It's a fascinating time and a critical point in the development of western culture. When Eric contacted me and asked that I help brief him on the possibilities for radio in 1632, it became quickly clear that from a radio specialist's perspective, Eric could not have chosen a worse time to drop a town into than 1632.

Just at the beginning of the period where there are telescopic observations of the heavens, approximately simultaneous with the trial of Galileo, 1632 drops Grantville into the beginning of a time best known to science as the "Maunder Minimum."

]At about the same time as Galileo published his description of his construction of the Dutch invention of the telescope, natural philosophers throughout Europe began noting that the sun had imperfections, "spots" on it. This was far easier to watch with a lens, since you could project an image of the sun onto a white sheet, and observe it without destroying your eyes. The novelty led several natural philosophers to begin a program of noting the sunspots on a regular basis. Therefore, we have an excellent European record of the number of sunspots starting with Galileo's first such observation in 1610.This notion of the imperfection of the sun would have come as no great surprise to the court astronomers of China and Korea. In the court logs of the observations of those staff astronomers, there are sunspot records made with the naked eye going back another millennium and a half. Using those records, we can trace the sunspot number from about 28 BCE, using a reasonable relationship between the capabilities of naked-eye astronomers and those using projections and lenses.

For all of this two thousand year period of recorded observations, the number of sunspots on the surface of the sun has varied in an eleven-year cycle. As of this writing, in 2003, we are near the falling side of the peak of the current cycle with sunspots near the historic high of over 200. This extreme activity has resulted in spectacular auroras being seen as far south as 30 degrees north (Oklahoma City). At the other end of the measure, the lows have had sunspot numbers in the low teens to the mid-20s. The "average"low is between 20 and 30.For reasons that no one understands, starting in about 1610, the number of sunspots plummeted. By 1632, which should have been a peak year, the sunspots were down to the mid-teens, and by 1640, had dropped to zero. (There is an anomalous high data point in 1639.) The 11-year cycle did continue, with peaks as high as 8 or 9 between 1645 and 1700. Then, again for reasons that no one understands, starting in 1710, the numbers went back up, and have continued quite regularly for the last three hundred years. This isnot a "lack of observations" artifact, since the court observations in China and Korea correlate quite well with the western records. This is real.Recent work by observational astronomers using a combination of new techniques by really really smart people on type G2V stars like our sun have figured out a way to measure the sunspot number of a star even though we cannot "image" the star. This work indicates that G2 stars may typically spend as much as 20% of their time in this "quiescent" mode. It could start again tomorrow. No one has any models for why it happens, or what causes it, or why it stopped. It's all quite confusing. So what, you say? Well, it turns out that the number of sunspots is very highly correlated with the thickness of the upper layers of the ionosphere. There are several "layers" in the upper atmosphere, which get ionized for different reasons. These are labeled, from the outside in, A through F.The innermost F, E, and D layers are caused each day by the action of ultraviolet light on the earth's upper atmosphere. This is the same action that splits O2 apart and gets the free oxygen that can combine into O3, to form the "ozone" layer. These ionization layers form every morning at sunrise, and thicken throughout the day, and then begin to fade at sunset. The combination of their chemistry and their electrical properties causes them to absorb radio waves longer than about 4 MHz. That's why, during the day, you can only hear your local AM radio station; but at night, you can pick up the one from the other side of the country.Shorter wavelengths pa.s.s right through the DEF layers.Further out, the ABC layers are ionized not by UV light, but by the action of the solar wind on the outer layers of the earth's atmosphere and its interaction with the earth's magnetic fields. During periods when there are lots of sunspots, the sun puts out a lot of particles, and these ionization layers are quite thick and robust. Without the solar action, during sunspot minima, the ABC layers are thinner and weaker.The thicker and more robust the outer layers are, the shorter the wavelength they can refract or reflect.During sunspot maxima, the maximum usable frequency (MUF) can get as high as 30 or even 50 MHz (six meters). That is, 30 MHz signals can bounce right off the ionosphere, or be trapped between two upper layers and ducted around the world before breaking out and coming down most anywhere. That's how CB radio "skip" works, when folks listening to the radio in their cars on the highway in Kansas hear the chat between boats working the shrimps in the gulf of Mexico. Normally a CB radio is good for 5 miles, but when the sunspots are high, all bets are off.During a normal sunspot minimum, when the sunspot count is down around 20 or 30, the MUF stays up around 14 MHz