Oh boy! Now it begins!
Just 2 weeks until the big ARRL Field Day! I've had my Icom IC-735 connected to a doublet antenna at home for a couple of weeks now and I've been getting the feel of how it operates. I've decided that for Field Day 2013 I'll use a ladder line fed doublet in an inverted vee configuration since the site we'll be operating at doesn't have as much room as I originally had wished. The good news is that it is a lot easier to set up and tear down, and would be something I could take to the park nearby and setup in a true emergency.
I also acquired an additional Duracell Powerpack 600, this will be connected in parallel with my first Duracell Powerpack 600 that will be charging via a 50 watt solar panel (and awesome solar charge controller). Hopefully this provides enough storage (56 Ah) to make it through the night. My radio draws about 1 amp when receiving and about 2 amps when transmitting QRP, 18 amps at a full 100 watts.
My strategy for Field Day 2013 will be to operate QRP in a "search-and-pounce" style: looking for stations calling CQ and replying. If things completely die off, I'll do my best to call CQ, but running QRP will make that difficult.
My backup plan is to increase power, but unfortunately this will also take us out of the "1B Battery" category and we would also lose the huge 5x power multiplier. We would move into the "1B" category and we could still claim the 100 point "alternative power" bonus points, but it will be worth trying to stay under 5 watts since that 5x multiplier could make up the difference in points.
On a side note, while I love all the views my site is getting, I really need to know that you are enjoying the content! Please feel free to send me a fiver (or whatever you could afford), or even just email me a note. I would love to hear from you!
As with anything else, trouble begins as soon as someone says "Check this out!"
I was fortunate to be able to pick up my Icom IC-735 a couple of weeks ago after being completely worked over, new variable capacitors, new battery, new CW narrow filter, fixed antenna connector, and opened for 60 meters.
Bud Garside (W7ARS) at Amateur Radio Service (firstname.lastname@example.org, (503) 554-8831 and (503) 538-1638) asked me what type of antenna I was going to be connecting it to and I mentioned I was gonna start working on a fan dipole (three-band) antenna
as soon as I was back in town after a couple of business trips to San Francisco.
His next question was if I had an antenna tuner and I let him know of my awesome score
at the Salem Hamfair (the MFJ-948) and he said that before I build the fan dipole to just get some ladder line and make a single dipole for the lowest frequency I was interested in. He said the tuner would do the rest!
Of course I really had no idea what he was talking about as I previously used a G5RV antenna on a Yaesu FT-897D without any luck at all and quickly dismissed any antenna fed by ladder line. That all changed though when I hooked up my IC-735 to my home-built dipole antenna
on 17 meters to see if I could pick up any local stations here in Portland, and ended up listening to stations in Tokyo and New England! Sure, I was using coax to a resonant dipole but I'm beginning to think that the FT-897D I was using previously just wasn't up to the task...
Now that I'm back in town and not traveling again for a while, I'm researching articles written by Steve Ford, WB8IMY, and learning a lot about ladder line fed antennas and I'm thinking I will have to give this a try before I build the fan dipole antenna. If it doesn't work, I can always call it "experimentation," but the evidence leads me to believe this might be an excellent option for my space limitations!
| The Lure of the Ladder Line - Steve Ford, WB8IMY|
|File Size: ||1004 kb|
|File Type: || pdf|
| The SWR Obsession - Steve Ford, WB8IMY|
|File Size: ||1205 kb|
|File Type: || pdf|
| The Classic Multiband Dipole Antenna - Steve Ford, WB8IMY|
|File Size: ||1162 kb|
|File Type: || pdf|
Like most things, I had no idea what I was doing until there was a problem. The problem was that I was murdering my batteries!
Here I was with my 8 Ah SLA battery wondering why I couldn't get more than a minute or two of use before it was dead. I thought I was doing everything right by leaving the charger connected until I was ready to use the battery, but little did I know that by using a basic unregulated charger I was committing battery homicide.
The problem is that a basic charger for these SLA batteries that you can pick up from any hobby shop is nothing more than a 13.8 volt, unregulated wall-wart power supply with a couple of alligator clips. What most people don't realize is that as the resistance increases (as the battery charges), the voltage on the unregulated power supply increases.
This is where I introduce you to the best battery technical resource on the internet: PowerStream Technical Resources for Design Engineers
Here you will find an article on how to charge a sealed lead acid battery and in that article you'll find a voltage chart that includes the "gassing voltage." At about 20 degrees C, you'll notice that the gassing voltage (that is, the voltage that the electrolyte becomes a gas) is 14.49 volts for the typical 12 volt SLA battery.
