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Click for more detail... MAIN STATION LOCATION ADDITIONAL CALLSIGN M3OOO **** E-MAIL: m1ooo@wykeradio.org **** Check out Local Webcam 360° panoramics QSL **** DIRECT ONLY (SWL REPORTS APPRECIATED) **** Self Addressed Envelope + your card to PO Box above.
Combine a visit to the Observatory with two other fascinating local attractions: Beer Quarry Caves and the Donkey Sanctuary, both within 3 miles of the Observatory. Clickable links at bottom of page.
MAIN RADIO AMATEUR STUFF ⅓ PAGE DOWN SPACE NEWS
JUPITER can be seen due South, 40° above the horizon, from 17:00hrs UK clock time - you can't miss it, it's by far the brightest object in that location, despite being 610 million kilometres (377 million miles) from Earth, four times further away than the Sun. With a modest telescope or binoculars of 15 to 20x magnification you can pick out up to 4 of its moons. It's the largest planet in our Solar System and acts as the Solar System vacuum cleaner, hoovering up most of the bits of debris coming our way. Its latest hoovering job was to attract a large comet/asteroid, the size of several football fields, onto its surface on July 19th, with a force thousands of times more powerful than the impactor that exploded over the Siberian Tungusta River Valley in June 1908. Jupiter is a gas giant and we see it by the reflected light of our Sun. This reflected light takes 34 minutes to reach Earth. The reflected light we see actually left our Sun 76 minutes earlier. If Jupiter was just that little bit larger it would ignite and become our second Sun. Fortunately for Earth, it has not!!
On May 31st 2009, evening sky watchers in northern Poland were dazzled by a bright flash of light. A meteoroid of unknown origin hit Earth's atmosphere and exploded. "It was a huge fireball, probably brighter than magnitude -13," Gniewowo resident Przemyslaw Zoladek stated. "The explosion occurred at 20:48 UT and was observed by many casual witnesses and at least two Polish Fireball Network video stations." No one knows if fragments of the object reached the ground. An automated camera in the town of Gniewowo captured a snapshot of the event. video ASTEROID IMPACT ***** ASTEROID 2008 TC3 hit Earth at 0243 UTC 7th October 2008 and exploded in the atmosphere over northern Sudan. An infrasound array in Kenya recorded the impact. Dr. Peter Brown of the University of Western Ontario has inspected the data and he estimates that the asteroid hit with an energy between 1.1 and 2.1 kilotons of TNT. Most of the 3-metre-wide space rock should have been vaporized in the atmosphere with only small pieces reaching the ground as meteorites. No pictures of the fireball have been submitted. The impact occurred in a remote area with few and possibly no onlookers capable of recording the event. So far, the only report of a visual sighting comes from Jacob Kuiper, General Aviation meteorologist at the National Weather Service in the Netherlands: "Half an hour before the predicted impact of Asteroid 2008 TC3, I informed an official of Air-France-KLM at Amsterdam airport about the possibility that crews of their airliners in the vicinity of impact would have a chance to see a fireball. I have received confirmation that a KLM airliner, roughly 750 nautical miles southwest of the predicted impact position, observed a short flash at 0243 UTC, just before the expected impact time 0246 UTC. Because of the distance it was not a very large phenomenon, but still a confirmation that some bright meteor has been seen in the predicted direction”. The position of the aeroplane (+) and the predicted impact area in Sudan (0) can be seen here: ASTEROID 2008 TC3. ASTEROID 2008 TC3 was discovered 24 hours earlier by astronomers using the Mt. Lemmon telescope in Arizona as part of the NASA-funded Catalina Sky Survey for near-Earth objects. Asteroids the size of 2008 TC3 hit Earth 5 to 10 times a year, but this is the first time one has been discovered before it hit. View pre-impact image by Paolo Beltrame of CAST Astronomical Observatory, Talmassons, Italy, here. Remnants of this Asteroid found in Sudan Desert 2008 WAS JUST A SECOND LONGER
DOES SPACE HAVE AN ODOUR? Most people might think that since space is, essentially, a vacuum, it would not have an odour, but according to NASA and its astronauts it does! When the internal airlock door of the International Space Station (ISS) is opened, an odour best described as a “sweet metallic smell, similar to arc welding fumes” is detectable on the astronauts’ suits, helmets, gloves and tools. Similarly, Apollo astronauts reported their Lunar Module cabin smelling mildly of spent gunpowder after a moonwalk, almost certainly the scent of moondust. Steve Pearce of Omega Ingredients, Ipswich, England, has been commissioned by NASA to recreate the odour of Outer Space in order to add a whiff of realism to their astronaut training sessions. Steve says, “NASA wants to make their training sessions more realistic, so when astronauts are simulating a space walk by floating in a swimming pool, their air supply will smell of Outer Space!”
