From vintage tube-based gear, to military surplus, to modern, ultra-efficient FET-based Class E transmitters, Amplitude Modulation (AM) offers the experimenter, homebrewer, and radio restoration buff great opportunities to learn, build, and enjoy radio. AM was once the main voice mode in amateur radio. Now it is a well regarded specialty within the hobby. AM offers a warm, rich audio quality that provides for more personal interaction. The simplicity of AM circuit design encourages hands-on restoration, modification and homebrew construction to an extent no longer found among contemporary radios.
This web page was created and is maintained by Steve Ickes, WB3HUZ. Stephen Ickes, WB3HUZ, was introduced to amateur radio as a shortwave listener tuning into 75-meter AM activity in 1976. He obtained his license through a middle school ham club in 1976. Since then he has been involved in AM and related activities both on and off the air. He is a charter member of Amplitude Modulation International (AMI), an organization of AMers dedicated to the enjoyment, promotion, and preservation of the mode. He has served as the Northeast Regional Director since AMI's inception in 1993. In 1997 he started The AM Window Web Site that has grown to over 50 Megabytes in size and continues to serve amateur radio operators world wide.You may contact the author directly at email@example.com about the page or its contents. ARRL extends its thanks to the volunteers that help make ARRL's web pages a useful resource for all.
·Classic Rigs and Amplitude Modulation: Friendly, Nostalgic Ham Radio Partners
QST February 1993, pp. 43
An introduction to current day AM activities within Amateur Radio.
Some Principles of Radiotelephony.
The basics of AM in four easy parts.
·A Course in Radio Fundamentals, Part 6 -- Modulation
QST November, 1942, p. 53
Another good AM primer.
Introducing: The AM Radio Network
QST December 1995, pp. 46
More on current day AM operation.
Hams Redeem Old Transmitter at Fountain of Youth
QST November 2003, pp. 56
The story of a rescue and Restoration of a Collins 300G Broadcast Transmitter
·Audio Preamp with AGC and Feedback to Improve AM Fidelity
QST November 1997, pp. 36
A sweet little mic preamp that also helps control modulation levels.
·Constant-Carrier AM for the Drake Twins (Hints and Kinks)
QST November 1994, pp. 85
Make these venerable radios sound much better.
·Technical Topics - Some Facts on Modulation
QST March 1951, pp. 49-51, 116.
An excellent explanation of how AM works. A good read for beginners and old-timers alike.
·Technical Topics - Linear Amplifiers for AM
QST Feb 1956, pp. 39-41
There's more than one way to generate AM. Get the scoop on using a linear.
ARRL Handbook, 1929, pp. 98-107
See how AM was done in the early days.
·Lop Sided Speech and Modulation
QST February, 1940, p.14
Get the straight dope on speech asymmetry and its application to AM.
Three Control Six-Band 813 Transmitter
This transmitter was all the rage in its day and would be the envy of many AMers today.
·The Ultra Modulation System Using Higher Audio Power Without Splatter
QST, October 1956, pp. 27-29
Shows how to increase modulation peaks for more effectiveness.
An AM/CW Exciter for 144 Mc.
QST September 1965, pp. 39
Try some local contacts without the repeater.
·Synchronous Detection of AM Signals
QEX September 1992, pp. 9
A great primer on sync detection and the advantages of using it for AM signals.
·A Simple Synchronous-AM Demodulator and Complete Schematics for the DDC-Based Receiver
QEX September 1997, pp. 3
·A Synchronous Detector for AM Transmissions
QST July 1993, pp. 28
Build a sync detector for yourself.
·Synchronous AM Detectors
QST September 1992, pp. 65
· The AM Window
This web site, previously featured in the Surfing' column, contains extensive coverage of AM topics, including information on construction and modifications, AM operating events and social gatherings, AM Nets worldwide, audio and visual coverage of AM stations and operators, and much more.
· AM Fone.net
A vast storehouse of AM information and regional coverage of AM operators and activity. This site also feature a bulletin board for quick and easy access to AMers around the globe and their radio knowledge.
· The Official Class E Transmitter Web Site
The goal of this site is to present a working, practical tutorial on class E transmitters (a complete explanation of class E is included), and to provide sufficient information to allow someone with reasonable radio experience, technical skills and knowledge to construct a working class E transmitter or design a transmitter using similar RF and modulation methods.
· Class E Forum
This forum is for technical support and general questions about building and operating Class E-AM transmitters. Tap into the experts' knowledge!
· Electric Radio
A monthly publication covering the vintage and AM aspects of Amateur Radio.
· Synchronous Detection of DSB and ISB Signals
A Synchronous Detector designed with the use of an LM311 and an Analog Devices AD607 by Pete McNulty, WA1SOV
· Broadcast Transmitters on the Ham Bands
Hams Give Second Life to Legendary Transmitters With Names Like RCA, Collins, Gates and Raytheon.
· AM Forever
For ham radio operators and shortwave listeners interested in learning and preserving the practice of receiving and transmitting amplitude modulation.
· Boat Anchor Manuals Archive - BAMA
This archive has manuals for every major radio manufacturer and quite a few minor ones.
· Searchable Tube Database
Enter a tube type and get pinout, characteristic and sub data. Close to 3000 types including transmitting and receiving.
· Tube Data Sheet Locator
A database search engine which contains links to valve/tube data on the web.It also contains short form data and pinout information on many valves, and a list of substitutes.
· Live Audio Stream of 3885 kHz AM
Listen to the AM action while you surf the Web.
· The Southeastern AM Radio Club
AM Radio in the Heart of Dixie.
· AF4K / G3XLQ's Ham Radio Files
Hundreds of links to tube and vintage radio info, parts and projects by Brian Carling, AF4K, aka G3XLQ
· Frank's Electron tube Pages
Tube data sheets for almost 10,000 different types, including European and Russian types.
GE Ham News—the complete set from 1946 to 1963.
Send us Your Photos!
Would you like to see your AM station on our web site? Send your photo as a JPEG file to me and if it's of good quality, I'll post it!
Send to Bob Allison, WB1GCM ARRL Test Engineer at: