Circuits for the Hobbyist by VA3AVR

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Active Power Zener Active Antenna for AM-FM-SW  R1/C2 Active Antenna for HF-VHF-UHF Active Antenna, easy to build Active FM Antenna Amplifier Alternating On-Off Switch, #1  Alternating On-Off Switch, #2  Amperage Booster for 78xx's Aviation Band Receiver PCB for Dan Fink's Anemometer (0 available!) Audio Booster with 1 Transistor  Audio Pre-Amplifier #1 Automatic 9-Volt NiCad Battery Charger Auto-Fan, temperature control   AT-121 (3W) to AT-150 (2W) Converter  Basic IC MonoStable Multivibrator Basic RF Oscillator #1 Basic LM3909 Led Flasher Battery Monitor for 12V Lead-Acid Battery Tester for 1.5 & 9V Battery (NiCad) Rejuvenator Bench Top Power Supply, Part 1  Bench Top Power Supply, Part 2  Bench Top Power Supply, Part 3 Bench Top Power Supply, Part 4 Pics   Bench Top Power Supply  Copyright Theft Bench Top Power Supply, Auto-Fan Precison Power Supply, 0-40V/2A  Birdie Doorbell Ringer Broadcast-Band RF Amplifier Bug Detector with Beep Bug Detector Car Back-up Alarm Car Converter for 12V to 9V Car NiCad Charger Christmas Lights Tester Coin Tosser Compressor-Mate Clock Generator Constant Current Charger Continuity Tester, Low-Voltage Continuity Tester, Smart Countersurveillance Monitor Crow Bar #1 Crow Bar #2 Crystal Radio--make your own  Crystal Tester, #1  Crystal Tester, #2 Crystal Tester, #3 Cut Phone Line Detector CW/SSB Radio Add-on SOON Dark/Light Activated Relay DCS 400 Multipurpose Connector DSL Filter (phone-line) Dual 12V Power Supply Egg Timer Electronic Canary (Doorbell) Fish Caller Fluid-Level Detector Fox & Hound, wire tracer Gel Cell Charger, I Gel Cell Charger, II Glowplug Driver (a) Glowplug Panel (b) Headlight Alarm Heat Sensor High-Voltage Projects you can Build  Hot Wire Foam Cutter, 9 - by D.J.Kammo (pterodactylus) Hot-Wire Foam Cutter, 10 - by Tony van Roon Lantern Flasher/Dimmer Latching Continuity Tester  PCB/Layout, 7-20-2010 Lead Acid Battery Charger with Float Lead Acid Battery Charger Lead Acid Charger (Gel Cell) Lead Acid Battery Charger (LM317) Led Flasher, 2 transistor Leds Flasher, alternately Led Strobe Flasher LED Pilot Light (AC or DC) Light Sensor With Hysteresis Lithium-Ion Charger, Single cell Logic Probe(1), with pulse, TTL/CMOS Logic Probe(2), with pulse, TTL/CMOS Logic Probe(3), Audible, TTL/CMOS Main Fuse-Panel Emergency Light Micro-Spy with FET's Micro-Spy with USW Micro-Spy with TTL Miniature FM Transmitter #1 Miniature FM Transmitter #2 Miniature FM Transmitter #3 Miniature FM Transmitter #4 Miniature FM Transmitter #5 Miniature FM Transmitter #6 Miniature FM Transmitter #7 Miniature Tracking Transmitter Mini-Drill variable Powersupply Missing Pulse Detector (Basic)

