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ELECTRONIC PROJECTS PDF

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Electronics Projects, VoL 1: A compilation of selected construction projects and circuit ideas . professionals—with a valuable source of electronic circuits, which . Electronics. Projects. FOR. DUMmIES‰ by Earl Boysen and Nancy Muir Wiley also publishes its books in a variety of electronic formats. Some content that. Electric Play Dough Project 1: Make Your Play Dough Light Up, Buzz, and Move! (PDF). Make a light that buzzes and moves from modeling compound, a hobby.


Electronic Projects Pdf

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PDF | This Book is written for all the people who love innovation. It is the Controllable Electronic Load Circuit for DC Power Supply ECE Electronic Projects. 1–1 Why choose electronic projects as a general education .. course Web site as PDF documents with password protection. A Compilation of 21 tested Electronic Construction Projects and 71 Circuit Ideas This volume Complete Electronics Self-Teaching Guide with Projects-Honest.

The various circuits described in this book are for volts A,C, Necessary changes in the power: W circuits usually comisting only of resistors, capacitors, diodes or inductors. We define passive circuits as those that do not connect directly to I' battery. AC supply. The duplcxer is a passive circuu, corn-. Similarly, a So, passive circuits vou find ill Ihi, issue do not require ;.

With miniature components and extreme care you can build a low power lamp dimmer right into a socket. Without a heat sinkr I Triac Ql handles up to a ,watt lamp. Instead of a relatively expensive trigger diode. Because the neon does not trip the gate until it conducts, the lamp turns on at medium brilliance.

The lamp can then be backed off to a soft glow. Because the neon. Press push- button switch 52 and the siren starts up, shifting to a higher frequency. Release it and the tone slides down until you send it up again by punching Adjustment of overall tone quality is made by changing C2 to another value. If the siren pulsates before the pushbutton switch is pressed.

Ql is too "leaky. Assemble this accessor, in a metal can. MHz on a RF voltage must not exceed approximately lOOV. Once C2 is adjustecf to the proper beat fr. No antenna is needed if the unit is assembled in a plastic cabinet. You can rnaka accurate voltage measurements with your oscilloscope if you calibrate the vertical input with a Scope Calibrator. When the voltage at the top of the zener goes positive, it builds until it reaches 10 V. At that point the diode conducts.

The result is a square wave which varies from zero to 10 V, as shown. The scope's vertical input is connected across the diode and the vertical attenuator control is adjusted so the square wave exactly fills one vertical division. This provides a calibration of 10 V peak-to-peak per division. The scope's vertical attenuator then provides multiples of the. The output can be run into any microphone.

The circuit serves only to convert high to low impedance; it provides no amplification. A metal enclosure must be used. The Field Effect Transistor. Using FET semiconductors with their high input impedance, this basic mixer can be used with high impedance crystal and ceo ramic microphones. It does not attenuate low frequetiCy response wr. The mixer's response is 10 to. Two mixers can be built into the same cabinet for stereb use. Give it a shot of direct current, and any AC power tool motor will instantly stop.

No more free-running power saws or drills with the Dynamic Brake. The unit must be assembled in a metal enclosure as the enclosure provides the heat sink for silicon rectifier This diode has only one solder terminal, the case is the second terminal. Place a single strip of plastic e.

When the adhesive is dry solder one con-. Polarity is not important; any wire can go to any SRI terminal. Switch SI is a center-off, one side spring return. With SI on, AC will be fed to the motor and the motor will run. The switch returns to the center off position when released. Thus a CW signal that blows your headphones off one moment might lie buried on the threshold of hearing. The Headphone Limiter chops those S signals down to size until they equalize with weaker signals, giving relatively constant headphone vol-.

Because the clipping action produces some distortion, the limiter should feed a headphone Q-peaker described in another circuit. The value of Rx should match the existing speaker impedance and power. A large antenna always beats the small one, so why use a dinky loaded whip for portable work? Make your own coaxial antenna from. Attach the lower end of the cable to your transceiver.

