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Whenever someone starts telling about finding distances in astronomy, it all starts with a parallax. The example they give is straightening your hand and see how your thumb changes its location while you switch your eyes from one to another. How does this work?
What I don't understand: How can you practically in trivial cases (where parallax is significant and easily observable), can you use this to find distances?
For example, assume there is a tower which I can see from my roof: How can I find its distance using parallax? It's about $70-80$ meters from the roof so I think I can get significant parallax if I move across the roof but how to take that angle and how do I proceed then?
First, to measure the angle accurately, you need a point of reference at approximately infinite distance. In astronomy, this is in the form of very distant stars; for your earthly example, perhaps it can be an even more distant building almost on the horizon.
Next, we look at the angular separation between the object with significant parallax, and the object at "infinite" distance, at two different observer locations. We assume the reference object doesn't move at all from our viewpoint as it is so far away. We look at the difference between these two angular separations to deduce the parallax angle.
The rest is just a bit of trigonometry: for the parallax angle $ heta$, you can show easily that $ an heta = d/D$, where $d$ is half of the distance between the two points at which we took the measurements, and $D$ is the distance to that building (or star) we are measuring the parallax of. From this, we can easily calculate $D$.
Note that in astronomy the formula $Dapprox 1/p$ is used instead, where $D$ is in parsecs and $p$ is in arcseconds. This simplification is because of the definition of the parsec together with the small angle approximation $ an p approx p$.
Surveyors do this in their sleep, and have been doing it for centuries. That has been a standard technique for mapmaking until at least the late 20th century (before laser rangefinders, satellites and GPS).
They typically use an instrument called a theodolite for this, which is basically a telescope with crosshairs/bullseye mounted on a leveling tripod, with vertical and horizontal precision angle scales. You might have seen theodolites around construction zones.
If they can, they'll have an assistant hold a graduated staff(1) at the place they want to measure for extra precision. If they can't, they will seek an easily distinguishable feature of the object/place.
Just like in astronomy, in order to make this type of measurement they need a reference landmark to measure the angles with precision. In astronomy we use very distant or “background” stars; in surveying they can use a staff on each of the observing spots as viewed from the other.
You start from one viewing spot, level the theodolite, aim it at the leveled staff placed at the other spot, and write down the angle on the horizontal scale. Then you “sweep” the theodolite until it points at the site of interest, and note the second horizontal angle measurement. Subtract the two and you have the angle at that corner. Notice that you don't even have to align the theodolite with the North. Swap places with your staff, and repeat from the other viewing spot, and you have a second angle. With two angles and one known distance (between the two observing spots, you need to measure that too) you can use use trigonometry (compute the third angle and use the sine law) to calculate the distance to the site of interest. With the coordinates of both viewing spots you even have the full coordinates of the site.
If you can't or don't want to go back and forth for whatever reason, you could use a third object as a reference point. The reference object must be one for which you know the distance and location so you can adjust for the reference's own parallax. The trigonometry is obviously more complicated. Or the reference must be so far away that its own parallax can be considered negligible (like it happens in astronomy with background stars)
Surveyors will often make several measurements from different locations, including previously known and accessible landmarks. These measurements are then chained together, for error correction.
(1) If you can get someone at the spot with a graduated staff, the fastest way to measure the distance is to compare the apparent size of the graduations through the scope against the graduated crosshairs (you must adjust for the vertical angle to the site; the staff is kept vertical with the help of a bubble level so you know the angle); this technique does not use parallax. But you usually can't do this when surveying mountaintops for example. This might also be more demanding on the optics and I don't know when it became feasible.
(*) I studied basic surveying in college but it's been decades. I might (probably) have some details wrong. Hopefully others can chime in if corrections are needed.
How can I find the distance of the tower while standing at my roof? - Astronomy
I've inserted a photo of the tower into an etching by Giovanni Piranesi. His etchings have been my inspiration for this series of Roman molds I'm working on.
