31 August 2007
Antenna
What we finally decided to do was a coil-loaded dipole. It had to be lightweight, short when transported, and easy to put together, and work on basically one band. If you're not dealing with multiple bands, that makes it much easier.
Wire antennas are out because we don't have a place to string them at the hotel where we're headed. Besides, we wanted to do our operating at on near the beach and not in the room. Otherwise, we'd just have asked the hotel to let us string a wire antenna.
So, what we came up with was a tuned dipole, made from aluminum arrows, PVC piping, some screws, washers, arrow inserts, an SO-239 connector and some wire for coils.
I spent the last few days reworking some cheap aluminum arrows into ordinary tubes, cutting off the nock end, removing the plastic insert that you screw the arrow head into and cutting them to the proper lengths based on calculations I did.
Last night I assembled the whole set up after finishing some short pieces of tubing for tuning, and placed the antenna assembly up on a short, 5 foot pole, on top of the trippod we'll be using, connected a 30 foot piece of coax, and fired up the rig as it will be carried, including the microphone and power supply.
It took me rougly 2.5 hours to get the antenna arms the right length and I kept showing high SWR of 1:3 or so and I couldn't seem to get it down. Finally I took the end tubing off from the coils outward, and placed a 30 inch piece in place. The SWR dropped down to 1.25:1, so I replaced that tube with a set of extension antennas from some old handheld CB radios and started slowly increasing and decreasing the length of the arms by first 1/4" then by 1/8".
After another flurry of jumping down off the deck, moving antenna robs, jumping back up on the deck, and setting the meters, checking SWR (I repeated this process at least ten times) I was down to 1.2:1 and I stopped there. I chopped a bit off of a couple of arrow-rods, and replaced the whole thing, then responded to a fella in PA calling CQ. He gave me a 5 and 4, then a 5 and 9 report. I was happy.
Here I was pushing 35 watts, on a home brew dipole practically sitting on the ground and I was getting a 5 and 4 report. Then I turned the antenna slightly and both his signal and mine went up.
A bit later, I called CQ and was answered by a Ham in New Jersey. I'm sorry I didn't write down the first call, but the second one was WW2QQ and he gave me a 5-4 then a 5-7. I think I can call that a successful antenna. The real test will come sitting on a beach in Jamaica, with a cold beer next to me, on the beach.
I'm happy. Except for one thing. The antenna isn't as "sturdy" as I'd like. I had to reinforce the center piece (PVC T-section) and the arms on either side with a fiberglass rod extending on both sides.
I'm concerned that the thread-stock I used is too small, but 8-32 screws are prettu much what fits into then end of arrow, so, I am stuck with that. They will probably hold, and I might be able to make the threaded portion a little longer to give it a bit more support, but the inserts aren't very long to begin with. I'll work something out, even if it is a string-eyelet type set up to give a little suspension to the arms of the antenna.
This weekend I'll set up the rig and operate from the back yard for a few hours each day and see what this antenna will do... or maybe we will climb Pikes Peak and set up there for a few hours!
73,
Rick Donaldson, NØNJY
30 August 2007
Frequencies
Frequencies:
Split frequency operation during operations hours on 14.19Ø+/- 1Ø KHz, TX, Listening 14.2ØØ – 14.23Ø (+/- 1Ø KHz)
Operation will consist of calling CQ DX on our calling frequency and announcing our call, QTH and “Listening between 14.2Ø and 14.24 KHz” (or whatever is called for if the chosen frequency is busy).
Radio will be preprogrammed with some VFO frequencies to listen on when we shift the VFO up and down.
Headsets will be used by both operators during QSO recording and conversations, so that extraneous noise will not interrupt us, nor will our radio traffic bother other resort patrons nearby.
One operator will record data, other operator will do contacts. We can switch off as necessary to give voice breaks and bathroom breaks… and someone has to get the drinks occasionally. (One must take all things into account in a tropical resort!)
A listing of local frequencies is on the next two pages, for emergency operations, International Groups, Caribbean groups and local HF groups in Jamaica. Both High Frequency as well as VHF/UHF frequencies are listed.
Our handie-talkies will be programmed with local repeaters for local repeater operations.
(Suggestions, comments welcomed)
29 August 2007
Location, location, location
From the Hunted aspect, that is the DXer that goes to some distant location to send his signals, the location has to be within reach, and the person or persons setting out on the trip have to make sure that everything falls into place.