for at least part of the day, and seldom goes below 7 Mhz.Frequency and wavelength are related. The higher the MUF, the shorter the wavelength and the smaller the antenna that is needed to send and receive radio signals. In general, one wants to use as short a wavelength as possible, because the higher the frequency, the smaller the antenna needed. A 30 MHz transmitter uses a "natural" antenna that is only three meters long. But a 7 MHz transmitter uses a natural antenna that is about twenty meters long. [NOTE: Wavelength in meters = 300 / Frequency in MHz. A "natural" vertical antenna is one quarter wavelength long. A "natura" horizontal antenna is a half-wavelength long.] Thus, the higher the MUF, the more convenient it is to build radio installations.Most Hams therefore work the 20-meter bands, and the 40-meter bands are not uncommon. But it's the rare Ham who works 80 or 160 meters, since the natural antenna for 80 meters is 40 meters long, and 80 meters long for the lowest common Ham band of 160 meters.However, remember the missing sunspots? During the Maunder Minimum, during the period that Eric has set the 1632 series in the middle of, the ABC layers of the ionosphere go away to a great extent. Of course, there is alwayssome solar wind, and there will be some ionization and some reflection. But the MUF keeps dropping and dropping until, by the year 1640, to do long-distance communications without relays you would need to be using 2 MHz for much of the day, and can get up to 4 MHz only late at night.And remember that the DEF layersabsorb the long waves, so the low MUF means that you have little if any ability to do long distance communication during the day at all.So, the radio installations in 1632 universe end up usingvery large antennas. The most common antenna for a diplomatic mission will be installed this way: Take a piece of wire, forty meters long, and cut it in the middle. Put a gla.s.s insulator in the center of it, and hook another piece of wire to each of those twenty-meter-long pieces. The "hookup" wires are held apart every few inches by a hunk of gla.s.s or plastic or wood, like a little ladder two inches wide. This ladder leads back to the transmitter. Meanwhile, take your center insulator and haul it up to the top of a tower as high as you can get. One hundred and fifty feet is really a good height. Attach the gla.s.s insulator to the tower, and then, draw a line on the ground, in the direction of the city you want to talk to the most.Stretch each of the twenty-meter-long legs away from the tower at 60 degrees up from vertical, 30 degrees down from horizontal, and perpendicular to the line you drew (crossing it). Then hook the end of each wire to a rope with another gla.s.s insulator, and pull the ropes taut so that the wire is as straight as you can get it.Now, remember how you drew a line towards the radio you want to reach, that you want to "beam" at?Build another tower, 20 feet back away from your destination, on that line. Now, do the exact same thing with another piece of wire on that tower. (You do not need hookup wires on this one.) So, two 150-foot towers, two 40-meter long hunks of wire, suspended in the air, and lots of rope. If you want to use 1.7 MHz (160 meters) instead of the 3.5 MHz we designed this for, double all the numbers above. (Well, you can keep the tower height the same, but taller is better.) Repeat this, as often as necessary to build a beam pointing at each city you want to talk to. A big central diplomatic radio installation will have a cl.u.s.ter of these beams pointing in a variety of directions and will require a clear level s.p.a.ce a quarter of a mile on a side.You begin the see the problem...As the characters in the series approach 1640, the electronic situation in the atmosphere worsens. The MUF drops towards 1.7 MHz, and the antennas and such get bigger as above, and harder to build. It's not fun. That's why Gayle and Jeff kept muttering about the bad timing of the radio situation in1633 .From the perspective of a Ham, they were dropped straight into h.e.l.l.What can be done about it? Several things: 1) You use a lot of power to overcome the fact that not much bounces.2) You experiment to find the best frequencies available and use them.3) You build good antennas.4) You send your messages at the right time of day (generally a window about four hours long starting at sunset called the "gray line").5) You set up relays, i.e., you send the message as far as you can, and then relay it. Thus, in1633 the mission in Amsterdam relays to London and to Scotland.6) You maximize the use of the power you have, by using CW (Morse code) instead of voice. Voice requiresfar better signals than CW does.Very awkward, yes. But that's the situation until the newly emerging society can get satellites back up, which will be a long time yet-in fact, at least as long as the year 1700, which is about the same time that the short-wave bands will reopen.In short, no matter how you slice it, long-distance radio communications will be a very different thing in the 1632 universe than what we've experienced in our own timeline. And as tube production comes on line, and high power radios go into production around the world, bandwidth for long distance communications will be a precious and rare resource. The pressure to build cables across the ocean will be even higher in the 1632 universe than it is in ours.The Physical Resources In addition to the physical world around them, the radio situation in