Mold #60 contains all of the blocks needed to build this tower. To make this model, you will need to fill the mold 13 times.
Be sure the blocks are completely dry before gluing them together. For detailed instructions on pouring the blocks, see the Casting Instructions Page.
I'm using a special type of casting material for this tower called "dental plaster". To find out more about it, check out the "Casting Instructions" page. It has a greenish cast to it.
The prison tower mold has special blocks with a brick design on one corner. These are specially made to put an alternating brick pattern on the corners of the tower.
If you stack the blocks so the smooth flat bottoms are down, the corner pattern won't work.
At this point I discovered a problem. It appears that the arch pieces are too short and leave a gap under them. After some thorough searching I discovered what the problem was. It also happened to me on the Wizard's Tower's arrow slits.
When you scrape off the blocks (while casting), they end up a little taller than they should. All of my original blocks measure exact within 1/1000th of an inch. But depending on how hard you scrape off the mold, their height can change.
Usually you don't notice it because you build with the flat side of the block down. Since all of the blocks are too high by the same amount, they line up straight. But when you turn a flat block on its side, it doesn't have the height increase and appears short.
Finish out row 11 but do not glue to the blocks that are marked. Go ahead and glue the new blocks to each other though. This will form the next section that will lift off.
Doing this lets you see at a glance where the tower comes apart. This becomes really helpful when we glue the stairs on.
To get the gate to stand up, cut a strip of thin stiff clear plastic about 1/2" wide x 1" long. The plastic I used was from the tab of a file folder.
The small arch (1/4 wide opening) and the large arch (1 1/2" wide opening) are new sizes and don't appear in any other mold as yet.
The rounded arches are very useful. Form a circle with four arches, lay them on their side and you have a round pit in the floor.
Radiofrequency (RF) Radiation: Satellite Dish, Radar, Power Line, and Miscellaneous
The nominal output of these systems is a few hundred watts of microwave power. In general, these systems are not operating when the aircraft is on the ground. However, there may be circumstances, especially during maintenance and testing, that ground personnel may be exposed to the X-band radiation emitted by the system. There is a large database of calculated and measured hazard distances of X-band systems. The power output of weather radar is many orders of magnitude lower than fire control radar. While fire control systems have the potential to overexpose personnel, it is a common misconception that any system found in the radome of an aircraft nose is dangerous.
In the X-band region, the Institute of Electrical and Electronics Engineers (IEEE) C95.1 Radiofrequency Radiation Standard (1999), as well as the American Conference of Governmental Industrial Hygienists, Threshold Limit Value (2000) has an exposure limit of 10 mW/cm2 for controlled (occupational) exposures, averaged over 6 minutes. For uncontrolled (essentially public areas), the IEEE has an exposure limit of 6.67 mW/cm2, with a slightly longer averaging time. Measurements made on a typical WXR-700 system by the United States Air Force in 1996 were unable to produce levels that are above either the controlled or uncontrolled limits recommended by IEEE. Therefore, in general, it is safe to assume that these systems are incapable of overexposing personnel to recommended standards in wide use both in the United States and the rest of the world.
In 1996, the World Health Organization (WHO) established a program called the International EMF Project that is designed to review the scientific literature concerning biological effects of electromagnetic fields, identify gaps in knowledge about such effects, recommend research needs, and work towards international resolution of health concerns over the use of RF technology. The WHO maintains a website that provides extensive information on this project and about RF biological effects and research.
Potential health concerns about power lines were first raised in a 1979 study which associated increased risk of childhood leukemia with residential proximity to power lines. Since that initial study, numerous other investigations have attempted but failed to clarify whether observed associations between electromagnetic fields (EMFs) and various health effects were causal or coincidental. Some scientists have argued the physical impossibility of any health effect due to weak ambient levels of EMFs, while others maintain that the potential health risks should not be dismissed even though the evidence remains equivocal and contradictory.
