Not-So-Great Moments in Ham Radio History: The Repeater

Welcome to the first in a series of articles that take a cursory, historical look of different facets of amateur radio. Rather than focusing on the people who made things happen, these articles will be more subject-oriented.



In a recent article thread here on eHam, it was lamented that cell (or mobile) phones and the Internet have pretty much supplanted the need for amateur radio repeaters, that their utility has come and gone with advances in technology. It's a lonely job for them to be sure: sitting on top of a hill, tower, or building; subject to the heat, cold, and inclement weather. They're the ham radio equivalent of the Maytag repairman. Their importance can't be overstated, though: they're an important link in delivering a message from its source to its destination.

Some of us can remember--or were there--when the first repeater came on-line in 1954 in San Jose, California...or was it really the first repeater? Some may argue that the first true repeaters were Morse code operators in the mid-19th century who would relay messages across the country--they were vital links in the chain who transmitted messages from one place to another. (We still carry on their heritage today with such organizations as the ARRL and the former CRRL--the second "R" is for Relay.) If you want to use "relayer of a message" as the definition for a repeater, then you'll have to go back a few more years than 1954; say around 2,000 of them!

The first repeaters were arguably bonfires: they were built on coasts, hillsides and towers and were frequently used by ancient Romans, Chinese and Egyptians. The advantage of using these kinds of beacons were that they were easy to set up: gather wood or other combustible material, light it on fire, and "whoooooof!" Instant attention-getter. The problem with it was three-fold: 1) you needed something that burned, so if you were surrounded by sand or water you were out of luck; 2) you needed people posted at dedicated sites for beacon watching, and 3) it didn't transmit any information other than "Hey, over here!" or "Uh-oh" the latter one being of real importance in the year, 1588, when a series of bonfires placed between Cornwall and London were lit to let the British Navy higher-ups know that the Spanish Armada was on its way. It worked: the message got through faster than any horseman could've delivered it, and seeing that they speak English, instead of Spanish, in the U.K., you can pretty much guess who won the battle.

But I'm jumping ahead of myself by a few thousand years. Sorry.

The next recorded repeaters (dated 400 B.C.E.) were heliographs: polished brass mirrors--or soldiers' shields--that reflected sunlight. (Alas, the problem with that was that heliographs only worked half the time.) It was a no-brainer: twist the mirror or shield in the Sun to either send coded signals to a friend, blind your enemy as he approached, or use _en masse_ to light ships on fire in the harbor. As a signaling device the Roman emperor, Tiberius, used a heliograph to exchange messages with the mainland from his pleasure palace on the island of Capri, eight miles away.

Early in the 19th century--1810, to be precise--a guy who was playing around with magnetism perfected a mechanical heliograph. He was Professor Carl Friedrich Gauss. (Hmmm, where have we heard that name before?) Originally, it was used for surveying the German countryside but you know the military: they can't leave promising technology alone. So, within a few decades the British and American armies began using the heliograph as a wireless Morse code signaling device; electric lights later replaced the Sun as a light source. (Remember all those WWII movies with the ships at sea sending messages to each other [while under radio silence] using a shuttered light? Technically, that was a heliograph.)

Oops. Once again I'm getting ahead of myself.

From the "where there's smoke there's fire" department, consider smoke signals. Yeah, yeah, we've seen countless Western movies where the Five Nations native Indians used smoke signals as a repeater, but they didn't invent that trick: go back a few thousand years where the first record of using smoke signals goes to the Picts, the warring folk who fought the Romans stationed along Hadrian's Wall in England.

While we're on that side of the world let's jump to the year, 1794. Claude Chappe, a Frenchman, and his brothers created a string of semaphore repeating stations for the French military along France's coastline. These stations had pivoting arms that, when turned to specific positions, sent coded text. (See the attached pic and view this link: http://www.archives.lib.soton.ac.uk/wellington/peninsularwar/transcripts/semaphore_trans.htm ) It was very effective; so effective, the British had to have a version of = their own. With it, they were able to send a message from London to = Portsmouth--a distance of 60 miles--in 30 seconds. (For you proud French = folk, Chappe's system worked better and faster.)

Fast forward to the year, 1872. Morse code has been around for awhile, but the problem of repeating messages automatically was up 'til then a problem: you needed a competent telegrapher around to retransmit messages. (For grins, read the following "Instructions for Telegraph Operators" written in 1837: http://labit501.upct.es/ips/libros/TEHODN/ch-2-9.4.html ) A notoriously famous cheapskate and "robber baron", Jay Gould, commission ed a then up-and-coming telegrapher, Thomas Edison, to build an automatic repeating telegraph so he wouldn't have to pay telegrapher's wages, which he did. (Sorry, but I haven't been able to find a link with a good picture of one. Here's one of his repeating telegraph discs, though: http://www.p4a.com/itemsummary/156584.htm ) It worked as follows: the receiving telegraph would use a stylus to punch holes in a rotating paper disk in time with the code. After the message was recorded, the operator would place the stylus of the sending Morse code key on the paper and through gearing, it would track the holes: the stylus would dip in the hole and thus send a dit or a dah. (Precursor for the phonograph record, the CD, and the DVD.)

There was a quantum leap in amateur radio in the 20th century with the creation of the first, true repeater in 1954 by a talented group of ham ops in San Jose, California; which interestingly was on 2-meters _AM_. ( I can't do justice to this part of the story any better than Bill Pasternak, WA6ITF, did; he wrote about repeater pioneer, Art Gentry (W6MEP, SK). Check out: http://www2.arrl.org/qst/2004/03/pasterna.pdf .) When FM came into its own, repeaters went FM because, among its many benefits, it was relatively free from QRN.

Then another big leap came with solid state repeaters coming into their own in the 1960s and 1970s; and they didn't stay on the ground, either: beginning in March, 1965, the Oscar series of amateur radio satellites opened the door to provide worldwide, repeater-type coverage that our radio forefathers could only dream about.

Finally, there's the largest and oldest, albeit passive, repeater of them all: the Earth's moon. It's a treasured QSL card that confirms a QSO by way of the Moon! (Note to self: using the Moon as a repeater works much better when it's above the horizon.)

I hope you enjoyed this brief history of repeaters. My thanks go to Zak Lau, W1VT, at the ARRL for his help in filling in a few holes. Feel free to use this article any way you want. Just remember, though, to give credit where it's due, as if that bears repeating. *groan*

Ciao!
Rich, WF7A

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