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
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
DC Motor Reversing Circuit
DC Motor Control Circuit
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 
HotChek – Brent’s website
Hot Wire Foam Cutter, 1 – by Tom Weedom
Hot Wire Foam Cutter, 2 – by Charles Wenzel
Hot Wire Foam Cutter, 3 – by Steven Mohr
Hot Wire Foam Cutter, 4 – by JoeBoy
Hot Wire Foam Cutter, 5 – by The Hermit MachineShop
Hot Wire Foam Cutter, 6 – by Al Schoepp
Hot Wire Foam Cutter, 7 – by Rocket Team Vatsaas
Hot Wire Foam Cutter, 8 – by Daniel Hartman
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
Morse Code Practice Keyer, III
Motor Accu Lader  (Dutch language)
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
Power Supply Converted from a PC – by Andy Batts
Practical, 2-wire Intercom
Pulse Timer, 555
Pulse Width modulator, NE555
Pulse Width modulator, CD4093
Pulse Width modulator, LM324
Radio Shack Special – Transmitters by Patrick Cambre
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
Simple Solar Regulator
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 Cell Regulator
A simple solar panel regulator
Solar Panel Sun Tracker
Solid State Relay
Telephone Transmitter (FM)
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
Light Emitting Diodes
Diodes & Diodes Data
Photosensitive Devices
 7-Segment Displays
Crystal Oscillators (SOON)
MosFet Test
Piezo Education/Tutorial
Resistor Color Code Tutorial
Relays, Relay Drivers, Solid-State
SCR Tester
Transistor Tutorial, 12 parts!
Triac Test
UJT Test


Power Jack 3500Watt Inverter – The nightmare for customers done by incompetent Taiwan “engineers”. Buyers beware!
Stefan’s Electronic Projects – Projects and Repairs for Hobbyists, Experimenters, and Aviators.
Testing the Sanyo Eneloop NiMH’s – by Stefan Vorkoetter
Circuits Archive – Older circuits. Most are working, some are not. Could be still useful.
Tony’s Data Sheets – Data Sheet for common Semiconductors.
Data Sheets Archive – Link to tons of data sheets.
Filter Solutions – PC windows based filter synthesis and analysis software.
RP Electronics – Panel Meters, Analog/LCD.
Radio Shack Partnumbers – Most common order numbers for my circuits.
Resistor Value Calculator – By Danny Goodman, AE9F.
Transistor ‘SM’ marking codes by Philips Corp.
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.
Other Interesting Links – Links to other interesting and informative Electronics Websites



 555 Timer/Oscillator
 741 Op-Amp
 Light Emitting Diodes
 Diodes & Diodes Data
 Photosensitive Devices
 7-Segment Displays
 Converting Frequency to Channel #’s
 MosFet Test
 Piezo Education/Tutorial
 Phase Locked Loop
 Resistor Color Code
 SCR Test
 Transistor Tutorial, 12 Parts!
 Triac Test
 UJT Test
 Toroids RF/EMI
 Make Your Own Shunts
 Relays, Relay Drivers, Solid-State


ne555 555 Timer Tester – Test those 555’s in your junkbox
lm555 555 Go-No/Go Tester – 555 tester, more advanced
7.2V Cycler 7.2Volt Cycler – 7.2V NiCad packs
7.2V pdf 7.2V Field Charger (.pdf file)
Airtr am/fm Airtronics AM/FM – Trainer Cord
adl Automatic Device Locator – Beacon
AutoPilot Auto Pilot for R/C – Commercial device
9V NiCad 9-V Nicad Charger – From the Netherlands
kit Back and Forth Flasher – Forrest Mims III
back large Battery Backup (1) – For Large Aircraft
RX Back Battery Backup (2) – A better type
Cycler Battery Cycler – For Rx/Tx NiCads
BEC BEC Speed Controller – Stefan’s Website
12v Charger Car NiCad Charger – Using car battery
CCharger Charger – Constant Current Charger
Locator Crashed Plane Locator – Beacon
DCS400 DCS 400 Multipurpose Connector
Discharger Discharger – NiCad discharger
mixer Elevon Mixer – by Malcolm Aldred
Futaba AM Futaba-AM – Trainer Cord
Futaba FM Futaba-FM – Trainer Cord
Futaba to JR Futaba to JR – Trainer Cord
Futaba to JR Futaba (AM) to Futaba (FM) – Trainer Cord
Flywire FlyWire (Deans Ant.) – For Helicopter
Glowp driver Glowplug Driver – Project for your Flightbox (1)
Glow panel Glowplug Panel – Project for your Flightbox (2)
HotChek Hotchek – Hotcheck (.pdf – See note 1)
foam cutter1 Hot Wire Foam Cutter, 1 – by Tom Weedom
foam cutter2 Hot Wire Foam Cutter, 2 – by Charles Wenzel
foam cutter3 Hot Wire Foam Cutter, 3 – by Steven Mohr
foam cutter4 Hot Wire Foam Cutter, 4 – by JoeBoy
foam cutter5 Hot Wire Foam Cutter, 5 – by The Hermit MachineShop
foam cutter6 Hot Wire Foam Cutter, 6 – by Al Schoepp  Link
foam cutter7 Hot Wire Foam Cutter, 7 – by Rocket Team Vatsaas
foam cutter8 Hot Wire Foam Cutter, 8 – by Daniel Hartman
foam cutter10 Hot-Wire Foam Cutter, 10 – by Tony van Roon
IRF511 IRF-511 FET – TMOS FET Data Sheet