Grantville is shaped by the technological world they brought with them. What radio technology does Grantville posses? What just won't work? Let's examine each of the common up-time radio technologies and consider its place in Grantville after the Ring of Fire. When Eric began writing1632 he did a very clever thing. He decided that with a few exceptions which he has carefully limited, Grantville is based on the real-world town of Mannington, West Virginia. In general, and with a few specific exceptions (the main one being the power plant), it's safe to a.s.sume that if something was in Mannington in late 1999 or early 2000, it's in Grantville; and if something was not in Mannington then, it is not in Grantville. That presumption drives the following discussion.Stores There is not a Radio Shack store in town, there is no electronics store, there is no radio dealer of any kind. Some CB radios will be available at a few stores. There is one TV repair shop.Cell Phones Sadly, while there was a cell phone antenna and cell in both Mannington and thus, in Grantville (an a.n.a.logue one-no CDMA or TDMA digital cells were operating in Mannington in late '99 or early '00), the cell was not linked to the local phone switch. It was operated by a different company. And while one of the short stories from theRing of Fire anthology (coming out in January, 2004) explains that there is an excellent phone tech in town, he's not a cell phone guy. It may be possible eventually to cross connect that cell to the phone system, but in the first two years, no one has had any success at it. The manuals for the cell weren't in town, no one knows the computer pa.s.swords, and the cell was not set up for autonomous operation. The cell phones themselves are useless without the cell being attached to a billing and authorization computer system and to a phone switch. For all practical purposes, you may regard cell phones as a source for small high energy density rechargeable batteries and other electronics parts, but not as radios.Commercial Radios Pre-Ring of Fire handheld and base station commercial FM radios were used by the coal mine, by the electric company, the police, the school district, the city water department, etc., etc. The presumption of the 1632 authors is that these radios remain dedicated to their pre-RoF use. One radio from each incompatible frequency set was placed in the Grantville emergency Operations Center to provide crossnetwork links.CB Radios CB radios are featured in1632 because they were owned by Mike Sterns and his friends, as well as many other residents of Grantville. CB radios are common in the U.S., particularly among rural populations prior to the wide spread of cell towers. They provided unlicensed, free, simple radio communications for a variety of purposes. It was automatic that the Stearns administration began to use the CBs to coordinate the new military actions that Grantville found itself engaged in. By the end of1632 , CB radios are primarily used by the military for tactical coordination.CB radios operate at 21 MHz (11 meters) and are well above the MUF described above. Without relays, they are good for one to five miles on level open ground. The signals are blocked by hills or mountains. CB radios in airplanes, or situated on mountain tops can generally talk about 20 miles line of sight. Of course, we can relay over-and-over and go any distance.Four types of Pre-RoF CB radios exist: 1) Children's toy walkie talkies. These are useful for small-area crowd control type operations. They would have been gathered up where possible and pa.r.s.ed out as needed-except some kids refused to give them over and... it's a free countrylet. There are probably twenty to a hundred total in the town.2) "Base" stations designed to operate off the 110V mains. There are probably between twenty and forty in the Ring of Fire area.3) "Walkie-talkies" that are "full power" 5-watt mobiles, generally with cigarette lighter power take-offs for use in cars when not using internal batteries. This is the most common style radio produced in the last six years. We estimate that there are one to two hundred of this and other high-powered mobiles (see type 4) in the RoF.4) High-power mobiles, 5-watt mobile radios designed for use in cars. These and the high-powered walkie-talkies exist in two sub-types: a. AM only. Older CB radios only supported AM modulation.b. Single Side Band capable. SSB gives you basically double the range for the same power. Newer CB radios have a switch that allows them to run SSB.SSB radios have a second advantage in addition to range. They can not be overheard with a crystal radio. AM radios can be eavesdropped on with 17th century built radios. SSB radios have built-in signals security. SSB signals are not understandable without a BFO (Beat Frequency Oscillator) capable receiver, and so SSB is secure except against stolen radios capable of tuning into the 27 MHz band.Having said that, stealing a CB is a possibility, but they also need to steal a battery charger, a generator, a set of batteries, etc., etc. The on-ship radios for the air force and the on-ship radios for the navy are the newer SSB models.CB radio use outside the Ring of Fire area Managing radio outside of Grantville for tactical use by the military is non-trivial. Batteries die, there are no power lines to plug chargers into. Cars with cigarette lighter outlets don't exist. If you and your army buddies go outside the RoF and you want radios to chat among yourself for battle