Attach a glass or ceramic insulator to the end of the center conductor and hang the antenna from a tree, roof, pole. Level controls 'In and R2 should not be run wide open with, hi-Z mikes 'since the input impedance then becomes the value of R3 and R4.

Transistor 01 can be almost any general purpose type such as the 2N or 2N However, the better the transistor. Top quality high-gain transistors should not be used since relatively high leakage current of ex-. Transistors with low leakage might produce high distortion because of low "internal" base bias.

Operating on exactly kHz, the Scope eral purpose scopes. If the scope is set, for Calibrator provides a reference for calibrat- example, so one cycle of the signal fills exing the variable time base oscillator of gen- ,actly 10 graticule divisions, each division.

Now if the scope's time base osclllator is sulticiently stable so it doesn't drift too far off, you can make precise measurements of an unknown pulse width, length. Providing an adjustable output voltage up to 35 VDC and maximum output current of mA, this battery charger handles just about any NiCad battery used by expertmenters and consumer equipment. Transistor Ql must be mounted on a heat sink which can be a metal cabinet. Since Ql's case is also the collector connection it must be insulated from the cabinet.

To check fOr opens, first plug the tester into a live outlet. Next, connect the. You are only interested in whether the lamp lights at all-not the level of brilliance. If the lamp lights with either connection there is a short to the frame. If the lamp fails to light at all, the appliance frame is safe. After the repair is made tryout the appliance by using the fused power outlet, PLl.

This way, if the appliance is still defective it will blow fuse F1 rather than a fuse in the basement. Diodes such as the IN34 cannot be checked since test current is too high. If the diode is good, the lamp will light in one direction, and remain dark when the diode is reversed. If the lamp stays on when the diode is reversed, the diode is shorted. If the lamp stays dark when the diode is reversed, the diode is open.

The only re-, checker. It is intended only for silicon rectifiers rated higher than rnA and indicates open and shorted condltions. The lamp must be as specified: Do 'not use a larger lamp or the diode might be destroyed.

Close switch SI to check the lamp by turning it on. Connect the diode both ways, opening SI for the test. One way the lamp should go on; reversing the diode should. If the lamp stays on in both directions, the diode is shorted. If the lamp stays out in both directions the diode is open. YDC tllic c. II, 5 tur. Wind the coil as tightly as possible and stretch it to a length of 1 inch. The shield connects to the transceiver's chassis and to the bottom end of U.

Making Cl smaller narrows the tuning range. An effective speech clipper for transmitters and PA systems can be made from only two diodes and a capacitor. The diodes clip at approximately.

If the preamp uses a negative supply, reverse CI's polarity. The output level to the rest of the amplifier is deterMined by R 1. Use the necessary value between and 10, ohms. Working directly from a minute sample of the transceiver's RF output, the Modulamp will glow only if there is a carrier output and modulation. So if no one replies to your call and the lamp glows in step with your rnodulation, you can at least be certain it's not the transceiver that's at fault.

If the unit is built into a small metal box, jacks J 1 and J2 should match the existing transmission line connectors. If you build the Modulamp directly into your transceiver, simply connect capacitor Cl to the RF output jack and forget about Jl and J2. To adjust, simply talk into the mike in ycur normal voice and adjust trimmer potentiometer R2 until lamp II flashes in step with the modulation.

If 11 will not flash regardless of. R2's adjustment, substitute a hither gain transistor for Ql try a 2N Just about any transistor rated LI--l turns 22 solid, p'astic-insulated wire, adJacent to ground end of L2 L turns 18 enameled wire, centered on form. Critical inspection of 'a transmitter signal and accurate measurement of modulation is possible only with an oscilloscope.

Unfortunately, a CB transmitter's RF output is so. Since a scope's vertical plate connections operate at a high input voltage, it requires that a CB transmitter's output be fed to a resonant circuit to step up to high RF voltage. The circuit shown will just about fill a 5-in. Then wind L1 adjacent to the ground end of L2. Connect II across the transmitter output with the CB antenna system also connected.