JoAnne and I are finding this out daily. In our case, we chose the location prior to deciding to do DX. So, we've got a couple of good advantages. Our trip is paid for, whether we can operate our radios or not. No sponsors (if anyone wants to, certainly contact us with information!) and little else to worry about except getting there, and of course, getting weight down, building an antenna that is both transportable and will work, replacing a power supply... et cetera...
So, let me tell you a wee bit about the resort where we plan on spending our vacation.
It is a little 80-100 room hotel on the northern coast of Jamaica in Runaway Bay, St. Anne called "Club Ambience". This place is not a five star hotel, nor should anyone planning on heading there expect it to have room service or some other amenities you might find in the more expensive places.
What you WILL find for your cost is an all-inclusive price for food, drink, soda, water, room and entertainment. There is a night club, three bars, a swimming pool, and some awesome staff members at Club Ambience. The staff, without exception are helpful, great people. They have an entertainment staff as well, whose sole job it is to keep you busy and involved in things.
There are talent shows where the staff and guests get involved, doing everything from comedy to singing, to Shakespeare. There are sports, volley ball, Cricket and some staff-guest competitions (including beer chugging!) and some interesting things that I'd have never thought to do to entertain myself!
This resort is considered about a three-star place, and it has a separate house attached, with it's own pool that can be rented privately. There is outside dining at least once or twice during the week -- with lobster and other interesting meals, this of course, costs a bit more.
Your drinks, alcohol, or otherwise, are part of the cost, so tipping is appreciated by the staff but it's not "required". If you have Google Earth (download it for free) you can zoom in on the hotel yourself at 18˚ 27’ 47” N Lat. 77˚ 27’ 35” W Long. The image has changed slightly since the picture was taken. There is another walkway cover from the main bar to the eastern building (one part of the hotel).
If you look carefully at the northern most portion of the place, you will see a long walk out to the ocean, with a round building, that's a night-time bar area, and where we will be setting up our radio operations. We've already obtained some permissions to operate there, and we shouldn't have any trouble during the day.
My main reason for writing today is to tout the location. I think they are an affordable vacation, and in a good location. It's quiet, no children, adults only, not "wild" like some places we've heard about, and the staff and hotel are pretty awesome.
Here's their contact information:
Address:
P.O. Box 2Ø
Main Road
St. Ann, Runaway Bay
Jamaica W.I.
Telephone:
876-973-6167/46Ø5/
46Ø6/47Ø6
Toll free USA:
(8ØØ) 822-3274
Fax:
876-973-567Ø
E-mail:
info@clubambiancejamaica.com
Operated by:
Jemara Resorts Inc.
28 August 2007
Morse Code Watch
http://www.slashgear.com/tokyoflash-morse-code-watch-annoying-as-hell-246946.php
Another link to another complainer
27 August 2007
Icom IC-735
The Icom IC-735 is pictured on the left. This is the rig we'll be using (rather it is an image of a similar rig).
The radio tunes from 500 KHz to 30 MHz, and has a transmit output of up to 100 watts on the Amateur Bands.
When I obtained the rig, I got it from another friend of mine, Phil, AI4DQ and Harry, VE7JH. Along with the rig came a tuner, power supply and a semi-matching speaker. I'll be taking only the rig and an Alinco power supply (profiled here) to reduce the weight. Since I got the rig a couple of years ago, I have made a lot of contacts on various antennas around the house. Currently I use a tri-bander beam, and a multi-band vertical antenna, as well as a couple of wire dipoles. Each antenna seems to have it's own set of conditions under which optimum performance occurs. The real problem is that my dipoles aren't well aimed due to the yard arrangement. Instead of a good East-West radiation pattern, it's more SW-NE which somewhat limits by best signals from areas to which I generally communicate.
The rig has traveled across country with us, going from Colorado, to Kentucky, Michigan, the Grand Canyon in Arizona, and to the Renaissance-Festival in Phoenix one time a couple of years back. It has traveled up into the mountains with me at least once on a weekend camping trip where I was at 11,000 feet and made a few contacts from up there. Normally on the Jeep I use "Hamsticks", a series of vertical antennas for various bands. I have one for each band. They are decent, but I'm sure there are better antennas than those.
No matter which antenna I use however, the rig performs outstandingly. It's rather old, but it was well taken care of before I owned it, and I try to keep it clean, and free of dust. With a little luck, anyone who is interested in connecting up with us will be talk to that rig on the other end.