There are no known health risks that have been conclusively demonstrated in relation to living near high-voltage power lines. But science is unable to conclusively prove that anything, including low-level EMFs, is completely risk free. Most scientists believe that exposure to the low-level EMFs near power lines is safe, but some scientists continue research to look for possible health risks associated with these fields. If there are any risks such as cancer associated with living near power lines, then it is clear that those risks are small.
Your local electric utility company would be the best source of information on what exactly is being installed. Most companies have good information available on EMF facts and can answer questions about local concerns. Look for a consumer-information telephone number in your electric bill.
There are two general sources of information about EMF that you might be interested in pursuing:
- "Possible Health Effects of Exposure to Residential Electric and Magnetic Fields," Committee on the Possible Effects of Electromagnetic Fields on Biologic Systems, National Academy of Sciences/National Research Council.
- An excellent collection of questions and answers on health issues related to power lines from the Medical College of Wisconsin.
The National Academy of Sciences reports of reviews of possible health hazards of power-line EMF are available online. Two reports may be of interest to you: a 1997 Report and a 1999 Report.
The second, most recent, report is available for reading online. It presents a review of the results from the EMF-RAPID (Electric and Magnetic Fields Research and Public Information Dissemination) program, a national research program authorized by Congress in the Energy Policy Act of 1992. In the Executive summary the report concludes (in part): "The EMF-RAPID biological research contributed little evidence to support the hypothesis that a link exists between MF [magnetic fields] and cancer" and "The results of the EMF-RAPID program do not support the contention that the use of electricity poses a major unrecognized health danger."
Ham Radio Tower Types
There are four main types of towers. Each type has its specific installation requirements. Many are available in light, medium or heavy duty.
- Guyed. In terms of "cost per foot", the guyed tower is the most economical. However, you must have enough space for the guy wires!Guy anchors should be installed away from the base of the tower at a distance of between 60% to 80% of the tower height. (Follow the manufacturer's instructions).
When you buy a new tower,
the manufacturer will normally supply detailed installation instructions.
Follow them to a "T"!
Click Here To View
A list of tower manufacturers for ham radio.
Hang 'em High: Options for antennas, masts and towers
First, we should note the difference between antennas, masts and towers. A mast or tower is simply the thing that holds the antenna up off the ground. Masts are usually metal, but under unusual circumstances they might be made of wood or other substances. In FM broadcast, the antenna is usually mounted to the mast near the top. A mast is generally a single piece of pipe, while a tower is a set of interlocking pipes (typically in a triangular configuration) which can be much taller.
One thing that may be confusing is that in AM broadcasting, the antenna and the tower are the same thing - this is because AM wavelengths are so big that they require an antenna the size of an entire tower - so the solution is just to use a metal tower as the radiator. For FM broadcast, the wavelenths are only about ten feet, meaning the antenna can be much smaller. In FM broadcast the only reason to get so tall is so that the antenna radiates from a high up point that has line of sight to more of the terrain around the radio transmitter.
Caution: Starting Small Is Better Than Not Starting!
I know many stations that founder because they wait to build the tallest thing possible to start. In many cases, I encourage groups to go ahead and put up a short pole now, and wait for the big tall tower until later. A very tall tower built from scratch can cost many tens of thousands of dollars and cause many zoning delays.
At Prometheus, we approach the task of getting the antenna high up like community organizers. If, like many of these stations, you have a small core group and not much money, a tower can be a very daunting task. We think it is best to put something quick up with the small resources that the few of you can muster, gain the support of the community and get everyone started doing their show, and then you will have a much larger group to work together to tackle the task of building the tower.
If you are clearing the rooftops of most other buildings around you by at least 20 feet, you will go farther than you expect. That may be enough to get you going and to pull your community in the doors, and you will be amazed by what they might come up with that can save you a lot of headaches!