Morse Code Practice Keyer, I Morse Code Practice Keyer, II Motorcycle Battery Charger Motorcycle Brake Light Flasher Motorcycle Low Voltage Warning Motorcycle Headlight Modulator Regulations  Motorcycle Turn-signal System  No-Hassle 3rd Brakelight hookup Police Siren Practical, 2-wire Intercom Pulse Timer, 555 Pulse Width modulator, NE555 Pulse Width modulator, CD4093 Pulse Width modulator, LM324 Red Alert Alarm, #1 Red Alert Alarm, #2 Relays - Sound Activated, #1 Relays - Sound Activated, #2 Relays - Transistor Boosted Relays - Dark Activated Relays - Delayed Turn-on Relays - Automatic Turn-off Relays - Long Duration Relays - 12 Sec to 90 min Relays - Long Duration--1 to 100 min Relays - Long Duration--1 min to 20 hrs Relays - Self Latching RF Transmitter, light sensing Subcarrier Adapter Listen to those hidden FM transmissions ScanMate Your (Radio) scanner buddy Servo Modification - For contineous rotation Simplest R/C Circuit Simplest RF Transmitter Simple Transistor Audio PreAmplifier Single IC Audio Preamplifier Single Cell Sealed Lead Acid Charger - by Søren  Solar Cell NiCad Charger Solar Panel Sun Tracker Solid State Relay Telephone Transmitter (FM)  Theremin Temperature Controled Fan Temperature Indicator Thermo Alarm Thermostat, #2 Thermostat, #3 (NTC) Thermostat, #4 (1N4148) Third Brake Light Pulser Touch Activated Alarm System Touch Switch using Transistors Two-Tone Trainhorn  Universal Flasher Circuit Universal Lab. Power Supply, Part 1 [2010] "5V/3A, 50V/5A" Universal Lab. Power Supply, Part 2 [2010] "5V/3A, 50V/5A" Variable Power Supply, 1 - 30V @ 1.5A  Wailing Alarm Warble Alarm Whooper Alarm, #1 Whooper Alarm, #2 Water-level Sensing and Control Waterpump Safety Guard for Fish-pond Weller WLC100 Soldering Station Wireless Microphone Xmas Lights Tester Zap Adapter 1.5V Tracking Transmitter 2 Transistor 2 LED Flasher 4 Transistor Tracking Transmitter 4 Transistor Transmitter 7.2V Field Charger (.pdf file) 8A Regulated Power Supply for 13.8V 9-V Stabilized Powersupply 9 to 9 pin (Female) Nullmodem Cable 12V to 9V with a LM317  30-Meter QRP Transmitter for Morse Code 555 DC-AC Inverter 555 Timer IC Tester 555 Go No/Go Tester More advanced Electronic Symbols Template Hobby Kits for your building pleasure Relays High-Voltage Projects you can Build 555 Timer/Oscillator 741 Op-Amp Capacitors Light Emitting Diodes  Diodes & Diodes Data  Photosensitive Devices  7-Segment Displays  Coils Crystal Oscillators (SOON) MosFet Test PLL  Resistor Color Code Tutorial Relays, Relay Drivers, Solid-State SCR Tester Toroids Transistor Tutorial, 12 parts! Triac Test UJT Test

Just in case you're gonna ask: All drawings are created with Paint Shop Pro


Circuits Archive - Older circuits. Most are working, some are not. Could be still useful.
Tony's Data Sheets - Data Sheet for common Semiconductors.
Radio Shack Partnumbers - Most common order numbers for my circuits.
Resistor Value Calculator - By Danny Goodman, AE9F.
TUP/TUN/DUS/DUG European transistor replacement system.
PN100/200 - Data Sheets for the PN100 and PN200.
LF13741 - Monolitic JFET Input OpAmp Data Sheet.
MC14069UB - CMOS Hex Inverter Data Sheet.
Toroids, RF/EMI Cores - Variety of commonly used toroids, colors, etc.
Cambridge Amateur Radio Club - CARC Homepage.

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555 Timer/Oscillator  741 Op-Amp  Capacitors  Light Emitting Diodes   Diodes & Diodes Data   Photosensitive Devices   7-Segment Displays   Converting Frequency to Channel #'s  MosFet Test  Phase Locked Loop   Resistor Color Code  SCR Test  Transistor Tutorial, 12 Parts!  Triac Test  UJT Test  Coils  Toroids RF/EMI  Make Your Own Shunts  Relays, Relay Drivers, Solid-State  555 Timer Tester - Test those 555's in your junkbox  555 Go-No/Go Tester - 555 tester, more advanced  7.2Volt Cycler - 7.2V NiCad packs  7.2V Field Charger (.pdf file)  Airtronics AM/FM - Trainer Cord  Automatic Device Locator - Beacon  9-V Nicad Charger - From the Netherlands  Back and Forth Flasher - Forrest Mims III  Battery Backup (1) - For Large Aircraft  Battery Backup (2) - A better type  Battery Cycler - For Rx/Tx NiCads   Car NiCad Charger - Using car battery  Charger - Constant Current Charger  Crashed Plane Locator - Beacon  DCS 400 Multipurpose Connector  Discharger - NiCad discharger  Elevon Mixer - by Malcolm Aldred  Futaba-AM - Trainer Cord  Futaba-FM - Trainer Cord  Futaba to JR - Trainer Cord  Futaba (AM) to Futaba (FM) - Trainer Cord  FlyWire (Deans Ant.) - For Helicopter  Glowplug Driver - Project for your Flightbox (1)  Glowplug Panel - Project for your Flightbox (2)  Hotchek - Hotcheck (.pdf - See note 1)  Hot-Wire Foam Cutter, 10 - by Tony van Roon  IRF-511 FET - TMOS FET Data Sheet