RADIO AMATEUR STUFF M1OOO INTERESTS: ASTRONOMY / RADIO AMATEUR / POWER BOAT RACING / BUSHWACKING (HILLWALKING) / MARINE SEARCH & RESCUE (Rtd). My primary hobby is Astronomy and I am an Astronomy Presenter at the Norman Lockyer Observatory, Sidmouth, Devon. Please note I have no connection with the amateur radio group which meets at the Observatory (I have different radio interests). SPECIAL CALLSIGNS OPERATED: GB400IYA GB0MBS GB0MPB Read report on successful 1st Trans-Atlantic 3.7MHz (80m) /100W contact using the G7FEK Restricted Space Antenna both sides of the Big Pond here Got Local QRM? Check out QRM possibilities
IARU LOCATOR: IO80HP **** WAB SY08 LAT 50°36'42"N (50.61°N) - LON 03°25'51"W (-3.40°W) EXMOUTH WEBCAM **** Location on MULTIMAP **** AERIAL PHOTO **** GOOGLEVIEW WORK ALL PHONE FREQUENCIES 1.8MHz - 1300MHz HF: KENWOOD 450S + ICOM 706MK11G **** Nested ½ wave dipoles **** HOME and /P ARE ATU-FREE ZONES!! **** See at bottom of page for details of my favoured antenna. VHF/UHF: ICOM IC-E90 HANDIE-TALKIE + KENWOOD TH-D7 H/T LOCAL REPEATERS MONITORED: TORBAY: GB3TR 145.650MHz / EXETER: GB3EX 433.000MHz LOCAL ECHOLINK VIA RF EXMOUTH: MB7IEX-L 145.2375MHz / 107.2Hz (Node 297014) EXETER: M0KFW-L 430.0500MHz / 94.8Hz (Node 67174) **** M0KFW-L TORBAY: MB7ITB-L 145.2875MHz / 77Hz (Node 257017) LOCAL IRLP VIA RF TORBAY: GB3TR (Repeater) 145.650MHz / 94.8Hz (Node 5582) HOME CLUBS: SIDMOUTH OBSERVATORY **** WEYMOUTH **** WYKE REGIS MY FAVOURITE HF ANTENNA IS THE HALF WAVE, centre-fed horizontal dipole. For low noise, RF efficiency and sheer simplicity, you can’t beat it! Especially as you can make it for a fiver (£5 / $8US) or less. Just use the following formulae to calculate the length of each dipole leg: FOR HORIZONTAL: 71 ÷ frequency in MHz = length of each leg. FOR INVERTED V: 68 ÷ frequency in MHz = length of each leg. EXAMPLE FOR 3.5MHz (80 METRE) BAND (phone), centre of Band is 3.700MHz HORIZONTAL: 71 ÷ 3.700MHz = 19.200 metres (rounded) for each leg. INVERTED V: 68 ÷ 3.700MHz = 18.400 metres (rounded) for each leg. Your final leg length will vary depending on location, type of ground, height above ground, proximity of buildings, etc., but you’ll be very close with these measurements. TIP: Start off with each leg at 20metres length and shorten to the desired length by simply doubling back and twisting excess wire onto the leg, leaving a small loop where you attach your nylon cord/rope or other non-conducting material for securing the legs to the wall/fence/ground. That way, if you move location, it’s easy to readjust the leg lengths to suit. ** Bish Bosh, Wham Bam Thank You Mam, Job Done. It’s as simple as that! ** AND ALL WITHOUT AN ATU. The centre of the dipole (feedpoint) will typically exhibit between 40 and 70 Ohms impedance, a nice match for your tranceiver’s 50 Ohm output, with a good swr bandwidth of 1:1.6 or less. Incidentally, RF prefers working in antennas measured in metres rather than old-fashioned feet and inches, that’s why you’ll get out better!! And to help you further, ALL tape measures automatically come with dual metric/imperial scale, and metric is so much easier to use, contrary to what most G3s and G4s say!! Q.E.D. (Joke). RULE OF THUMB: The higher the dipole feed point and the higher you get the ends of the legs, the longer the leg length. Conversely, the lower the dipole feed point and the lower the legs (i.e. “inverted V”) means shorter legs. If the feed point (centre of dipole) is freely suspended in mid-air (i.e. no support at the centre), all well and good, but if you suspend