JRFM JR-FM – JR Trainer Cord
Gell Type Lead Acid Charger, 1 – For Gel-Cell Batteries
LABC Lead-Acid Charger, 2 – Battery Charger
LABC2 Lead-Acid Charger, 3 – Charger with ‘Float’
minidrill Mini-Drill P.S. – Variable speed for your mini-drill
servo Modifying a Servo – Modifying for indefinate rotation
rocket Model Rocket Launcher – Time delayed
launch Model Rocket Launch Controller – Matthew Hewson
timer Model Rocket Timer – The half-ounce one
strobe Model Rocket Strobe – Xenon Flash Tube
parachute Model Rocket Parachute – Delayed
altimeter Model Rocket Altimeter – PIC Based
train Model Train Lights – Head Lights for Model Trains
trainh Model Train Horn, 2-tone – Dual Tone  Sound
rpaisley Model Train Website – Excellent site by R. Paisley
Sensor NiCad Sensor – NiCad Voltage Monitor for Rx
blade Night Blades – Helicopter night-blades
trap Noise Trap – For long servo leads Added schematic
locator PCM/PPM Locator & Voltage Watch – by M.J. Pawlowsky
pp Power Panel – Combine it with the Glowplug Driver
prc Proportional Radio Control
 R/C Digital Camera Controller
 R/C Emergency Locator Alarm – by Jon Fick Code/Description
 More PIC codes and articles – by Jon Fick
 R/C Helicopter Camera
 R/C Pilot  PCB & Layout 11-04-2006
rc-sw R/C Switch 2 – For driving accessories
rc-sw3 R/C Switch 3 – Similar, but with 4001
rc-timer R/C Timer Switch – Adjustable, 20-80 seconds
rc-sw4 R/C Switch 4 – Modified to use Infra-red cameras
rc-sw5 R/C Switch 5 – Electric Motor Switch
7805 Receiver Regulator – Rx Down-converter to 5V.
rx-v RX-Volt – Dot/Bar Rx Voltmeter.
Charger Simple Charger – With ‘Peak-Detect’
current Simple Constant Current Source – by John Nooyen
LFlasher Sequencial Led Flasher
servo11 Servo Driver #1
servo2 Servo Driver #2
servo3 Servo Driver #3
servo4 Servo Driver #4
servo4 Servo Modification
batts Servo Driver/Fuel Mix calculator – by Andy Batts
servo5 Servo Driver using PIC
servo Servo Modification – For contineous rotation
solar Solar Charging – NiCad Charger
toycar Toy Car Tx/Rx 27MHz – plus 49Mhz
stopsig Stop-signal Override for Model Railways
tail Tail Nav Light – For Heli or Aircraft
PS Variable Power Supply – 1 to 30V/1.5A
wing Wingtip Nav Lights – Like the real thing
rejuv ZAP Adapter – Rejuvenate ‘dead’ NiCads.
parts 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.

Other Information and data

archive Circuits Archive – Older circuits. Most are working, some are not. Could be still useful
circuits My Circuits Page – More interesting circuits can be found here.
data Radio Shack Partnumbers – For the most common parts
calc  Resistor Value Calculator – By Danny Goodman, AE9F
data Data Sheet – Pin-outs for a variety of other components
TUP-TUN TUP/TUN/DUS/DUG – Elektor/Elektuur’s Substitute system
toroids Toroids, RF/EMI Cores – Variety of commonly used toroids, colors, etc.
nicads Zapping NiCads/Lithium-Ion batteries – Getting the most from your batteries
LM301A LM301A – High Performance OP-AMP
LM334 LM334 – Three Terminal Adjustable Current Source
LM3914 LM3914 – Dot/Bar Display Driver Data Sheet
MC1455 MC1455 Timer IC – CMOS Timer/Oscillator (CMOS) Data Sheet
mc14001 MC14001 – Quad 2-input NOR Data Sheet
mc14013b MC14013B – Dual Type D Flip-Flop Data Sheet
mc3456 MC3456/MC3556 Timer IC – CMOS Dual Timer/Oscillator Data Sheet
mc14069 MC14069UB – CMOS Hex Inverter Data Sheet
mc14093b MC14093B Schmitt Trigger – Quad 2-input NAND Schmitt Trigger Data Sheet
ne555 NE555 Timer IC – Timer/Oscillator Data Sheet
ne556 NE556 Timer IC – Dual Timer/Oscillator Data Sheet
pn100 PN100/200 – Data Sheets for the PN100 and PN200
lf13741 LF13741 JFet OpAmp – Monolitic JFET Input OpAmp Data Sheet
Thomas Thomas Scherrer’s (OZ2CPU) Website – Glowplug driver mod’s, UHF downlink, and more!
rce Brent’s R/C Electronic Page – Optoglow, Reverser, Go-slow, HotChek.
Daves Dave’s R/C Circuits – Couple very good circuits
Aichinger Johann Aichinger R/C Electronics Page – Excellent site, damn all those bloody pop-ups
Rutger Model Railroad Electronics from Rutger – Flasher, crossing, etc.
Stefan Stefan’s Electric R/C Website – Miniature Speed Controllers, and more!
Sirius Sirius Datasheets – for jumpering the charging diode in transmitters
Other Interesting Links – Links to other interesting and informative Electronics Websites

“Red” ball means LINK is off-line

DISCLAIMER: Tony’s Website, Michael van Roon & respected Hosts & partners,  take no responsibility whatsoever for the use and/or implementation thereof, or the misuse leading to damage to equipment, property, or life, caused by the above circuits. Check with local, provincial and federal laws before operating some of these devices. You may also check your life insurance policy and/or the fact if they cover death by electrocution if you intend to play with Micro-wave ovens and other possible lethal HV devices. Safety is a primary concern when working with high power circuits or con/inverters.

Play it safe!

Copyright © 1995, Tony van Roon (VA3AVR). ALL RIGHTS RESERVED.
Last Updated: January 13, 2011