If the coil is correctly made, there should be no change in the antenna system's SWR. Note that you must use your scope's vertical plate connection. This monitor "steals" an insignificant amount of power, yet keeps constant watch on a CB rig's RF output. If a failing tube starts to drop the output, the line monitor immediately lets you know if. The device can be built in a separate metal cabinet or customized into the transceiver's cabinet. An alternate, pickup is about 6 ill.

If the shield is broken, solder a heavy copper wire to join the broken ends to avoid messing Lip your antenna's transmission line. Vary the number of turns in the loop to secure approximately half-scale meter indication.

Potentiometer R2 serves as a coarse sensitivity control. QI can be any general purpose pnp transistor of the 2N or 2N variety, though greater sensitivity is obtained with the 2N type. Relay Kl is a high-sensitivity type like the Sigmas used by model radio control hobbyists. Price is important if the results are equal. The gate is tripped by light entering a small lens built into the top cap. To operate, provide a s-tn. Make certain the anode lead connects to the positive sync terminal.

When using the device, bend the connecting wires so the LASeR lens faces the main flash. This will fire the remote unit.

No reset switch is needed. Old universal appliance motors and shadedpole induction motors salvaged from inexpensive turntables can be easily converted to slow-speed hobby drills, chemical stirrers, van-speed turntables movable display drives, etc.

It's done with a full-wave Triac speed controller. Unlike other speed controllers, which reo quire an external trigger device, Q1 cornbines both the Triac and Diac trigger diodes in the same case. Triac Q1 must be provided with a heat sink, which can be the metal cabinet. Build up a merble-stzs mound of epoxy on the cabinet and insert QL's case into the epoxy.

When the epoxy hardens the Triac's heat is dissipated to the cabinet, Make certain Ql's case is not shorted to he cabinet and 'is insulated by the epoxy.

150+ Electronics Projects for Engineering Students

With the component values shown on the parts list, the Triac controls motor speed from full off to fuil on. As Cl discharges through Q2's base. Q2 is turned off. Potentiometer R2 determines the tlip- flop rate. This simple modulation monitor for AM ham transmitters requires no connection to the transmitter. Just position the loop near the final tank or antenna matching coil un-. Transistor Ql functions as an amplifier, but positive feedback from n's secondary to Ql's base- causes the circuit to regenerate.

This produces a steady stream of clicks in the speaker. The rate of oscillation, or number of clicks per minute, is determined by RI's setting.

A calibration point for "one click per second" can be marked on the dial for photo exposure control. If the generator does not click when power is first applied, interchange the two leads from n's secondary. Do not interchange the speaker leads!

Small enough to fit into a Cigarette pack, this pocket pager produces a low-output Signal on the Citizen's Band 27 MHz suitable for pag"lg inside a building. The signal is strong enough to be heard on a standard. If only one crystal frequency is peeded, socket can be eliminated and an overtone type crystal soldered directly into the circuit. Salvage crystals from junked units, The whip ante"nna is a standard walkietalkie three-section replacement type.

The carbon microphone can be a telephone. To tune; receive the signal on an S-meterequipped receiver and adjust trimmer C3 for maximum output. Key the transmitter a few times to check crystal activity. If starting is intermittent, slightly alter C3's adjustment until operation is consistent. We don't suggest that you start aligning your stereo FM receiver, but some budgetpriced and early-model FM mono receivers can be- aligned or peaked with the FM Alignment Oscillator.

Using a 7V mercury battery, the oscillator provides a radiated signal within 10 feet of the receiver. It's strong enough for alignment purposes, but won't overload the front end. The 4-turn section is tight-wound, no spacing between turns. The tap is made by scraping off some enamel, tinning the bare area, then soldering a solid bare wire to the tap. Frequency is preset by adjusting C4. Can't find that rare, weak SW signal from lower Siobbovia?

You will if you use this SW frequency spotter. Obtain crystals on or near your favorite SW stations, plug 'em into the spotter and you'll transmit powerhouse markers on the shortwave bands. With no BFO, simply tune around the frequency until the receiver gets deathly quiet. Either way, you'll talibrate your reo ceiver with great accuracy.