A few words about limitations on antennas:
Antennas are deceptively simple. On the one hand, an antenna is just a hunk of metal. They are usually somewhere between two and fifteen feet long and two to 6 feet wide on the FM band. On the other hand, they are sort of complicated. They are picky about where they are placed, and what is near them. In radio, everything is different from how regular electricity works. For instance, if you wanted to plug in a lightbulb at the top of a pole, it would not matter if you had a hundred foot extension coiled up for fifty feet and laying in a pile at the basis of the pole. But with radio, that could totally ruin your signal. The elements of an antenna and the transmission line that feeds it need to have a very particular geometry in order to prevent reflections and radiate properly.
An FM antenna should be at least one wavelength (about 12 feet) away from any other obstruction. FCC rules require that a transmitter radiating a hundred watts ERP be at least 13.5 feet away from where anyone hangs out for more than a few minutes at a time.
Locating at a site that has other radio equipment (TV transmitters, cell phone stations, amateur radio equipment, etcetera) often requires a study by a radio engineer to make sure that your new 100 watt transmitter is not the "straw that broke the camel's back" which puts the site over the legal limit for radio radiation exposure to the public.
Another consideration is whether you will interfere with the other equipment, or the other equipment will interfere with you. The engineer who is the manger of the tower will probably be able to make a good educated guess at the potential for interference between the different equipment on the tower. Interference between equipment that operates on different bands is unlikely, but not impossible, especially if some equipment is at much greater power than others and the antennas or transmitters or feed lines are very close to each other.
Low power stations are allowed 100 watts ERP at 30 meters Height Above Average Terrain (HAAT). If your antennas are taller than 30 meters HAAT, then they will have to reduce their ERP to make up for it. The FCC will tell you on your construction permit if you have to do this. If you are shorter than 30 meters HAAT, you do not get to turn up your power to make up for it. You must build no more than 2 meters higher or 4 meters lower than what was stated in your construction permit. If you change it more than that, you must submit a &ldquominor amendment.
What antenna are you going to use?
Probably 75% of low power radio stations will want to use a 150 watt transmitter and a pair of circularly polarized antennas. The antennas will need to be about 10 feet from each other, one directly above the other. The exact number depends upon the frequency at which you will be transmitting. Two circularly polarized antennas have a gain of just about exactly 1db, meaning that if you put a hundred watts of transmitter power (TPO) into them, a hundred watts of Effective Radiated Power (ERP) will come out of them. Low power stations are allowed 100 watts ERP at 30 meters Height Above Average Terrain (HAAT). If your antennas are taller than 30 meters HAAT, then they will have to reduce their ERP to make up for it. The FCC will tell you on your construction permit if you have to do this. If you are shorter than 30 meters HAAT, you do not get to turn up your power to make up for it. You must build no more than 2 meters higher or 4 meters lower than what was stated in your construction permit. If you change it more than that, you must submit a &ldquominor amendment. &ldquo
Another common option is to use a single circularly polarized antenna. A single circularly polarized antenna has a gain of &ndash3db, which means that if you put 100 watts TPO into it, it performs as __ watts ERP. That sounds bad, right? But actually it is good, because the ERP only counts the horizontally polarized part of the signal. The vertical part of the signal is not counted, so you "get it for free." so you are allowed to put about 250 watts TPO into a single circularly polarized antenna, and it is considered to be 100 watts ERP. But of course, the vertical signal is still going out and giving signal to your coverage area. Using one bay with 250 watts or two bays with a hundred watts is almost exactly the same in terms of coverage.
A 300 watt transmitter ($4500) plus a single antenna ($200) could cost you $4700). A 150 watt transmitter ($2500) plus a two bay antenna system ($700) would cost about $3200. And the monthly power bill will be about half the size for a 150 watt transmitter. But in some cases, if the property owner or the zoning commission will only allow you to put up one discrete antenna that is only a few feet in size, this single circular polarized antenna option might be better for you.
