history – Page 15 – Engineering Radio

The 100 amp fuse

I found this fuse in an old electrical panel that we were removing from the WICC generator shed. This was the original service entrance for the site as it was built in 1932 or so. The generator shed had a manual three pole two position transfer switch, which was fine back when a licensed transmitter engineer was on site whenever the station was on the air. The generator, according to the old records I could find, was an upright 2-cylinder slow-speed engine with a belt-driven generator. They were mounted on concrete pads about 5 feet apart. The motor had a big flywheel that was hand-cranked with the compression off. Once a good head of speed was built up with the hand crank, the compression lever was thrown and the engine would start. Alternatively, the procedure was tried again.

That was all replaced in 1971 when the transmitter site underwent a major upgrade. The old electrical service was bypassed and abandoned in place when a new meter and panel were installed in the transmitter building. The old service seems to have been frozen in time, untouched for forty years.

This fuse is a Kirkman Engineering Company and has a manufacture date stamp of January 1945. It is a replaceable link AKA “renewable” fuse. It has “peak lag” links, which I think would be called “slow blow” today. Peak lag may also indicate a large inductive load, which would lower the power factor. What I find interesting is that someone, once upon a time, placed two 100 amp links in parallel, then crossed the 100 AMP label out and wrote “200” on the fuse body.

The problem with this setup is that the panel and wiring were all rated for 100 amps. The wiring is #4 copper, and the transfer panel and switch are clearly labeled “100 amp, 3 pole.” It would appear that the finger stock holding the upper blade in place was loose, causing the fuse body to overheat. In fact, it became so heated that the case and the wood fiber holder were charred and missing.

Fortunately, there was never a fire.

The reason why we use properly sized fuses and breakers.

The 75th anniversary of FM broadcasting

On November 6th, 2010, WA2XMN will once again take to the airwaves from Alpine, NJ on 42.8 MHz. Beginning at 12 noon, EDT, the station will rebroadcast the 2005 commemorative broadcast. WA2XMN holds an experimental license which expires in 2015 for the purpose of recreating Armstrong’s original Yankee Network.

I am not sure if they will be using the GE Phasitron transmitter or not.

The Armstrong Tower is located just off of the Palisades Interstate Parkway, on a bluff west of the Hudson River. After the World Trade Center site was lost on 9/11, all of the NY City TV stations relocated there until permanent facilities could be build at the Empire State Building. Empire had always been the home to most of the NYC FM’s except public station WNYC, which was also on WTC #1.

Lots of interesting pictures and history on the Columbia University blog, here, here and here.

For those interested in the history of FM broadcasting, Empire of the Air by Tom Lewis is a great read.

On this, the 72 anniversary of War of the Worlds

It was early evening when most people were sitting down to enjoy the latest edition of Mercury Theater on the Air on CBS. After a brief narration by Orson Wells, which is set a year ahead of the actual date, there was a flash forward and brief weather forecast. It then seemed that the show was not going to be on as Ramon Raquello and is orchestra were performing dance music when the music faded down and the announcer came on the air slightly out of breath:

Ladies and Gentlemen, we interrupt our program of dance music to bring you this special bulletin from the intercontinental radio news…

It was a great piece of theater, too realistic for many, others tuned in late and panic ensued. People raced out of their houses, went to confession, and didn’t pay for gas. There were reports of long alien ships landing in New Jersey and incinerating crowds with heat rays. Then the black poison gas, oh, the black poison gas.

The day after, New York Times reported that up to 1.2 million people felt they were in grave danger and the world was ending. It is hard to imagine how they came to that number, especially overnight for printing the next day.

Naturally, those commie federal regulators were having none of it, and the FCC proclaimed that broadcast hoaxes would not be tolerated, even promulgating a rule, 73.1217, stating, in part:

No licensee or permittee of any broadcast station shall broadcast false information concerning a crime or a catastrophe if: (a) The licensee knows this information is false; (b) It is forseeable that broadcast of the information will cause substantial public harm, and (c) Broadcast of the information does in fact directly cause substantial public harm.

There are some radio stations that still broadcast this show every Halloween, with the appropriate disclaimers, of course. For those that want to hear the War of the Worlds, go to Radio Heard Here. It is really a great show.

Happy Halloween!

Update: Occasional reader Sandy sends along this link to the WKBW 1968 version, which was purported to be every bit as real as the 1938 version. The station was deluged with phone calls. In fact, legend has it that when the broadcast ended a little after midnight, show producer Jeff Kayne slipped his resignation letter under the General Manager’s door.

WOWO EBS activation

An oldie, but a goodie, February 20, 1971, WOWO gets an EAN via AP teletype and follows the procedure:

Back in the days of EBS, there were weekly closed-circuit tests via AP and UPI teletype. In the event of a real Emergency Action Notification (EAN) there was a red envelope that contained a set of code words for each month. The test code words were on the outside of the envelope. If an EAN was received, the envelope would be torn open and the actual code words would be matched against the code words in the message. If it were authenticated, then the station would do just what WOWO did right then, send the two-tone EBS alert for 25 seconds and break into programming.

It is amazing that this did not happen more often, especially on a Saturday morning with a sleepy Airman in Colorado pulling the wrong message tape off the rack at the message center responsible for the whole system.

It happened more recently when an EAS message was sent to evacuate the entire state of Connecticut. An EAN was sent in Chicago warning of a national attack when state officials were testing their new system. I am sure that others have been sent as well.

I suppose the emergency notification has always left something to be desired.