Jamaica Licensing Information
So, if you're planning a trip there in the next year, this information should be valid at least until next year. Also, Gerald Burton, 6Y5AG, of the Jamaican Amateur Radio Association advises me he believed that my license should be good for one year only from the date it is created. However, just as I was writing this, I received a note from Nadine at SMA who stated that the US $20.00 fee is for licensing that is good for THREE MONTHS ONLY. So, folks need to take that into account as well!
Jamaica
Spoke to
JoAnne’s Technician license should be in the mail, and we should see it within a few days. According to the lady I spoke to at the SMA, it should take less than two weeks for processing, and delivery of my Jamaican permit. We will apply for her Jamaican permit as well, but not until she has a new, valid copy of her license. Her old license still shows her as a “Novice class”.
The following is the cover letter being sent, along with copies of NØNJY’s passport, US Amateur license and a verified bank check for $2Ø.ØØ US currency.
Required Information With License Application:
- USD $2Ø certified bank check payable only to: Spectrum Management Authority
- Copy of your home license
- Copy of your passport (just the photo page showing passport number etc.)
- Form C
- Cover letter
The proper Address for Jamaican Spectrum Management Authority (Essentially this is the “FCC” of
Spectrum Management Authority
2nd
53
Phone: (876) 929 - 855Ø / 852Ø
I'm not sure of the number of Hams in Jamaica, but it appears there are at least 100 or so. Some have responded to help requests from me, some have not, but all that have were helpful, kind and supportive. The people in the SMA were all pleasant -- and they reminded me of what Government workers OUGHT to be like, rather than some of the cynical, upset, and sometimes just rude people we run into in the US from time to time.
Site Notes
Power Supply
I had several suggestions from several sources including Bob, K0NR. All of them were reasonable, but I settled on the one below. Wes (K0HBZ) responded with a type of supply. He sent me back an email with the following notes:
"There's only ONE power supply to have -- Alinco DM-330MV -- $149. They're incredible, I have two (actually three but a lightning strike damaged one of them) and have been using them for several years. I run my backup HF station (Yaesu FT-847) and all other 12vdc radios and equipment in my shack off it. 30A continuous, 33A peak."
Armed with that information I started searching for the power supply on the internet, found one at Ham Radio Outlet for $129.00. I ordered it and it arrived the very next evening, and I tested it on my rig that evening, made several contacts, received good reports and deemed it more than adequate.
The output on the back consists of two heavy duty terminal connections with knurled banana-plug type connectors. I built a cable and connector for the IC-735 to the power supply. This particular system can supply 32 amps, is a switching supply so is significantly lighter than a supply with a transformer. There are, as you can see, other outputs on the front for other devices.
One of our main concerns is taking communications equipment into Jamaica. I've been assured by Jamaica's Spectrum Management Authority, and some local Jamaican Amateurs we should have no problems. Obviously our licenses will accompany us, as well as copies in the equipment.
The second major concern is carrying the gear with us. We have pretty much decided on hard-sided luggage with wheels, so that we can still take one bag each, plus our carry on backpacks. I've read all sorts of things about putting equipment into luggage, and then worrying about it. However, I made several hundred trips from Washington, DC when I worked for the White House Communications Agency, carrying (not counting my OWN bag) on Vice Presidential trips, up to 25 separate cases, boxes, suitcases and other transports, at one trip. I never ONCE lost a piece of luggage or equipment. It always seemed to arrive, occasionally late, but it got there. So, I'm going to "trust" the airlines to do a good job and get our stuff there.
Unlike many other folks who ship equipment in early, we don't have that luxury, nor ability and it would most likely cost us even more money than just carrying it in. Between our two bags, we ought to be able to shift our weight around enough so that neither bag is overly heavy and the equipment will be divided up between us. This should reduce the weight for both of us, allow us to carry enough clothing and our normal trip stuff with us and let us still get our equipment there, and back home again.
The other thing is JoAnne has to drag her own bag through the airport once we collect things from Customs and I don't want her struggling with extra weight. I don't mind being a little heavier on the Bag-Side, but, don't really want to take 75 pounds in one bag. No clothes then!
Sometime soon, I'll weigh the whole shebang (once the antenna is completed) and see what the total weight, plus coax will be, then work out the clothing requirements last.
As of last Friday, we hadn't really picked an antenna yet, but have looked at several things, including a purchase of a W3FF Buddipole -- at a cost of almost $400.00. While it appears to be a very cool antenna system, extremely portable and used by several DXpeditions, we decided that was a bit out of our price range. Besides, having been a communications guy for a long, long time, and setting up almost anything in a pinch as an antenna, mostly wires, zip cord and military equipment, it was decided we build one and use as much stuff from home as possible and keep the price down. This of course, didn't preclude us from purchasing a few items at a hardware store this past weekend.