Typical circular polarized antennas weigh about 7 pounds a piece, and present a windload to the tower of about 8 pounds.
Antenna pole on top of tall building:
The best solution is to have a structure that is already tall, since making tall things from scratch is usually an expensive pain in the neck. Look around for church steeples, water towers, old ham radio towers, bridges, billboards&hellipanything tall. The best solution is if you can put a fifteen or twenty foot pole on top of something that is already tall.
Ideally, the antenna should be about one wavelength (eleven or twelve feet) from any other object (except for the pole it is mounted to). There will be reflections even off of a slender pole, and radio energy will be dampened in the direction of the obstruction.
One very simple but sort of expensive solution is what's called a "non-penetrating roof mount". These mounts can support a ten foot pole, and are held down with cinder blocks. They are very heavy, so you might want to find a local supplier. They generally cost $100-$150, not including shipping.
Radio shack also has a nice selection of clamps and poles that can attach to chimneys, that can drill straight into the roof with bolts and roofing tar,
They do not always stock all these things, so it is best to buy or order a week or two before your project.
Cheap Telescoping Masts
The most common solution for radio pirates has been the 36 foot telescoping mast from radio shack. This is a decent solution for many low power stations that want to get on the air quickly.
You can count on spending a few hundred more dollars on turnbuckles, guy wires, hardware for mounting and so on.
If you drive through town, you will see dozens of these on your neighbors roofs holding little satellite dishes. Some towns require a permit for these, though I have built at least ten of them and never gotten a permit and never had a problem because they are so common.
Be sure to do a good job roof at the base, and make sure the roof underneath is solid. You may want to build a little platform of solid 2x stock for a few feet, bridging from rafter to rafter under the base of the mast or tower, and then roof over it before putting the mast on top. For mounting points to attach the guy wires, I have bolted 2 foot 2x 8s to the underlying rafters, screwed in a big screw eye, and then roofed over the whole thing except for the screw eye. I have also used clamps attaching to iron vent stacks, chimneys and other solid roof objects to attach to.
At the base. I usually extend the whole pole horizontally and lock it in place on the ground or roof surface, so you should make sure you have room and think about which way you want to lay it so you can control it. It is also possible to extend the pole one section at a time vertically in place while controlling it with guy wires, though I have found this more difficult and prefer tilting up.
A rule of thumb says that you need twice the height of the pole in distance from the base of the pole to any power lines. Survey the area carefully so that if the pole ever were to fall, it would not hit a power line!
Another rule is that you should have tie points for the guy wires in three equally spaced directions, at 60% of the total height of the pole. For a 36 foot pole, that would be about 20 feet. You can fudge this a little bit to fit on your roof, but not too much!
The instructions say that you are supposed to put a set of guy wires every ten feet. Maybe I am a bad person but I usually don&rsquot really do this. I have generally found two sets of guy wires adequate on a 36 foot mast. Be careful about tightening down super hard, people have actually driven their poles through the roof by clamping down too hard with the turnbuckles! Everything should be tight, but don&rsquot go crazy.
I have never done a 50 foot telescoping mast. Something that tall is more likely to attract attention than a 36 foot pole, which almost everyone has. With 50 feet, I would not cheat on the number of guy wires or the spacing. With a 50 foot pole on the roof, I think it would be much more likely that someone would notice, so you really might not be able to slip by without a building permit at that height.
"The chance of that is less than getting hit by lightning!&rdquo
What are the chances that your tower will get hit by lightning? Not bad, actually- remember that the chance of getting hit by lightning is sort of absurdly small when you are on the ground, but as you get to be the tallest thing for a few thousand feet around, your chances get much higher. I know two small stations that have gotten hit by lightning.