the feed point using a metal mast, keep the feed point minimum 100mm (4") away from the mast. Better still, have the top 600mm (2ft) of the supporting mast in non-conductive material such as fibreglass or wood. In practice, most Amateurs can usually only manage to get the feed point 9metres (30ft) above ground level. This is fine and will give an average to high angle of radiation. Lower than this, the radiation angle increases, higher than this and the radiation angle is lower. It therefore follows that if you want to get out further, AND have a more efficient antenna, then height above ground is the answer. I use RG58 coax, and tape 6 turns x 100mm diameter loops of the coax right at the feed point to act as a choke. Use a 1:1 balun if you want – I don’t. I use ordinary electrician’s 7-strand insulated 1.5mm copper cable, which I purchase in a 100metre roll for about £12 ($17US). Don’t worry that the cable is insulated and that you will be doubling back the cable onto the leg to make any final adjustment – the insulation is transparent to the RF energy due to the “skin effect” of the RF, i.e. the electrons run along the surface of the cable, not within the cable, therefore the insulation is ignored by the electrons. EXAMPLE FOR 7MHz (40 METRE BAND) (phone), centre of Band is 7.120MHz. HORIZONTAL: 71 ÷ 7.120MHz = 10.000 metres (rounded) for each leg. INVERTED V: 68 ÷ 7.120MHz = 9.600 metres (rounded) for each leg. TIP: Start off each leg at 10.5metres length to give room to play with, doubling back any excess onto the leg. A FURTHER TRICK: If you want more than one band, “nest” 2 or more dipoles from a single feed point, fanning each band away from the feed point like a "maypole", or by fanning out in the same plane by progressively dropping the legs of each band into a fan-shaped inverted “V”. A single feed of RG58 coax is all you’ll need back to your transceiver and you’ll be able to change bands at will, since there is no ATU (IMU) involved!! NOTE: If you nest a 7MHz antenna with a 3.5MHz antenna, you will probably need to extend the length of each leg of the 7MHz antenna by approx half a metre (500mm). It is also likely this combined antenna will resonate quite nicely on the 21MHz band without an ATU. RESULT! Three bands; NO ATU!!
QUESTION: So why don’t the Amateur Radio books make it simple like that? ANSWER: Because many authors are so full of their own C**P and self importance and have just plagiarised (copied) formulae, theory and dogma from old Stone Age Radio publications and have never heard of KISS – Keep It Simple, Stupid !! Or maybe they have shares in an ATU factory!! The G5RV is a VERY popular antenna. Why? Because Amateurs, particularly when new to the hobby, are sold the idea that for £30 + a £200 ATU they get a multiband antenna system, which is sort of true. Well, as shown above, for £5 per band you can make your own multiband antenna WITHOUT having to buy an ATU. With the £200 or so you've just saved, you are better off buying an MFJ Antenna Analyser which will let you SEE how well (or not) your antenna is performing and allow you to make any necessary adjustments. If you have enough room for a G5RV (31 metres long), then surely you can find the room to squeeze in a 3.5MHz (80 metre) dipole (38 metres long) - even if you have to vertically dangle the last 3½ metres of each leg. The golden rules are: (i) as much copper in the air as possible, (ii) as high up as possible and (iii) swr of 1:1.5 or better – WITHOUT AN ATU! So let’s, once and for all, banish the G5RV to where it rightfully belongs