coordination, you have to figure out how to power them. This is tricky.First, just forget solar power, we have no supply of solar cells in Grantville and can not make more. (The Lindsey publications book "Make your own working solar cell" aside, the copper oxide cells that are described produce so little power that a CB radio would require the entire roof of a house papered with them. High output solar cells are many decades in Grantville's future.) Wind, water, steam, and cranks are how we must power electronics outside Grantville.If someone manages to steal an up-time radio, even if they steal a set of batteries and a generator, they will still need to have a person with pretty good electronics knowledge to manage the care and maintenance of that radio and battery and generator. Destroying radios and batteries is just as likely as charging them if you are notvery careful.For those taking radios away from Grantville and from Gustavus Adolphus' Europe, away from steam engines and windmills, the radio heads looked to Australia's native genius Alfred Traeger for a hint. We'll be taking a page from Traeger's book. Here's how you power a radio outside the RoF. and here's one of them in use: Closeup of Traeger Generator: Photo of the woman pedaling the Traeger radio: Battery management is difficult. A car battery lasts about three thousand charge cycles. Even with careful use, the best will die within the next six years. Once we've used up the supply of car batteries, we will be down to wet cells of some sort. Danielle cells, or hand-built lead-acid cells withmuch lower efficiency than what we brought along with us can be made. Danielle cells (wet cells) were used to power the first radios and telegraphs and telephones. They are well doc.u.mented and simple to make, once Grantville begins importing and refining zinc.Hand-held radios will slowly become man-portable and then fixed base operation as the supply of rechargeable batteries declines and Grantville lacks the tech base to make new compact batteries for them. Over the course of the first few years down-time, the battery to run a walkie talkie turns from a few C cells into a couple of three-gallon buckets of blue goo and sulphuric acid.FRS Handheld Radios There will also be a small number of FRS (Family Radio Service) 49 Mhz handhelds which are FM.Gayle used one pair in1633 to chat with Oliver Cromwell in his dungeon. Range isvery limited (less than one mile). Plus, see the battery problem above. Less than 20 FRS radios exist in the RoF, since in 1999 they were not yet popular.Ham Radios You can't talk about Ham Radios without talking about Hams. The 1632 authors are blessed with a good selection of people in Grantville who know about radios, who build, operate, and collect radios as a hobby, and who have the material needed to set up a functioning communications system for the new United States (which, by the end of1633, is now the United States of Europe).In late 1999, there were eighteen amateur radio operators in Mannington, and thus in Grantville. There are three Extra cla.s.s (the highest), two Advanced cla.s.s Hams, five General cla.s.s and one Tech-plus. All those have shown Morse code proficiency. There are five Technician cla.s.s Hams who have shown general cla.s.s knowledge of radio operation and design. There are two Novices. One of the Extra cla.s.s Hams is female.The FCC database does not give information on original date of issue of licenses, but a number of those licensed have licenses dating back ten years, which is the expiration period. Two of the three "extras"must have studied and tested together, because their call signs are sequential.These individuals-not them, of course, but the characters who reflect their skills in the 1632 universe-have a large variety of radios available. Several of those have been sent out with the various diplomatic missions along with antennas and antenna parts to London, to Amsterdam, and (in the upcoming novel1634: The Galileo Affair )to Venice. As follows: Julie and Alex Mackay have a portable Radio Shack DX-398 and a supply of six-volt lantern batteries to power it.]Gayle Mason has three FRS handhelds described above, a Radio Shack DX-394 receiver, and a hand-built CW transmitter and amplifier powered by a set of Traeger pedals. She has an isotron 80b antenna which she hangs out the window of the tower to use.]Rebecca Sterns and her mission were supplied with the best radios of any team in1633 , which makes sense, as sheis Mike Stearn's wife. (And, leaving aside nepotism, her Holland mission is likely to bear the brunt of the relaying work for all the diplomatic missions.) Becky has a Kenwood TS520 transceiver. It is simple to operate, plug and play, 12 V ready, 160M to 10M all band transmitter, SSB, CW, AM capable of operating at either 20Watts or 100Watts. It will "punch through" to Grantville with no problem. In the same box integrated is an excellent receiver, better than the one sent with Gayle for our purposes. Original cost was around $600. Good stuff, two revisions back from the current state of the art. It's bulletproof. It pulls 20 amps at 12V for power, exactly on target for our power budget. It was chosen from the radios available in Grantville because its tube finals will tolerate poorly matched antennas better than an all-solid-state radio would. The Holland team also has an isotron 80b antenna and wire to make a big "beam" antenna if they get a place and the time.Radios have been a.s.signed to the mission headed