All antennas must be grounded. Usually the metal mast or tower acts as the ground, but if it is not planted firmly in the earth (as in it is mounted on top of a roof) you must run a big fat ground wire (at least __guage) down to the earh, and attach to an 8foot antenna grounding rod driven deep into the ground, with just enough sticking up to attach the thick wire to. The griound wire should be as short and direct as possible, and the bends should be as smooth and gradual as possible. Lightning will aways take the most direct path, and you want your groundwire to be that &ldquopath of least resistance&rdquo (yes, that is where the expression comes from). A further consideration is that the pole itself should be at least 3 feet taller than the top of the antenna that is mounted to it. This is necessary for lightning protection.
A very simple, common option for LPFMs is the radio shack 36 foot telescoping mast, available for about $60 from a local radio shack. With all the appropriate guy wires , turnbuckles and other hardware, installing this mast costs about$200 and can be done in an afternoon with 5 or 6 people helping out. They can be installed on the ground or better, on top of a building. To add stability, it is good to get a tripod or a heavy duty section of mast for the bottom. You will need guy wires, which will need to be anchored to the roof or the ground at a distance of at least 60% of the height of the pole, spread out as equidistantly as possible in usually three but occasionally 4 directions.
Easy for a town. Road or railway right of way Utility poles are made of wood, fiberglass, or steel. Each have their advantages. The general rule for poles of any sort is that they should be buried in a hole in the ground that is ten prevent of their length, plus two feet. Some poles have holes already built in to them for steps. Installing a utility pole generally requires a permit. Utility pole manufacturers are not accustomed to selling single poles, and shipping is a big pain in the neck, so it is best to go local. If you are in a small town, a friendly call to the highway or streets or electric department might find you a used one, or they could tack on one for you on their next order without too much problem.
There are a few approaches to water towers. If possible, the best thing to do is to mount a pole to the top. Often historical and aesthetic concerns preclude this option. The next best option is to buy 4 panel antennas, which would be located at equal intervals around the side of the tower. This is a fairly expensive, but effective solution. Another solution would be to mount circularly polarized antennas on the legs below the water tank. This will cause some distortion of the coverage pattern, but may not be so bad.
Building a tower can be quite a project. Finding a suitable site can be difficult. Your low power FM equipment will probably be fairly light and not subject to a lot of wind loading unless you are installing some sort of solid dish. So unless you plan to rent the tower space to others (which can be quite lucrative, but nay not be the business you thought you would find yourself in), you can use a fairly light duty ham radio tower. Rohn towers has a great catalog to give you a sense of what is out there.
You need to be able to get at the antenna to make occasional adjustments. It is cheaper to put up a fixed tower, but one that you can raise and lower may be a good investment if you have to work on it a lot.
Is it climbable? Towers that can support human weight up at the top are definitely a bit more complicated than your basic antenna pole.
Is the tower site accessible to a crane or a cherry picker?
Many counties across the country have moratoriums on the construction of towers, but there are few places that would prevent the erection of flagpoles.
In Maryland, the owner of the property where we wanted to build set our transmitter was not interested in having a big ugly tower built on his property, but was thrilled at the prospect that we would install an 80 foot marine flagpole with yardarms and a place to hang the American flag and the flags of the local football and baseball teams. Similarly, the county refused to even consider a tower, but let a flagpole of similar size through in just a few weeks.
Trees have been known to work. There are some stations that have installed antennas in the tops of trees. A few issues come into play. One is the proximity to the leaves of the tree. Antennas work best when they clear any other object by at least a wavelength or two, which in FM is 20 to 24 feet. Leaves, particularly, have a lot of water and a lot of reflective surface, and can significantly throw off the tuning of your antenna. If you use a tree, you will have to make an alternate arrangement for grounding, since the tree itself will not conduct electricity to ground like a metal mast would.
Renting tower space
Many wireless towers are owned by companies that would be happy to trade extra space on their tower for monthly rent payments.
