiplexers Costas PLL detects differencial PSK modulation(CA3089) Thermometer diode quad OPAMP(LM324) Capacitance meter (2 555 & counter) Low threshold detector(LM311) Jun 9 PLL & S/H control oscillator(4046,555,3900,4016) Majority vote logic First of two inputs (74S02,74LS14) Ele77Interface multiplexer for D/A converters Jun 23 Design of a DVM (3 1/2,Fluke) CMOS PWM (4007) Comparators replace set-point meters OPAMP extends 555 timer range Transistor temperature sensors (theory & circuits) Pulsed source energizes solenoids & relays Pulses check LED Jul 7 SS programable pulse width Resistor controlled LC network drives discriminator Fail safe reset initializes micro UP25 system noise figure Jul 21 Nonmaskable interrupt saves registers Ele77Ratio of two analog signals(digital V/F,S/H) Synchronous SS Gyrators filters Time shared DVM displays D/A converters controls power source Aug 4 Fast attack detector in ultrasonic receiver AM detector with biased diode Maximum voltage detector of a set of inputs 8 traces scope display FIFO buffers (interrupts) Aug 18 Priority encoder Ring counter generator for sine waves Car & trailer ligths link Resistors self-heating (charts) Ele77256 states indication with only two LEDs (16 LEDs,74154,74157) PCB checklist Sep 1 Capacitive transducers measurement with 555 (VCO,F/V) Resistor controlled selector CB channel synthesis (256 channels) Double-ended clamp (quad AMP & 4052) 4004 processor extended inputs (multiplexer) Counter with preAMP(30MHz, FET,ICM7208) S/H bias current network(NF510,LM307) Sep 15 555 overvoltage protector(low too) SCR & relay electronic fuse Phase detector unambiguous(360,74123) Condutivity meter (quad OPAMP) Ele77Check PLL loop sensitivity with a counter DC power supplies in parallel Sep 29 A/D converter improved by buffer(AD7550,microV levels) Timer & converter generate slow ramp Tolerance of capacitors with a MV SR52 in second order differencial equations Nov 10 Random number sequence generator (pseudorandom) Optocoupler tranmits pulse width Data converter drift (theory A/D & D/A) Go/no-go tester for OPAMP Single sweep for scope (74121,7476,Z axis modulation) LED linear range extended by shunt diode(modulation) Nov 24 Digital limiter for telephone line 555 time wiper delay Ele77Calculator in cascaded tuned circuits (HP67) part 1 LED scope display (10 by 10 matrix) Oscillator reacts to magnetic flux (8 to 14 KHz for +-.4 Oersted) Dec 8 Tape recorder for low frequency (modulation XR2208) D/A conversion Calculator in cascaded tuned circuits(HP67) Part 2 Karnaugh map logic analyzer HP25 antenna best angle Dec 22 CMOS metal detector FM demodulator(CA3089 & CA3189) Keyboard programs OPAMP gain Extending linear scale ohmmeter (Up to 500Mohms) 7 segments generator displays PROM on a scope