and, if you are lucky (or you know what you are doing), it can be made to work without an ATU, where it has some dBd gain and where it was intended to be used by its clever designer, Louis Varney – the 14MHz (20 Metre) Band! R.I.P. If you must use a G5RV and actually work 3.5MHz (80m) band more than 14MHz (20m), then take a tip and analyse/trim it best for 3.5MHz (80m). This will result in the G5RV not being at its best on 14MHz but, hey, unless you are turned on by filling up your logbook with meaningless 20-second contacts with 5&9 crazies, your signals will be improved on the ragchew band. And Please, Please, stop referring to a “Half-Size G5RV” – there is NO such thing. It’s a bastardisation of the G5RV that kinda works on the 28MHz (10 metre) band, and which you might be able to squeeze onto the 7MHz (40 metre) band with your beloved ATU – but remember, your ATU doesn’t miraculously tune your antenna, it only MATCHES (transforms) the impedance of your antenna (+ transmission line if your ATU is back in the shack) to your radio’s 50 Ohm output. A c**p antenna is still a c**p antenna, whether or not you use an ATU!! STOP PRESS. Carolyn G6WRW has just published an excellent pdf based on the same design as my nested dipole article above. Well done Carolyn. Carolyn's article can be found here. Another excellent article I have found by Malcolm G3PDH on the InterNerd is here. ONLY GOT A SMALL GARDEN? ***** For an alternative and very interesting and easy to construct multiband antenna, you might like to consider the G7FEK antenna. This antenna is a 2 x 1/4 wave element nested Marconi. I regularly copy Mike G7FEK when he's using this antenna on his sked nets when I'm away in the Middle East where it’s difficult to obtain an Amateur transmission permit (I use a palm-size shortwave receiver with its own whip antenna). His signal is consistently good and I reply by cellphone txt, with G7FEK relaying my comments into the Net. This antenna only requires 15m (50ft) of garden!! And it will work well on several bands without an ATU (IMU). ***** G7FEK Antenna details can be found here. STOP PRESS Read report on successful 1st Trans Atlantic G7FEK to G7FEK 3.7MHz (80m) 100W contact here THE TRUTH ABOUT ATUs (OR WHAT YOUR INSTRUCTOR NEVER TOLD YOU) The acronym ATU (Antenna Tuning Unit) has been used by manufacturers and suppliers for years to con the unsuspecting Amateur into believing the unit will TUNE his antenna, which it won't. It should correctly be referred to as an IMU – Impedance MATCHING Unit - which is all it does. An ATU (IMU) will only match your antenna impedance (and transmission line if included) to the 50 Ohms of your transceiver. Your antenna is NOT tuned and remains MISMATCHED to the BAND. On a final note, this time relating to internal AUTO ATUs found on many modern transceivers. Many of these AUTO ATUs are NOT designed to be used on an antenna and feedline of more than 150 Ohms impedance (1:3 SWR), so DON’T attempt to ATU (IMU) high impedances unless you want to store up future repair bills. Most of these AUTO ATUs are NOT designed to handle several hundreds of Ohms, and you will get a hefty bill and a note back from your repairer to advise you NOT to use the AUTO ATU on high impedance antenna systems, typically those antennas sold as multiband. If in doubt, read your radio’s destruction book, although some manufacturers have naughtily left this information out, or at least remain vague, since it undermines the manufacturer’s “unique selling point” of having an AUTO ATU. Again, the uninitiated, beware!!