Other options for stealth:
Because of the proliferation of cell phone towers and public concerns about radio radiation health effects, companies have in the past few years come up with a number of &ldquostealth&rdquo antennas, which fit inside flagpoles, fake palm trees, look like giant cactuses, etcetera.
High gain for low power operation
If you are planning to build at a remote location far from available utility power, you might consider a high gain antenna, which puts out more &ldquoeffective radiated power &ldquo (ERP) than the actual Transmitter power output (TPO). A smaller amplifier can be used, allowing a relatively small solar and battery installation to power it. A good antenna for this sort of application is &ldquoThe Comet&rdquo costing about $100 from companies like Progressive Concepts.
Battle of the Astronomy Tower
The Battle of the Astronomy Tower, ΐ] also known as the Battle of the Lightning-Struck Tower, was the second major conflict of the Second Wizarding War. It took place in the topmost part of the Astronomy Tower, a few corridors of the 7th Floor, the Marble Staircase, the Great Hall, the Entrance Hall, and the grounds of Hogwarts School of Witchcraft and Wizardry, in the mountainous region of Scotland, Great Britain on the evening of 30 June, 1997. Ώ] Α]
Lord Voldemort secretly organised the attack by ordering sixteen-year-old Death Eater and Hogwarts student Draco Malfoy to assassinate Albus Dumbledore, the only wizard in the world who Voldemort feared. Although his previous attempts at assassination had failed, Draco managed to sneak a number of Death Eaters into Hogwarts via a pair of Vanishing Cabinets in the Room of Requirement, and they encountered a number of Hogwarts teachers, students, Dumbledore's Army members, and Order of the Phoenix members, who had been standing guard at the school at the request of both Dumbledore and Harry Potter. As the Order of the Phoenix and the Death Eaters battled, Α] Severus Snape killed Dumbledore, Β] an act that was later discovered to have been secretly planned between Dumbledore and Snape, as Dumbledore would soon afterwards still have died after putting on Marvolo Gaunt's cursed ring, which was a Horcrux, and was afflicted with a deadly curse that would have eventually killed him anyway. Γ]
Climbing Durham Cathedral Tower
There’s a university-wide superstition that if you climb the Durham Cathedral tower before you graduate, then you won’t graduate. This belief has existed for many years, and so a tradition was formed which led to hundreds of students climbing the tower in the week following their graduation. I, too, planned to save this experience until the summer of my BA graduation in 2017. But then in 2015 Durham Cathedral gained a hat of scaffolding, the tower was closed, and my post-graduation hike of its 325 steps was thwarted, as were the plans of many Durham graduates.
But finally, after four years of anticipation, the tower has been re-opened. As of June 1st 2019, the Cathedral no longer has a white hat covering its beauty. Students are free to climb to their heart’s content! And while I may still be at Durham as a PhD student, my post-BA and -MA graduation climb was awaiting — I just hope the superstition doesn’t prove true for the outcome of my PhD.
So on Monday of this week, I followed Eleanor up the winding spiral staircase. I huffed and puffed up every step, and walked out onto the roof of the Durham Cathedral tower to see a stunning, sunshine-filled sight.
Stunning views across the Durham countryside
Durham Cathedral is the centre of Durham. It is the highest building in the city, dwarfing the castle to an almost unnoticeable size. No matter where you are, you can see the top of Durham Cathedral popping up in the distance. I moved to Durham in September 2014, and I spent the next five years walking around the city, seeing this impressive monument from (nearly) every angle. On Monday I got to see it from above, standing atop this monolithic object on the Durham skyline. After spending so much time staring up at it, I now found myself stood atop this amazing building. I looked out onto the city in which we became adults, trying to spot all the Durham places full of memories where the Cathedral always hovered in the background.
There was the DSU, the Durham Students Union with its ‘interesting’ architecture. Turning to another side of the tower, we found, in the vague distance, our student house from second year, and from a different angle, my houses from third and fourth year. From another, we could spot the university library filled with the books I cited in my essays, and the college we both hold dear was peeping up above the trees on the hill. And there was the hill where my husband proposed to me, with Durham Cathedral in the background. Looking out onto this city, I realised how many memories this place holds for me, after only five years. I looked out onto the city which has shaped how I think and live, standing atop its most memorable object.
