Introduction - (About me page)   AWA company collapse 1987
The Shipping News 1984-95      Seagoing Radio Officer: Exam Syllabus
Economical Valve Audio Power Amplifier
Economical Valve Audio Power Amplifier
"Eu version" 25E5/PL36
Telephone Ring Generator Mk I Telephone Ring Generator Mk II
DTMF decode store and display Mk I DTMF decode store and display Mk II
The Siemens Neophone Linesman's Buttinski circuit
X-Y CRT Indicator
Digi-display for CRO
CRO trace doubler Millersweep sawtooth oscillator
The Lambda (λ) Diode The Schottky Diode (& transistor)
100/200/400 Hertz - Frequency Reference Kalitron oscillators
Pocket sized Metal Detector Metal Detector with only 4 components
Transformer Design Simple high curent DC voltage-regulator
Battery Charger Voltage regulator for Car Alternator
13.8 Volt 20Amp DC Supply (SMPS) Radio 'B' battery circuit (DC/DC converter)
Voltage Multiplier circuits Volt, Amp, Ohm Meter (Analogue)
Joule-Thief (voltage boost) circuit
Theory & Application
Ferrites - the 2 types
In-circuit Transistor Tester Transistor curve tracer for CRO
FET (Power Mosfet) tutorial CMOS buffered/unbuffered 'The TRUTH'
FET Dip Meter (HF) FET Dip Meter & Impedance Bridge
FET connections Single Mosfet FM wireless-mic
LC Meter    (PIC16F84A based) Frequency Counters - 3 designs
Frequency Meter (PIC16F628A based)   DDS Frequency Generator ~55MHz  
Coaxial cable:
Impedance & Standing Waves
p - Couplers
Magnetic Loop Antenna (MF & HF) Remote Tuned Magnetic Loop Aerial
HF Antenna Tuner (manual) SGC Antenna Tuner (Auto)
Log-Periodic Antennae 50 MHz 4 element Yagi Aerial
RF conductivity SKIN EFFECT & Litz wire RF conductivity SILVER PLATING
Magic Eye Demonstration EPROM burner/programmer
Restoration of "old" Radio Transmitter Pre-emphasis & De-emphasis - FM broadcast
FREMODYNE - VHF receiver "Pulse-counting" type VHF FM radio tuner
HF valve receiver - regenerative 1 Valve Regen' receiver 12 DC Volt powered
A "CIGAR BOX" RADIO (B'cst Band) MK484 based radio designs
H.F. SUPERHET receiver Mk I H.F. SUPERHET receiver Mk II
H.F. SUPERHET/HOMODYNE rcvr Mk III AM VHF Air-band Receiver (passive)
Icom R8500 DBM I.F. mixer mk1 Icom R8500 MOSFET I.F. mixer mk2{WIP}
RF Mixer (diode ring) RF Mixer (cmos & mosfet)
SDR - Software defined Radio (Q.S.D. ) SDR uses USB dvb-t TV tuner 'dongle'
"Lidia" 7MHz Direct Conversion Receiver    
SSTV - the Analogue Chronicles (c 1970's) SSTV Digital modes
Radio-teletype RTTY decode & display Encryption - An Ancient Art    
Electret microphone - Compressor Electret mic' needs no DC supply ?
Ultra Linear Audio Amplifiers - observations Audio Output Stage
WW 2 Radar letter band designations ITU RF emissions designator: look-up table
Fractal Type Antennae VHF Propagation
Could East-West Ch 2 TV-DX propagation be possible during 2013 ? some ideas. Yagi-type antenna for "Digital" TV reception
162MHz for PROPAGATIONIST's Yagi antenna for 162MHz AIS data reception
10 Metre/28MHz band radio beacons   Line Section Impedance Diagram
SWR meter (Reflectometer) Design #1    Design #2 Handbuilt Rcvr uses EDDYSTONE 898 dial
Complimentary AWV QSL card 1960's Amateur Station - G5BD 1930's
Australian MW Broadcast stations - history
c 1923 - 1990 (Excel spreadsheet)
US ham call zones
The "S" meter
Potentiometers explained
Accu-Keyer IAMBIC morse keyer Roger bleep circuit
From the Serviceman Who Tells - (Nr1)
AM Car Radio for XY Ford Falcon
From the Serviceman Who Tells - (Nr2)
Valve(Tube) based Audio Amplifier rebuild
Soviet Valve Manufacturer's STC & Stromberg Carlson headphones   
RC (radio-control) Servo Test Jig INTERCOM circuit design: uses obsolete electro-mechanical telephones
Amateur Radio - MENTORING {VK3BB} Working esteemed persons on the ham bands ! (73 magazine)
RF Mixer - What is a DIPLEXER ? Class D and E amplifiers
Wireless World Technical Articles
by M G Scroggie AKA "Cathoderay"
  Triode 25 watt Audio Amplifier
▄▀▄▀▄▀   Frank's "FIXIE" 2011   ▄▀▄▀▄▀ ▄▀▄▀▄▀   Frank's "FIXIE" 2012   ▄▀▄▀▄▀
Fixed-gear bike : chain tensioning Wheel-building (Bicycle)
Car Alarm Alarm Siren circuits
2 Terminal Flasher for Automobile My Car
U.S. military 'Command' Receiver Command Receiver - Frequency Convertor & Power Supply
Electronic modules (ex China) 7 MHz SSB transceiver "Knobless Wonder Design"
MAR6 RF amp (VHF satellite S S T V rcvr') MMIC SGA-3486 International Space Station ISS
Radiodata & Video monitoring
Masthead Amp with discrete components Satellite tracking goes WIRELESS
LM386 IC Audio Amp - Improving Performance ISS live-data decodes on an Iphone
Using the NE602 balanced mixer/oscillator Australian MW/Broadcast Radio 'off-air' recordings from 1960/70's
CRT Greenscreen A-V monitor       (W.I.P.)   Neon Novelties
Lissajous pattern generator   913 1" CRT test jig  
(Sinclair) Thandar SC110 CRO   (Sinclair) IC-10 Audio Amp'
(Sinclair) Transistor pulse-count VHF-FM receiver (1966-2016) American Mosaic        
Radio Mi AMiGO (offshore-radio themed) broadcaster in Eu        H.F. Digital Broadcast
7 MHz band CW Transmitter 1948 QRP transmitter (low parts count)
Dimitri Mendeléeff and his periodic table 1960's H. B. SELBY Catalogue
2 Chip Frequency Counter Low Freq Xtal Oscillator 2/4/8 ....32,768Hz
Tuning Capacitors - some theory JFET Regen' Receiver with Digital readout
Hi-Z Bootstrapping - an explanation, Delta Modulation
Single-Transistor Radio Beacon LIPD Radio Beacon (36.625MHz)
Tone-Modulated Radio Beacon Radio Beacon Receiver's
(2 designs)
455 KHz B.F.O. (JFET) LEADER Signal Generator
Basic Laws of Trigonometry Basic Laws of Electricity
Power & Voltage ratio in Decibels E explained (2.71828 naperian logs)
When is a not a triumph ? twin 270°/450° or 360°/360° firing interval which is best?
Desmodromic Valve Gear - explained     Flywheel Sludge Trap - clean   
The Earles Fork (Motorcycle)     FORD V8 Engines - firing order
Camshaft theory Pt 1 Camshaft theory Pt 2
Chevrolet (1955-57 'shoebox' types) Spotters guide Chevrolet Corvette 1953-1990 Spotters guide