When you see the Light and your station becomes an ATU-Free Zone, let Mike (G7FEK) and I know and we will be pleased to add you to our list of Amateurs who operate this way. Happy hunting. BEWARE - GO NO FURTHER UNLESS YOU WANT TO READ MY RADIO AMATEUR RANTINGS!! CAN ANYONE PLEASE EXPLAIN TO ME WHY so many Amateurs still refer to the Amateur Bands in METRES! I can’t remember the last time I saw a radio calibrated in metres. Let’s put this archaic practice to bed once and for all and refer to the Bands in MHz, as does the UK RSGB. And why do some Amateurs call "CQ 80, CQ80" "CQ40, CQ40" etc. when anyone on the receiving end knows they are on "80" (3Megs) or "40" (7Megs) etc. anyway? Weird. THE POPULAR AMATEUR BANDS IN MHz: 1.8 3.5 7 10 14 18 21 24 28 50 70 144 430 And I’ve also lost count of the times that visitors to Amateur Radio Stations have left, having been totally confused by the ridiculous Amateur jargon they hear on air – words like QTH, Fine Business Old Man (can anyone please tell me what that means?), HI HI, XYL, Catch you further down the Log, QRZ, QSL, Back she comes to you (again - what's that supposed to mean?) and "the name would be David" - which begs the question what would the name be if it wasn't David! Why not just simply say "My name is David"! Worst of all is “You’re 5 and 9”, where the radio operator doesn't even adhere to the proper 5&9 Code, making the report meaningless anyway. And these Amateurs have the audacity to criticise the jargon on CB Radio!! What’s wrong with using plain language? And talking more than just about the weather and their equipment? I suppose it all helps to mystify Amateur Radio. But surely, in this modern age when we are competing with easily accessible communications (mobile ‘phone, txt, SMS, e-mail, Skype, Internet, etc.) and are trying to attract newcomers, we should be demystifying the hobby. It’s a sad reflection that many visitors to shacks are bewildered when they are confronted, typically, by the back of the head of an old man talking gobblygook down a microphone. So, my plea is – less of the jargon, more conversation in plain language (NOT “This is Mexico One Canada Washington Honolulu” – what’s wrong with “Mike One Charlie Whisky Hotel” as recommended by the FCC, RSGB and the UK OfCom Licence Document) and using NATO phonetics that the general public have been used to hearing for YEARS on TV and films. Another example of our fixed and archaic ways, maybe? By the way, you can always tell when an operator has run out of conversation or has become fed up with his contact with you - he has "suddenly been called away by the XYL" or "someone is at the front door" or "the dog is calling for his walk" despite him having called CQ just 4 minutes earlier! And why do so many Amateurs insist on giving their callsign at the beginning and end of EVERY over? (some contacts and "nets" can appear at times to consist almost entirely of callsigns alone!!) In normal conversation it wouldn’t be done, so why on air? Another mystification? And please stop referring to yourself as WE - there is only one of you!! R AND S REPORTS - THE TRUTH Contrary to the popular belief of MOST Radio Amateurs, R AND S REPORTS HAVE ABSOLUTELY NOTHING TO DO WITH THE READOUT ON YOUR RADIO. The R and S Code is shown below and is related to what you hear: R - READABILITY R5 Perfectly readable R4 Readable with practically no difficulty R3 Readable with considerable difficulty R2 Barely readable, occasional words distinguishable R1 Unreadable S - SIGNAL STRENGTH S9 Extremely strong signals S8 Strong Signals S7 Moderately strong signals S6 Good signals S5 Fairly good signals S4 Fair signals S3 Weak signals S2 Very weak signals S1 Faint, signals barely perceptible So there you have it; R and S should only be given using the above list. By all means quantify the amount of RF being received at your station by reading from your S-meter, but even that is arbitrary and depends on whether your S-meter is reading correctly and whether its reading is enhanced or reduced by your use of pre-amp or attenuation. Using the S-meter for RF reports is pretty meaningless unless you KNOW your meter is set up correctly. Don't be surprised if you give someone a 5 and 9 report, then look down to your readout to see the S-meter showing 7! Or giving a 5 and 7 report, then look at your meter and see 9! Don't be the same as the 5 and 9 crazies that dominate the bands during contests who continually have to request repeats of callsigns, even though giving 5 & 9 reports!
RF VIA ECHOLINK / IRLP Some Amateurs claim it's not real radio when EchoLinked / IRLP repeaters and gateways are used via RF. Well - think about this; it’s not really that different from using conventional RF vhf/uhf repeater systems which have been around for years. The only difference is that the local Internet Repeater or Gateway can be interconnected with repeaters and gateways hundreds or thousands of miles away. Instead of contact being limited to a few Amateurs within the footprint area of the local repeater/gateway, the footprint can be extended world-wide. If anyone thinks internet linking is “cheating”, then, by default, so is using a conventional RF repeater system, since both systems use 3rd party equipment to relay a signal from their station to a station which (usually) cannot be contacted direct. What is cheating - and lazy - is when a Radio Amateur uses EchoLink via computer, yet still thinks he is operating as a Radio Amateur! This is bone idleness, and the sooner repeater and gateway sysops block computer entry into their systems the better it will be for Amateur Radio. You will often hear these computer users complaining of the lack of RF activity in their area - excuse me!! Let these bone idle Amateurs bore the pants off other similar computer users on eQSO and CQ100 where, typically, conversation centres around weather reports and other inane subjects. Just go there and listen, and you'll know what I mean!