JR-FM - JR Trainer Cord  Lead Acid Charger, 1 - For Gel-Cell Batteries  Lead-Acid Charger, 2 - Battery Charger  Lead-Acid Charger, 3 - Charger with 'Float' Mini-Drill P.S. - Variable speed for your mini-drill Modifying a Servo - Modifying for indefinate rotation  Model Rocket Launcher - Time delayed  Model Rocket Timer - The half-ounce one  Model Rocket Strobe - Xenon Flash Tube  Model Rocket Parachute - Delayed  Model Rocket Altimeter - PIC Based  Model Train Lights - Head Lights for Model Trains  Model Train Horn, 2-tone - Dual Tone  Sound    NiCad Sensor - NiCad Voltage Monitor for Rx  Night Blades - Helicopter night-blades  Noise Trap - For long servo leads  Added schematic  Power Panel - Combine it with the Glowplug Driver  R/C Emergency Locator Alarm - by Jon Fick Code/Description  R/C Pilot  PCB & Layout 11-04-2006  R/C Switch 2 - For driving accessories   R/C Switch 3 - Similar, but with 4001  R/C Timer Switch - Adjustable, 20-80 seconds  R/C Switch 4 - Modified to use Infra-red cameras  R/C Switch 5 - Electric Motor Switch   Receiver Regulator - Rx Down-converter to 5V.  RX-Volt - Dot/Bar Rx Voltmeter.  Simple Charger - With 'Peak-Detect'  Simple Constant Current Source - by John Nooyen  Sequencial Led Flasher  Servo Driver #1  Servo Driver #2  Servo Driver #3  Servo Driver #4  Servo Modification  Servo Modification - For contineous rotation  Solar Charging - NiCad Charger  Tail Nav Light - For Heli or Aircraft  Variable Power Supply - 1 to 30V/1.5A   Wingtip Nav Lights - Like the real thing  ZAP Adapter - Rejuvenate 'dead' NiCads.  Electronic Symbols Template Hobby Kits for your building pleasure Gadgets for Radio Control "Green" means on-line, "Red" means off-line Bookmark this valuable page with 'Ctrl-D'.

Note 1: The "HotCheck" pdf file belongs to Brent's website but it appears to be off-line for a long time. Here is Brent's pdf file for your building pleasure until I can figure out what's up with his website.

Just in case you're gonna ask: All drawings are created with Paint Shop Pro

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 Circuits Archive - Older circuits. Most are working, some are not. Could be still useful
 My Circuits Page - More interesting circuits can be found here.
 Radio Shack Partnumbers - For the most common parts
  Resistor Value Calculator - By Danny Goodman, AE9F
 Data Sheet - Pin-outs for a variety of other components
 TUP/TUN/DUS/DUG - Elektor/Elektuur's Substitute system
 Toroids, RF/EMI Cores - Variety of commonly used toroids, colors, etc.
 LM301A - High Performance OP-AMP
 LM334 - Three Terminal Adjustable Current Source
 LM3914 - Dot/Bar Display Driver Data Sheet
 MC1455 Timer IC - CMOS Timer/Oscillator (CMOS) Data Sheet
 MC14001 - Quad 2-input NOR Data Sheet
 MC14013B - Dual Type D Flip-Flop Data Sheet
 MC3456/MC3556 Timer IC - CMOS Dual Timer/Oscillator Data Sheet
 MC14069UB - CMOS Hex Inverter Data Sheet
 MC14093B Schmitt Trigger - Quad 2-input NAND Schmitt Trigger Data Sheet
 NE555 Timer IC - Timer/Oscillator Data Sheet
 NE556 Timer IC - Dual Timer/Oscillator Data Sheet
 PN100/200 - Data Sheets for the PN100 and PN200
 LF13741 JFet OpAmp - Monolitic JFET Input OpAmp Data Sheet
Other Interesting Links - Links to other interesting and informative Electronics Websites

"Red" ball means LINK is off-line

Bookmark this valuable page with 'Ctrl-D'.