It seems a bit unfair to call Durham Cathedral an object, but it is one — just a very big one. And it is an object which means a lot to me, not just in its beautiful architecture or its imposing presence. I remember that I always planned to take the time to wander in, sit in a pew, and have some quiet time, maybe draw or write a little something. I never did, but I guess there’s still time during my PhD years. I did matriculate three times in this cathedral, and I have graduated twice. I attended Sunday morning matins in my last year of living in the city, making the cathedral a little more dear to me from a spiritual point of view. I took part in the BBC Radio Four Christmas broadcast, recorded in Durham Cathedral in 2016. I have sat on the grass outside in the sunshine, and I have stood amongst the hundreds of graduation guests as camera upon camera was pointed up at the tower.
Can you spot Hatfield College and the DSU?
The tower on which I stood, and which is now another place of significance for me in Durham. The Cathedral has been standing for nearly 900 years, and my mind expands in wonder at the millions of memories it must hold. But it will always hold a special place in my heart for the memories of mine which it contains, memories which I’m reminded of every time I’m on the train to Durham and I spot this impressive building getting ever-closer.
When I bought my tower-climbing ticket I wasn’t expecting such deep thoughts to emerge. I expected to be out of breath at the top, my heart racing, from the physical exertion of climbing so high. I expected to be stunned by views across the rolling lands of Durham County. I expected to enjoy the breeze and play spot-the-place in Durham City. But I hadn’t expected to grow so thoughtful while standing so high in the sky, looking down on the city which has welcomed me, educated me, and provided me with a second home — one with an awe-inspiring Cathedral at its centre.
You can read more blogs from me at Object Blog
Iconic view of the Cathedral from Durham Railway Station
At the heart of every successful radio installation is the antenna support structure, because there is no substitute for a radio antenna that has sufficient height! That is why DX Engineering offers easy shopping of an extensive selection of towers, masts and accessories with super-low freight costs that lead the industry. Choose from free-standing, bracketed or guyed tower packages and components from ROHN Products, American Tower Company, TBX and more. DX Engineering stocks a huge supply of Phillystran guy lines, grips and a wide variety of tower guying hardware. We have many other tower sections, parts and accessories, including short and hinged tower bases, wall mounts, guy anchors, accessory shelves, thrust bearings and unique tower side mounts, to name only a few. DX Engineering stocks our own exclusive 2 and 3 inch O.D. ultra-high strength 4130 Chromoly Steel Masts for large rotatable directional antennas. For smaller antennas and budgets, we have the tripods, masts and wall brackets that can also help get your antenna “up there” and on the air. For the best selection of antenna support options with super-easy, online ordering, shop DX Engineering.
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Can Setbacks Be Removed?
When the zoning authorities impose setbacks, it is difficult to remove them. When you buy a property that already has setback restrictions, you are bound to abide by those restrictions.
There are instances where property owners want to move back the property line to accommodate a new structure or include a building. In such circumstances, you have to apply and obtain a permit that allows you to adjust the property line.
There are also circumstances where a property owner can request a variance of the setback requirement. A variance is a means, by which the authorities permit the exemption from the requirements of the zoning codes,
Using and moving
Make sure everyone involved is aware of, and follows, these simple rules:
Never use a tower:
- in strong winds
- as a support for ladders, trestles or other access equipment
- with broken or missing parts or
- with incompatible components.
When moving a tower you should always:
- reduce the height to a maximum of 4m
- check that there are no power lines or other obstructions overhead
- check that the ground is firm, level and free from potholes and
- push or pull using manual effort from the base only.
Never move a tower while people or materials are on the tower, or in windy conditions.