The spotter can be assembled on a srnalt section of perfboard with flea clips for tie points. For good performance, ail components must be firmly mounted and well. Crystals in this circuit are fundamental type, not overtone. FC-l-mH RF ch A connection between the spotter and reo ceiver is not needed.

Simply position the spotter near the receiver antenna and start tuning until you find the marker signal. You can always feed an audio generator into a mike input to check an AF system, but how do you check the mike? Saying "woof, woof, hello, test" gets mighty tiring.

Instead, clamp the Mike Beeper to the front of the mike with a rubber band and you'll. The beeper can be built in a small plastic case-nothing is critical. The speaker may be any size from one to three inches.

Triac Q1 is supplied with a heat sink which must, in turn, be connected to a larger heat sink. The entire unit is assembled in a metal cabinet with Q1'sheat sink epoxy-cemented. Connect an SAG fast-action 5. In this circuit 3AG fuses c' be used.

+ Electronics Projects for Engineering Students

Potentiometer R2 will ' Just the lamp's intensity from full t'J. Don't radio uses transistor Q1 as a diode detec- intermix them since! Detection is age can destroy a tra "stor. F, lO. Approximately 10 dB of extra micriphone amplification for CB and ham transmitters, tape recorders and PA amplifiers is provided by the field effect transistor. Since an FET's input is many megohms, the arnplifier's input impedance is determined by gate resistor Rl.

It's a suitable load for high impedance crystal and ceramic microphones. The amplifier is "flat" from 20 to 20, Hz. Low frequency response can be attenuate: R2's leads as short as possible.

As you key the transmitter, set switch SI to calibrate and adjust R2 for a fu! Better accuracy is assured if R2's adjustment and meter calibrating point is compared against a scope modulation pattern. Don't compare this meter against comrnercial CB modulation meters. On a tone signal, this one is less accurate, but on speech modulation, the commercial models are not as accurate as a circuit of this type. Power supply by-pass capacitor C4 must be used regardless of whether the voltage supply is a rectifier or battery.

If C4 is not used there might be severe low frequency attenuation, sharply reduced gain or instability. Tuning range is from 1. The coil can use phone tip jacks for a plug-in connection for band changing. Consult any coil table for U's winding data since coil. Even greater sensitivity is obtained if a more sensitive meter is used. Resistor Rx is the load resistor f"lr the amplifier; 4, 8 or 16 ohms at the appropriate power rating.

The AC meter can be an A '. Adjust the amplifier for the desired power output, set switch SI to the caiibrate position and note the meter reading. What's left is the-harmonic content. Add that 'way-out fuzz sound to any electric guitar by connecting the Fuzzbox qetween your guitar and amplifier.

Potentlcmeter R3 sets the degree of fuzz. RR the output level. Since the fuzz effect cannot be completely eliminated by R3. The switch should completely disconnect the fuzzbox output; the input can remain in parallel with the bypass switch. The Nixie-actually a peanut-size tubehas 10 numerical-shaped neon lamps 0 through 9.

By shorting the appropriate lead to ground. Transformer Tl is V center-tapped,. Though current requirements are very-low, 01 and 02 should be llne-voltage type silicon rectifiers of mA minimum. The neon numbers can be turned on either through an Ll-pcsition one position for off rotary switch or individual toggle switches. Fuzz, echo, reverb, big bass. They're all out! The new guitar sound is funky, and you'll get with it with the wide- range Funk Box.

Just crank potentiometer R7 and you'll get an extra twang from way. Just about any construction can be used.. If you build it in a metal box, use a push switch for switch 51 and you'll be able to key the effect in and out with your foot. To adjust the Funk Box Simply adjust potentiometer R4 until you hear a whistle oscillation ; then back off R4 until the oscillation just ceases.

Connect your guitar to jack J 1 and twang away. The effect can be varied from bass to treble by adjusting potentiometer R7. Using diode switching, a single pair of wires controls two circuits that normally require four wires. Though illustrated here with.