Since the time of Marconi, Radio Amateurs have striven to create wireless (radio) systems, but since the advent of the InterNerd some lazy Amateurs are now reverting to a wired system by sitting on their computers, complete with a £2 (3$US) microphone from Poundstretcher or WalMart, pretending to be a Radio Amateur. In this context, he/she is doing no more than what an unlicensed person can do on the InterNerd anyway! So nothing special there! And the lame excuse that “there isn’t a local EchoLink in my area” doesn’t hold water – you’re already half way there with your computer on EchoLink, so become a proper Amateur, just add a radio and make a system available to others in your area, instead of relying on others. You'll also have the versatility of being freed from your shack with the ability to roam with RF, which is what proper Amateurs do. UPDATE 24/5/09 Well, I heard it all today when monitoring my favourite EchoLink IRELAND Conference (2605) - an Australian computer user calling another computer user in UK (G4***) and asking "are you on frequency?" Also another well known user on IRELAND saying he can't be bothered with RF any more now he has Echolink (computer). Is this the way Amateur Radio will go out - with a whimper! UPDATE 26/7/09 Well, I heard even more today @ 14:25UT on EchoIreland: VA3** (normally a CQ100 adherent - need I say more) said "We (note that word "We" again) don't have any radio equipment here, and we ("we" again) don't want any anyway"!! How's that for a really dedicated Ham?!!* I despair. Now here's an idea - why don't those computer Hams that make us suffer their radio therapy requirements start up their own Therapy Room on CQ100, relieving us of the agony of enduring their slow, continuous drivel. If ever I get like that, I'll shoot myself! Meanwhile, if the cap fits, please don't call me. QUOTE OF THE DAY: "Let's face it - the average computer user has the brain of a spider monkey" - Bill Gates, Microsoft CEO. Perhaps that remark should also apply to lazy Radio Amateurs who use a computer direct (instead of RF input/output via Gateway or Repeater) for Radio Amateur conversation on EchoLink, eQSO and CQ100 !! So why not just become a pretend Amateur, use Skype and give up RF completely!!
D-STAR? Don’t make me laugh! The decline of amateur radio comes hand in hand with reduced use of VHF and UHF, evidenced by (i) the severe decline in SSB in those bands and (ii) most FM repeaters now grossly under-used. You just have to monitor simplex and your local repeater to know this is true. Then along comes D-STAR and all the geeky wannabe black box operators immediately start falling over themselves to buy expensive D-STAR equipment to speak to even less operators. If FM operators with inexpensive FM kit bought at rallies and flea markets don’t talk on regular FM, then why should they go out and buy expensive “new” digital technology to essentially do what they are not doing already? Just what they expect this “new” digital technology will offer them in terms of increased radio pleasure beats me! FINAL QUESTION So, how many REAL RF Radio Amateurs do you think will be left by 2018 - the next sunspot minimum? If we are not diligent in coaxing Radio Amateurs away from their computer connections, possibly very few!! Because there will be no point in taking the Amateur Licence!! Mind you, when using CQ100 you do get to have a pretty, pretend, HF set on your computer screen, which kinda makes you think you are a proper Radio Amateur, and that's after you've forked out 30USD p.a. for the privilege. That's my Rant over. I did warn you. Hope you enjoyed the Site, and I hope to meet with you on air (again) soon for a proper Amateur RF contact.
Other Local Attractions: Beer Quarry Caves Donkey Sanctuary Last modified: Sun Nov 15 20:05:06 2009 Does this page contain inappropriate content? If so, Report this page... |
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Quad Band Nested Dipoles for 3.5, 7, 14, and 28MHz Bands, splayed out like a fan in the same plane (i.e. running under each other). You can also run the legs out like a Maypole, but that would obviously take up more space.
