[AMRadio] AM Radio

[Eddy Swynar]

Hi Guys,

While I certainly don't claim, or even pretend to be, any sort of an "expert" on AM fone, it has become rather  obvious to me from a few of the comments made herein of late that there are many of us out there in "radio land" who would benefit tremendously from a read of the modulating specifics outlined in the first edition of the ARRL's classic book, "UNDERSTANDING AMATEUR RADIO"...

There are even some easy to follow guidelines to the construction of your own HB AM rig, and all kinds of neat little tidbits that some of us may be unaware of.

For instance: did you know that any commercial AM modulation transformer may be safely operated at TWICE its advertised power rating...? Wattage for mod iron is quoted using sine wave audio: the human voice is hardly that, and so a modulation transformer rated at, say, 30-watts, may be safely used in a 60-watt application---as long as all you'll ever do is talk into it.

This was made perfectly clear to me several years ago when the modulation transformer in my Johnson Ranger-1 transmitter expired. I happened to have a 15-watt Stancor universal mod transformer in my junque box, and I was surprised to see that it was practically the exact same size, physically, as the original "30-watt" transformer that came with the rig! Anyway, based upon what I learned in the ARRL book, I subbed the Stancor into the spot previously occupied by the defunct iron, & the thing worked superlatively for years afterward, right up to the time that I sold the transmitter...

It pays to have an expansive "hard copy" library...I heartily recommend anyone interested in the AM mode---or homebrewing, in general---to acquire a copy of this wonderful little book.

~73~ de Eddy VE3CUI - VE3XZ