Lamp 12 remains off because diode 02 blocks the flow of DC to. If a carbon mike is connected in series with the battery and the lamps are replaced with headphones, switch 51 determines which of two headphones receives the transmitted signal. If the VTVM indio cates 0. The circuit under test connects to. To avoid damage always start with 51 in the XI position and downrange until the VTVM indicates a convenient reading.

Here's a self- powered CW keying monitor that doesn't require a direct connection to the transmitter or transmission line. Sirnply position coil, Ll near the transmitter output tank until you obtain a dependable key-down tone.

Then tape the coil in position. While the signal is generally monttared with headphones, a small monitor amplifier can be used. If the signal pickup is not sufficient to produce a steady tone, mcrease the coil one turn at a time until the tone is steady and reliable. If you cannot obtain any sort of tone with any coil, reo verse the primary transformer connections A and B.

LI-2 to 6 turns on '1,. Just a handful of parts is all it takes to add up to 30 db gain for lew-impedance microphone inputs found on tape recorders, CB rigs, etc. Because transistor Q1 is a high-gain type it is very sensitive to slight changes in base bias. Hence, bias resistor Rx must be tail: Temporarily connect a 2 megohm potentiometer in place of Rx and adjust the pot until the collector.

Quite often the audio output from small projects is just barely sufficient to produce a recognizable signal in standard experimenter magnetic earphones.

Yet a handful of surplus components will provide enough gain to turn that whisper sound into a roar. Specifically intended for use with magnetic earphones of from to ohms impedance, the Headphone Amplifier can do double-duty as an audio signal tracer. Transistor Ql can be. Even the for-a-buck kind will work.

Volume control R1 should have an audio taper. Make certain C2's polarity is correct; the positive terrnlnal connects to volume control Rl wiper terminal , Adjust distortion control R3 for best sound quality.

If you use a jack and plug to connect your headphones to this' amp, you can eliminate on-off switch S1 because power is removed whenever the headphones are, disconnected. A fast way to see if the crystal from your transmitter or receiver is properly "active" is to compare its output against that of a.

This crystal checker will handle both fundamental and overtone type crystals. Socket should match the pins on your crystals. If you use more t"one type of crystal, install two or. The unit can bitassembled in any type of cabinet. Then install the questionable crystal,.

PB1 and note its meter reading; if it's IDOd its output should approxlmate that of tha reference crystal. Take care that you do! If good crystaTSc drive the meter off scale, install a ohm, 1fz watt, 10 percent resistor in series with meter M 1. And if you can't scrounge the lamps, they're available at just about every radio parts distributor and service shop. Switch Sl is needed only to bypass the squelch for very weak signals. In many instances, the circuit will provide a basic attenuation of the noise back-.

But it's: Just about any enclosure, plastic or metal, can be used. The components can even lie on the table. Flag for inappropriate content. Related titles. Electronics Projects No. Popular Electronics Electronic Hobbyists Handbook Jump to Page. Search inside document. The duplcxer is a passive circuu, corn- posed entirety of resistive, capacitive and inductive dements, That electrically permits tbe.

Re move the 4 - scale cover from meIer M 1 a nd borrow an f"C va ri able auto! Though there is a Iways a signal level loss through a pad, the circuit shown provides the absolute minimum loss that: With few exceptions, modern solid -state am pllfiers have output transformer and a utornatically match a ny speaker irnpeda nee between 4 and 16 ohms. II your speakers are 4 ohms, and you plan to use 4 ohm remote speakers use the circuit modification shown, Switching in the remote speaker will result in the main and remote speakers 6 being series connected for a total load of 8 ohms.

MAIN , 4n 52b. R2, R This unit should be built in a metal enclosure. II the load is watts use an autotransformer rated at least ;"'atts: Simply pi ug a tube into the match ing socket if the filament is okay, lamp 11 will light It you have any oddball tu bes that use sockets other tha n the standard three shown, sim plybu ild them inlo Ihe checker. I"mp SOl-Octal. RF Filter C: UEI er, c. ItO VDC F III,e e. Adjust the volume on t he receive for a h iglo, und istorted transmission by the rebrcadcaster D Motel Alarm Here's security for the traveller.