After a bit of brain storming over a couple of beers at our favorite food place, and quite a bit of drawing on napkins, we came up with a design, some calculations and then tried to come up with some kind of simple hardware we could make into an effective antenna.
We decided the following:
1) Multiband homebrew dipole.
2) It had to be light, shortened and we needed to be able to stand it in a free-standing mode with a tripod or some sort.
3) Wire dipoles were out because of the previous site surveys showing little or no antenna supports available (trees!) and we wanted something sturdy enough to stand on its own with little sag.
4) The antenna had to be fairly easy to assemble.
5) It had to be reusable, and it has to actually LOOK good as well.
We tried some extendable/expendable curtain rods and some fiberglass tent poles that are held together with an elastic string through the middle. Both sagged considerably, and were weaker than we expected. The curtain rod idea was good, but we weren’t going to use the rods as radiating elements, and couldn’t come up with a good way to put coils in place. We tried inserting wooden doweling into the curtain rods, then started thinking about the interaction of the metal with the actual antenna. That wasn't going to work well.
The fiberglass poles were just a bit heavier than we wanted, and again, with not a good way to mount things. They sagged as well, more than I thought was usable. Putting a coil and some wire along the fiberglass shafts would have worked fine, and simple electrical tape to hold it would have worked well, but the antenna would have been 16 or 18 feet long, even with the loading coils and it would have sagged miserably.
Then the idea struck us to use aluminum arrows. JoAnne had already mentioned arrows once, but as is typical for me, I was thinking one thing and she was thinking something else. I was looking at SUPPORT (and thinking wooden) and she was actually thinking of the technical aspects of using ARROWS (and thinking METAL -- Duh on me!).
So, on Sunday (yesterday), we purchased a handful of $3/ea shafts, removed the plastic arrow head inserts, and cut off the fletching and nock end of the shaft. This left us with a set of hollow aluminum tubes. Next we inserted metal inserts.
At this point, I only finished a few of the shafts yesterday afternoon, and we went off to a birthday party for one of our grandchildren. (Side note: We gave her some walkie-talkies, with a Morse code button.... so we're starting her EARLY, she's four and already knows her alphabet, so we figure by next year she will be getting her Technician license!)
Today, using a program found at K7MEM’s site, I calculated a slightly shortened, loaded dipole antenna. http://www.k7mem.150m.com/Electronic_Notebook/antennas/shortant.html
The actual “design” of the antenna will be similar to the W3FF Buddipole, including a tripod to hold the antenna up.
The center feed will consist of a T-section of PVC pipe, an SO-235 connector, loading coils for 20 meters and coils made from PVC pipe, end caps and associated hardware, screws and threaded arrow shafts. As of 27 August, the antenna is partially built and we expect to do some hard testing on 1 September 2007 to see how the antenna works.
My thinking is that we will use PVC piping as the mast section, cut into shorter pieces for transport in our suitcases on the trip. We'll use some PVC couplings to connect the pieces into a longer piece. The tripod we're going to use isn't the most sturdy thing in the world, but it was an old camera tripod and should hold this antenna up with no problem.
To build the coils I will be using short pieces of PVC pipe with end caps on each side, drill holes for the wire, and run the wires to hardware inside the pipe, allowing me to screw the newly made "Arrow Elements" to either end (on the end caps) of the coil for center loading on the antenna. I'll install an SO-239 connector on the T-section, to allow easy connection of the coaxial cable and probably install, if necessary some kind of ferrite beads at the connector to prevent RF from radiating from the coax.
Having tested some of the arrows by screwing them together already, I found that this is a very STURDY antenna element and shouldn't sag very much at all. Calculations are as follows:
Total length of dipole: 16 Feet long
Element Length Before coil: 4 feet each side
Secondary Element (Coil Plus element): 4 Feet each side
Coil specs:
Inductance: 8.76 uH
Diameter: 3 - 1/4"
Length: 1 - 5/8"
Turns: 10
Wire: #12
More to follow on this antenna. When I get it assembled, I'll try to post some pictures of it all set up so you can see what it looks like. We should be able to tune the antenna more carefully once it is put together, by adding or subtracting some length off the ends of the elements.
I think I'm going to call it a "DX-Stalker" because the arrows I'm using are made by Easton, and are called "Stalker" arrows. They are camouflaged. Perhaps we'll call it "DX-Prey" since, we'll be the DX station!