ELECTRONICS 78

Jan 5 Wind-chill index display (weather data) RAM & D/A wave generator Diode digital thermometer (MC14433,.1C) SR52 scales data for drawing Jan 19 TENS pulse generators Split current source damps reative load oscillations Half-integer divider (4030,4013)(N-1/2) DC/DC power supply down to 1V (switcher,12V,1A,LM311) Differential optical coupler linear (Theory & pratice) Counter & scope for precision Strip line with HP67 Ele78 100% duty cycle out of a 555 Feb 2 Priority encoder Switching multiplier(.05%,4016,741,308,PWM) Liquid nitrogen level(diode sensor) Dynamic range of log AMP Calculator in transmission line (SR56) Feb 16 Nonuniform data-channel sampling PLL filters most inputs (4046,8038) Modulators compensate tape recorder errors (dual channel pilot) Scanner tests diode matrix Mar 2 Module (AD433J/B) linearizes transducers Reference power supply (REF-01) Interfacing a DVM to a micro(F8),(LD131/130) Ele78 Waveform integrator averages over variable elapsed times Mar 16 Scanned keyboard activates 8 tones generator Frequency multiplier uses combinational logic (SqW,up to four times) Semiconductors in nuclear environment Ultrasonic receiver gray tone display High speed digital servo stabilizer Divider by N generates SqW for odd N Mar 30 Sweep ratio extender by capacitance multiplier Synthesizer interpolator extends number of channels SS & counter multiplex pulse width encoders SR52 Cauer filter group delay Apr 13 Diodes & integrator brake small motors PLL: D FF senses lock(565,562) Ele78 SSB : delay lines help generate quadrature voice Two diodes simplify hex-keyboard software Subtractor eliminates OPAMP offset & common-mode errors Apr 27 Ultra fast unity gain buffer AMP (Dual transistor 2N4854) CMOS dual charge flow extend pulse repetition rate(4093,4007,.5microS) PROM bootstrap loader Data acquisition in a chip (ADC0816) Ligth detector checks optical cables(FPT130B,TL074,pulse total energy) Pilot lamp stabilizes crystal oven(LM3911) Tester for solar cell efficiency (OPB730,555) May 11 SR52 : Z transform (sampled data program) May 25 A/D converter with log output(RC discharge clock(74192,555,741,12bits clock(74192,555,741,12bits) Ele78 Switching mode control of DC motors(.01HP,311) Jun 8 Scope calibrator band gap reference In-range frequency detector(MC14528,4013) Cassete data micro interface(74132,4013,7401,4000 bauds) Filter eliminates oscillations in switched converters Mating ECL & TTL families HP25 finds maneuverability Jun 22 Programable frequency multiplier Electronic piano matrix tone generator Double balanced mixer(F1+-F0,4016,HA2520) Three LEDs null detector Jul 6 Built-in delay in alarms(555) Audio noise blanker (radar pulses,ignition) Ele78 4 function calculator times long intervals Jul 20 Ultrasonic pulser(100V to 300V SCR voltage multiplier) Servo up-down ramp Constant voltage & current with two regulators(723) Data pulses to histogram analyser Nyquist plot predicts stability limits (HP25 program) Aug 3 Photodiode radiation monitor(diode,metal.Mylar window,PIN HP,wideband) Auto alarm ,door opening Boosting OPAMP roll-off extends range of filters IHD extending the range of tester(Intermodulation) Aug 17 FM squelch response :tuning meter muting Cascaded FF periodic sequence generator Improve response of phototransistors by bootstrapping(FTP120,6x) Ele78 Crystal time bases(Theory) Aug 31 Width pulse multiplier(digital,external clock) Sep 14 Controller selects mode for multiphase stepping motor Low power transistor curve tracer Digital differentiator determines shaft acceleration(5bits) HP25 SCR conduction angle,power (program) Improving phototransistor pulse response (5microS, IL-CT6) Oct 12 Sine wave from triangle in diode generator(6 segments,<1%) Open collector gate switches RF Frequency multiplier with F/V,D/A,V/F !!!(D/A multiplier) Nov 9 Zero sensing up/down counter reverses in complements (sign too) AMP audio switched supply(parallel output,diode switch) Ele78 Protection of high current power supplies Nov 23 3 phase,zero voltage detector with photoisolators(SCR,etc) Quad OPAMP generator in-quadrature waveforms(SqW & triangle) Logic for step,run & halt commands with one button Self-balancing bridge for thermistor mounts(HP478A power meter Picoampere meter (DVM input impedance) Dec 7 Wien bridge selects notch filter bandwidth Comparator generates pulsed output CMOS gates switch higher than the voltage supply Wire pair multiplexes data & power for display Dec 21 Diodes adapt V/F converter for bipolar signals Prescaler for 135MHz counter Ele78 Recorder time markers from clock module TL59 convolves functions in time domain