Just con nect this alarm to the doorknob of your motel room and a loud buzzer will sound if anyone touches the doorknob. Cl pF' ,n RF coli D Professional Burglar Alarm' This professional type burglar alarm can be used to protect windows or glass a reas by. All protective door and window 16 circuits must be normally closed and series connected so that an open i ng of any protective device will trigger the alarm.

The recommended power supply -6V N. Dl, D2-SlIlcon rec: Brumfield EP-'2JO nected to haildle,thei i'!! I-"De c. Cl0 ,L! YDe upocltn LI-s While an pnp transistor is shown, an npn 'type can be substituted if the battery and C I 's polarity are reversed. Ql is a common base amplifier providing a low impedance input to match a low irn- pedance speaker of 3. The microphone can be a surplus carbon type or telepbne transmitter element.

The entire unit can be assembled inside a speaker-trumpet if care is taken to acousti- "m;: Ikolin" celli II. MIC-Carbcn microphone Mo'orol.. H EI'. S-Y batteev Cl-G.

That is, C2 should always be about 10 times larger m Fish, Caller Click-click might no: SOli YDC ,ilver mica c: Millu PI-Insulated 5-way bindin9 pa. Battery current drain is only about 1 milliampere, h it the hooks, For proper operation Tl must be subrniniature type about half as large as your thumb.

Electronics Projects Vol 26

YDC ",. Ilh a I'll' 25 sister On its highest output impedance, pre ferably 16 ohms. Darken tile room lights, open the camera shutter and break a lamp bulb with a hammer. The sound of the hammer striking the lamp will trigger t he flash, a nd the picture will have been taken at that instant: Check incorrect pnasing by making certain the me- 26 ter leads a re connected 10 the amplifier "hot" terminals.

Y batt. But a stereo recorder can automate the whole show so slides change automatically in step with the commentary, Record your commentary on the left track, At the instant you want slides to change, record a one-second noise or tone burst on the right track, Connect the programmer between the reeo rder' s right speaker ou tput and the projector's remote control cable Make a test run to determine the right-track volume setting to make noise or tone bursts activate relay Kl.

ED Enlarger Meter Every print a good print! That's what you get with the Enlarger Meter. The larger the value for C2 and C3, the better the filtering. Supply for SSProjects Though the t ra ns former is n't center-fa pped in this circuit, the bridge rectifier provides 30 tull-wave rectification with an easy-to-fitter DC out pu Lit forms 11 ha ndy supply for solid- state projects. Silicon rectifiers D 1 th rough D4 must have The output voltage is equal to tile secon- a PIV rating equal to at lea st the DC output dary voltage multiplied by Or, working voltage.

OIl'PII' voltag" er, ZOO-PlY ,;". I d'olytic ClIp. For example, you can use a 9. The power rating for the zener diode is de- ' terrnined by the voltage across the diode squared, divided by diode's nominal interna I resistance You can calcu late the inter- nal resistance by worki ng backwa rds from the zeners power rating.

The lamp maintains constant charging of appr oxi mately 20 mA th rough one to tou r 1.

Where is it used? Standard Few shortwave receivers below' the deluxe class have really accurate dial calibration. It's the cheapest route to grea terselettivily. Vl, , S-Y All. Ma ke certai n the ends of the an tenna are i nsulated with glass or cerarn ic insu lators, scale. YDC y pa. RS-5DI M. You'II know you left the Headlight Minder lets you knqw.

Iectrolytlc c. Super sensitivity is the feature of this twotransistor shortwave preselector. It provides ' Ql must be harodled with a shcrt-clrcuit across all leads until just before power is applied, Also.

