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It wasn't really just inertia. The generators also act as synchronous motors. Each ends up loaded more by the grid more when they're getting a bit ahead of the "consensus" frequency and less when they get behind. So once they get synchronized they stay that way. (Barring the occasional screw-up - which usually leads to a regional blackout.)

Also, it explains to people why it takes a while to get the grid back up after a large outage - not only do the generators (properly, "alternators") have to be operating at exactly the same speed to produce the same frequency of power, they also have to be in precise sync as to phase - or you turn hydroelectric dams into very large water pumps!

But if they're heavily loaded they slow down, and if lightly loaded they speed up. They have no inherent absolute speed referenc. So the power companies have to keep them "on time" by comparing them to a good time reference and giving a little extra push (with more steam or whatever) when they're getting behind, less when they're getting ahead - or by lowering the voltage (a brownout) or cutting off parts of the grid (rotating blackouts) when the load is getting too big for them to keep up to speed. If they don't, the generators get slowed down a tad and the clocks slow down. (That's what happened in Europe.)

When I worked for Litton, we worked a lot with generating plants on ships. I got to buy more than a few vibrating reed frequency meters.

The 50/60Hz mains timebase makes an amazing timebase for clocks of all sorts, not just those with synchronous AC motors. It's a dead simple case of taking a sniff of the incoming AC that powers the clock, rectifying it, and then counting the resulting pulse train to drive a display. Virtually everything with a clock and a power cord uses this system.

An hour is divided into 60 minutes (read that as minutes as in small), a minute is divided into minute minutes - second order minute portions of an hour, hence the term seconds. (Thanks to the great and very funny 1910 book Calculus Made Easy by Silvanus Thompson for that gem! See pages 3 and 4.).

Being a natural multiple, 60Hz is a better frequency as a timebase; gearing in mechanical clocks is easier. And our transformers are somewhat physically smaller for the same load than at 50Hz. The effect is peanuts in smaller devices, but in larger equipment it saves a lot of iron and copper.

This is discussed all over the web. Here's one cite that shows a Consumer's Union report of HV rectifier tubes in old TVs producing an objectionable level of X rays. http://www.antiqueradios.com/forums/viewtopic.php?p=1233533&highlight= There are lots of articles about a couple of early GE color sets with misaligned tube shields that produced even more.

My dad had (and still has) one of these cabinet stereos (except his has an 8-track player on top plugged into the "AUX" input):

http://www.antiqueradios.com/forums/viewtopic.php?t=122551

My TV speakers sound better than this stereo.

For every dad that had a true Hifi system 30 years ago, there were a dozen dads that had a crap stereo. It's the same today, the dads that care about audio will go into their audio retailer and listen to various systems to find the one that sounds the best.The rest of us that don't need the ultimate in sound reproduction will just buy whatever is on sale at Best Buy and has the right inputs for our other A/V equipment.

There are still companies that focus on sound (NAD comes to mind), but you have to pay a premium and to be honest, most people with a stereo in their livingroom aren't going to notice a difference between a $200 Sony and a $2000 NAD receiver with $2000 speakers.

I used to buy parts 'at the last minute' at the rat shack. now, I don't even bother looking anymore and instead just hit up the only valid mailorder places left: digikey, mouser, newark are the big 3.

their parts are cheap enough, they work, they web ordering works and the selection is world class (literally, many people across the world order parts FROM the US distributors and even pay VAT/customs to receive the pkg).

I go into a rat shack and I see candy, cellphones and an ever dwindling parts selection.

they don't even carry x10 powerline remote stuff anymore (that used to be a stable at the shack).

I might as well turn in my radio shack battery club card:

http://www.antiqueradios.com/gallery/v/temp/battofmonth2.jpg.html

This asswipe needs a vacation from lawyer-land back in the real world. Since he wants to compare DRM to computer hardware, let's take a real-life example: my Compaq LTE/386:

Let's take an even better example: These perfectly functional Rogers-Majestic Radios.

"Rogers", as in "Ed Rogers, Sr.", the guy who figured out that if you could build a radio out of vacuum tubes, and had a really big radio to broadcast with, you could sell ads on the radio broadcasts to people who wanted to listen to the music... and lots of vacuum tubes to people who wanted to build radios for listeners. Anyone in Canada who curses the name "Rogers Communications"... well, yeah, the industry sucks and the company deserves your vitriol. But the Ted Rogers' dad was a hell of an engineer.

Long story short - even without any maintenance whatsoever, a radio that's more than twice as old as I am... still receives radio broadcasts from the station he founded.

That's what I call hardware in perpetuity.

In March of 1939 The St. Louis Post Dispatch began experimental public broadcasts of a nine page facsimile newspaper to the home using technology developed by RCA.

"So far as the transmitting equipment is concerned, it is the standard scanner manufactured by RCA, the output of which is fed into a 100-watt transmitter operating on 31,600 kc. We selected the ultra-high frequency band because it offered the opportunity of broadcasting facsimile during the day time--in fact any time we desire.

We have not experienced nearly as much trouble with interference on the ultra-high frequency band as was expected. The characteristics of the recorders are such that far more interference can be tolerated than is the case in the reception of sound broadcasting an these frequencies."

Within the next month RCA expects to be able to supply receivers at a cost of about $260. Several will be placed in public places for demonstration. The range of Station W9XZY is from 20 to 30 miles.

"On the first page of this "radio newspaper," now being received in every home in the St. Louis service area of W9XZY equipped with a facsimile receiver, are the leading news articles of the day. Then following sports news, several pages of pictures, Fitzpatrick's editorial cartoon, a summary of radio programs and radio gossip, and a page of financial news and stock market quotations."

The antenna of the receiver set in the home picks up these waves. The receiver, a closed cabinet with no dials to be operated or adjustments to be made by the owner, contains continuously-feeding rolls of paper and carbon paper which pass over a revolving metal cylinder from which a small stylus projects.

Pressure, varying with the intensity of the radio waves, is exerted on a metal bar, parallel to the axis of the cylinder, beneath which the paper and carbon is fed. Thus the black and white of the original copy scanned by the "electric eye" is duplicated on the paper passing over the cylinder of the receiving set which is synchronized with that of the sending mechanism.

It is unnecessary for the reader to be on hand when a broadcast begin since a clock, set for the scheduled time, will automatically start the receiving set and stop it at conclusion of broadcasting. It requires 15 minutes to transmit one page.

First Daily Newspaper by RADIO FACSIMILE
[as published in Radio-Craft, March 1939]

I was wondering this the other day when I read some random posting on the internet about a guy who cleaned out a 1930's era RCA radio and crammed a miniITX board inside. What happened to the radio? He threw it in the trash.

This worries me because that radio was created during a time when Analog sets were state-of-the-art and cost upwards of hundreds of dollars. The PC components he placed inside that wooden case probably cost the same, but will be obsolete in a few years due to the speed at which we are updating technology these days. The radio however, was probably in use for well over 20+ years until a tube burned out and the previous owner could no longer get a replacement.

20+ years Vs. 2-3 years. I prefer keeping vintage electronics whole and in one piece. There are tons of resources out there for people who would love to get their hands on old sets and get them working again. The PC in an RCA case will probably be forgotten and discarded not soon after it's internals are considered yesterdays news. Much like it was decades ago, only that much sooner.