ELECTRONICS 79

Jan 4 Filter levels output of Wien oscillators Smoke detector generator for long delays(SD1A) Zero crossing photoisolator for SCR Digital strain gage eliminates A/D converter(555 VCO) CMOS tester for assembly errors Jan 18 CMOS OPAMP offset errors(ICL7600,novel circuit) Control programming with high level languages Circuit phase-locks generators over 360 Unspecified 8085 codes Selectors squeeze data in RAMs Feb 1 Multiplex display Using assembler in high level languages Interface unites micro with calculator (Coprocessor) HP25:Short vertical antennas Feb 15 Touch-tone decoder mates switched filter with digital logic Six-variable logic with multiplexer (74150) HP67:OPAMP gain & CMRR Mar 1 CMOS oscillator with 50% duty cycle FB in phototransistor bandwidth(MRD300,100nanoS,epitaxial) Servo minimizes hunting (DC motors) Measuring OPAMP common mode impedance HP67:track of communications satellites Mar 15 Forth programming Peak detector for narrow pulses(50nanoS,3V,1%,LH0024,1N6263,2N5196) Ele79 Optoisolator initializes signal-averaging circuit(LM6000,Clairex) Timer sawtooth generator(555,30KHz) 8085:8 by 16 product Pseudorandom integers assembler program 5 state LED display monitors paging system Mar 29 Rate multiplier controls noninteger frequency divider(5497,54161) Standby crystal time base backs line clock(Xtal 3.58MHz) Voice pause halts tape playback Linear ICs runs at 1V level(Band gap reference,LM10) DVM has audio output(MC6820) TL59:S coeficients into-port net parameters Apr 12 Analog IC dividers(Theory & pratice,Burr-Brown) Low dropout micropower regulator(LM224,5.2V) Ele79 Missing pulse detector frequency independent Charge pump cuts compandor attack time(NE570,LM324) Serial jobs PROM controller Discriminator computes frequency differential (.1%) 8 channel scanner data multiplexer for chart recorder PLL:Reducing even-order harmonics Apr 26 Call controller Up/down counter data over a single channel(multiplexing) LEDs track signal level (8 by 8 matrix) IEEE-488 bus interface Pulse width range tester HP97:Microwaves couplers response May 10 Bilateral V/C converter CMOS binary to BCD converters Ele79 Power line harmonics measurement with a notch filter(Wien) Resistor trims regulator voltage(+-1%) 8080:32 by 16 bits quotient program May 24 Peak detector for fast pulses(10nanoS,.1 to 1.3V,4%,1435,LF356,FETs) Wideband linear ramp(200V,50KHz,LM0024) Digital peak detector for 4 bits(7485 comparator) Capacitance meter PLL(1%,10pico to 1microF) LED scope with a dot/bar driver 8080 hardware breakpoints (debugging) Jun 7 Pascal programming Parts 1 & 2 Bridged-T filter selects frequency & bandwidth (notch) Pulse generator displays parameters(pulse periode & delay) CMOS triac trigger (OPAMP CA3160,4069) Ele79 Gyrator filter(TCA580 gyrator,TL083) Bipolar V/F converters (Theory & pratice,National LM331,.01%,10KHz) Aug 16 10A peak ammeter (S/H,DVM,.2ohms) Switched current source for I2T Dual color LEDs synthesizes polychromatic ligth Clock tells time out loud (6800) Aug 30 CMOS counter-decoder pair sets divider modulus(74C161,74C154) Shift register white noise generator(4006,4021,4030,25 stages) Instantaneous frequency meter for biomedical use(1/T,AD532 divider) A/D converter(AD7574,8bits) Diode wind-sensor anemometer MC6800 PROM programmer Sep 13 Solar power regulator charges batteries Triac 0 to 360 firing point trigger Ele79 Pattern generator simulates double-density disk data ADC0801:Sampled data converter A/D,charge balancing comparator Cascaded regulators HP67:Antenna polar pattern Sep 27 8 bits bus feeds 16 bits micro Add programmability to a power supply Floppy decoder Using RAMs (static) Micro control of universal motors(triac) Supersensitive measurements(A,V,heat,pressure,friction,charts,Keithley) Ele79 Line distortion telephone tester TL59:FFT program

ELECTRONICS 81

Apr 21 AGC threshold with FET OPAMP Reducing offset in video OPAMP(integrator) Time slot assigner for data examination Reading a dual trace scope with +-.025(S/H,5 1/2 digits DVM,LM398) 6909 debugging program May 5 LM392 AMP & comparator has many uses(sampler,filter fast acquisition, RTD sensor 0 to 500C,1%) Auto alarm Measuring impedances ratiometrically TRS80 :Load cassete data twice as fast May 19 Encoder pulse FB multiplier (digital,74379,74159) Power fail detector (micro) Ele81 Subroutine tests RAM (nondestrutive) HP41:Pseudorandom sequence Counter timer resolves 1microS Jun 2 FM receiver (MC3359) Deglitcher-delay serves as pulse generator AGC in voice-operated mike Linearizing thermistors with a single resistor Sine oscillator multiple phased(without nonlinear components) SS timing error LED indicator(ECL,10231) PWM analog signal isolation(current reference balancing,60Hz clock) Jun 16 Shaft encoder data (4077,4029) Positive regulator works with negative supplies(LM396) Ele81 Dual tones advance slides Light pen generates pltter signals Basic:LC ressonance program Jun 30 FSK transmitter uses two gated oscillator Micro sound generator Upgrade MOS performance Relocable code for 8 bits micro