ER When As the speed of an electric drill is decrel'sed by loading, its torque also drops. So the first impulse opens Kl's con- tIet. To prevent ambient lilht from trippin, the VAC- photocell, it shoull! PIY sllic. AlIS lotchl. SI-Spst switch N. When the top of zener diode 01 goes negative it conducts and voltage across the di- 'A. The mixer's response is 10 to 2O,OOO1iertz. The Headphone Limiter chops those S signals down to size until they equalize with weaker signals, giving relatively constant headphone vol- ume.

Make your own coaxial antenna from a length of RGU coaxial cable. Cut away the outer insulation for l08 inches and fold the shield braid back along 47 or window. Top quality high-gain transistors should not be used since relatively high leakage current of ex- I! HII per peteM. If the scope is set, for Calibrator provides a reference for calibrat- example, so one cycle of the signal fills exing the variable time base oscillator of gen- ,actly 10 graticule divisions, each division 4!

Now if the scope's time base osclllator is sulticiently stable so it doesn't drift too far off, you can make precise measurements of an unknown pulse width, length and frequency. I Providing an adjustable output voltage up to 35 VDC and maximum output current of mA, this battery charger handles just about any NiCad battery used by expertmenters and consumer equipment.

If you suspect there is a short from the appliance's motor or heating coil to the appli- ance frame which can cause a shock hazard, connect one test lead to the appliance frame and connect the other test lead first to one prong of the appliance's plug and then to the other prong. One way the lamp should go on; reversing the diode should cause the lamp to extinguish.

E Speech Snipper An effective speech clipper for transmitters and PA systems can be made from only two diodes and a capacitor. If 11 will not flash regardless of PA. RF sluC. Ml-t-1 mA DC m. Remove a part of the shield at: Ell Candle Power Control Wi.

J this photo relay turns a light on or off ac- , cording general room illumination. Or use a ftashlilht to trip Kl for "kill- inc" TV commerelals by shortinc the TV speaker connections.

I-uF, YDC capacit.

The motor used for the load must be lirn- ited to 6 amperes maximum or watts. L current through Q2 and lamp' L1 lights. Cl-l ll-VDC eI. In Modulation Monitor 01 This simple modulation monitor for AM ham transmitters requires no connection to the transmitter.

With a little time and patience, a dial affixed to Rl '5 shaft can be calibrated in "beats CI. The signal is strong enough to be heard on a standard.. The carbon microphone can be a telephone transmitter, To tune; receive the signal on an S-meterequipped receiver and adjust trimmer C3 for maximum output.

For good performance, ail components must be firmly mounted and well 57 ,. Instead, clamp the Mike Beeper to the front of the mike with a rubber band and you'll send continuous tone through the mike. The entire unit is assembled in a metal cabinet with Q1'sheat sink epoxy-cemented to the cabinet for heat d1SSipatioi1.

Tuning capacitor C1 is a mill; ,uri I'. R3 CAL. M CI, C2-O. Jl, J2-'ho.. Sia o the minimum reading divided by the canbrate reading x OX The same power supply can be used for additional Nixies, each connecting to the top of Cl.

F Myl. OS uF Myl. F MyI. PlY 1 A silico. Lamp 12 remains off because diode 02 blocks the flow of DC to the lamp. When battery polarity is reversed, so the top wire is negative, only 02 conducts, il- luminating The circuit under test connects to PA. J CI-O. For those people, the below list of electronics projects ideas would be more helpful. We have collected best electronics projects list from various resources and listed them below in a tabular form. You may get best idea by reading all these project ideas and if you are interested, you may give few suggestions, comments, new electronics projects ideas also.

Plz give me new project idea for my…. I really appreciate your contribution to making we engineers realise who we are because your tutorials are very useful and easy to understand…. Thanks very much.. As we are in final year. Lovely circuits…. Iam electronic and communication engineering student. I am much into circuit project.

Thus I will definitely choose radio circuit project. Anyway, thanks for sharing this information. Your email address will not be published. You are here: Comments Pls can u mail me the synopsis of rf controlled hovercraft.

GIUSEPPINA from Vermont
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