for Venice also, but as of the time this article was written those stories had not been published and a discussion of their capabilities would give away story elements currently not for publication.Meanwhile, as of1633 , large antenna installations are in place in Grantville, Magdeburg and Luebeck with up-time designed and built "Ham" radios for long-distance use. Due to the Maunder Minimum and the sunspot issues, long distance communications is done via Morse code at 3.5 MHz, and sometimes at 1.2 MHz.Grantville will be building more "Ham" style radios for use by the army, the diplomatic corps, and the banking system. Using recycled parts, and arranging a relay network, Grantville can build between one hundred and several hundred CW (Morse code) radios for this purpose until they get tubes on-line.It is expected that Grantville can start tube production sometime in the late 1630s or early 1640s. (Radio tubes are very hard to make. The characters will have to reinvent a few industries to make tubes. Radio tubes are not light bulbs. They are much harder to make than light bulbs.) Using these down-time-built but up-time-parts radios, Grantville and the USE can have world-wide communications as soon as they can train operators and send them out. The limiting factor on building down-time-built radios is the availability of high power transistors and tubes salvaged from radios and old TVs. It is unclear how many such high-power parts will be available. Transistors have a "top frequency"beyond which they become mostly useless. In order to build high-powered radio transmitters, the techs will need high-power high-frequency transistors and/or tubes. The salvaging of power supplies of dead equipment will be a booming business for a while.Every tube will be cherished.If Grantville was really good at putting its junk into the dump-which, alas, was not within the Ring of Fire and remained behind in the old universe-then there will be substantially fewer high-power radios built, and spark-gap radios will become far more important than is described here.Strategic radio, long-distance diplomatic and military communications will be CW-only (Morse code).This is due to the Maunder Minimum.Additionally, it is presumed that we are not transmitting CW in clear, and that either one-time-pad ciphers generated off the computer screens, or reasonably sophisticated codes beyond manual cracking will be used.However, the number of up-time parts is limited. What can they do, until they get to building down-time tubes, to make new down-time radios?The obvious answer is "spark" radios. Spark existed long before tubes did, and they can and will build spark transmitters and crystal radios.Details about the design and operation of spark transmitters and crystal radios will have to wait for another article. Spark transmitters and crystal radio receivers can be built with 17thcentury ("down-time") resources.Broadcast Radio & TV 1632and1633 depict the existence of TV in Grantville. No commercial radio or TV broadcast facility existed in Mannington in 1999/2000, so it does not exist in Grantville at the time of the RoF. The high school had a TV production studio, but no transmitter. No one had a commercial TV or radio transmitter.The TV "broadcasts" that Rebecca Stearns gave in1632 , and which continue in1633 , are not "over the air" but are rather "cablecast." A link was made from the TV studio in the high school to the "head end"of the cable TV system in Grantville, and shows and movies were distributed over the cable system.There was no "transmitter," no tower, and no antennas were needed.The people partic.i.p.ating in the 1632 Tech Manual conference in Baen's Bar discussed for a long time how to resolve the lack of a commercial radio station in Grantville. The FCC antenna tower database made it clear that no appropriate towers existed in Grantville for an AM radio station. While it would have been possible to build an FM radio station simply enough, you can not hear an FM station on a crystal radio. Since the authors of the 1632 series wanted a supply of down-time radios to be available to listen to the broadcasts of the Voice of America, it was necessary to figure out how to build a radio station.Gayle Mason's Ham radio station could be rebuilt to provide a modestly powered AM radio transmitter, but what to use for an antenna? A natural antenna for an AM radio station is 140 feet tall. The folks in Grantville did not have such a tower, nor did they have the free steel to build one. The available steel was going into the ironclad ships and into railroad track.Additionally, the government of the new U.S. wished to conceal its ability to talk to its remote diplomatic staff as long as possible. After months of discussion on Baen's Bar by the "Barflies," the concept of the Great Stone Radio Tower was born. Many European cathedral towers exceeded the height needed for the Voice of America transmitter tower. By building a stone antenna tower (and running copper wires down the outside to act as the active antenna elements), Grantville solved both the technical problem of building the tower, and the political problem of distracting the French and the English from the ability of Grantville to talk to its diplomats. Somehow the idea that long-distance radio requires huge ma.s.sive antennas became commonplace.By early 1634, the Voice of America will be on the air with a transmitter rebuilt from Gayle Mason's high powered Ham radio transmitter, and the Great Stone Radio Tower.