When measuring the voltage on my unregulated wall-wart power supply hooked up to the battery, I found that it was above 15.5 volts!
So the good news is that I knew why my battery was bad, the bad news is that since it is a sealed lead acid battery I couldn't just stick more electrolyte in an hope the damage wasn't permanent (I did end up opening the top forcefully just to try, but the battery was too far gone for it to do any good).
As I noted in a previous post
, I currently use a Duracell Powerpack 600 as my "emergency" power supply so the question becomes how do I not torch this battery too? Well, checking the PowerStream website again, you'll see that there is a "standby use charging" chart, indicating that a voltage between 13.56 and 13.86 is best. Also in that same previous post, I talk a lot about solar power and how I use a CirKits SCC3 as my controller. The best part is that the solar panel can be swapped out with a DC power supply (regulated is preferred, but an unregulated one will work if the voltage stays low enough). So, at home I just plug the controller into the Powerpack and then plug in a basic DC power supply (actually the one that came with the Powerpack) into the controller to regulate the charge.
The same voltage rules do apply with all batteries and PowerStream has done a great job at documenting all of them. Definitely check it out and stop murdering your cells!
Just a quick post them evening with a couple of my recommendations of other amateur (and other related) radio websites I like to visit on a regular basis.
What if a world existed where we could use our amateur radio license to have our own frequency spectrum to do wifi? Well, wonder no more as a segment has existed for many years in amateur radio to promote a technology called high-speed multimedia radio
A lot of HSMM development has been with the Linksys WRT54GL router since it can run custom firmware. A large project called HSMM-MESH
has custom firmware for this router that automatically customizes it for amateur radio use. Their firmware will make your router a member of a "mesh node," allowing connections from fellow routers running the same firmware without any additional configuration.The downside to the HSMM-MESH project is that it currently configures the Linksys router to use the standard wifi channel 1 (
2.412 GHz) where there is a lot of local, Part 15 interference. The solution is to move to a different frequency that amateur radio license holders can use.Ubiquiti Networks creates wifi equipment for the commercial and WISP industry and they just so happen to create hardware for the 3 GHz band (3.400 GHz to 3.700 GHz), right in our 3.300 GHz to
3.500 GHz allocation! The downside here is that the HSMM-MESH project hasn't yet created firmware for the Ubiquiti Networks products, but for such short-range (a few miles) communications it shouldn't be too difficult to coordinate a network configuration.Ultimately, the best solution would be to make or buy some type of transverter for the Linksys WRT54GL that would move it up into the 3 GHz allocation (the Ubiquiti products use an internal transverter to get into 3 GHz).
Amazon.com: http://amzn.com/087259839XARRL Store: http://www.arrl.org/shop/ARRL-s-Small-Antennas-for-Small-Spaces/While looking at the "small" collection of amateur radio books at my local, small-town bookseller, I came across the ARRL's Small Antennas for Small Spaces: Projects and Advice for Limited-Space Stations.While I'm fortunate to live on a pretty decent (7,000 sqft) city lot without a homeowners association or any CC&Rs (
covenants, conditions and restrictions), I have to take into consideration what my budget supports and what will have the highest W.A.F. (wife acceptance factor). Unfortunately this means I don't get to have a 50 foot tower with a mess of antennas and dipoles coming off of it, however I have a few trees and the wife doesn't mind wire strung around for a few days at a time.What I really like about this book is that it shows you what could be done with the space inside of the home, without even stringing a wire outside. The book starts off with quite a bit of antenna theory and things like the type of coax to use and what exactly an antenna tuner accomplishes (and what it doesn't). The book also talks a lot about portable antennas and commercial limited-space antennas, because we don't have time to make absolutely everything from scratch!The first third deals primarily with HF antennas, the second third with VHF+ antennas, and the last third is filled with various antenna projects taken from the pages of QST to get you started with experimentation
. It's a great book, especially the beginner looking for some ideas as a launching point.The label price is $25.95, however online it can be found typically for $22.95 new.
Apparently someone was reading my mind last week when I was thinking that I should plan on testing out my Field Day 2013 setup as this email came through on the ARRL Oregon Section mailing list
From: "Dick Frey" <email@example.com>
Sent: Thursday, February 21, 2013 10:16 PM
Subject: 7QP is May 4th this year
This is your annual 7QP early warning message. Warning? Well, you don't want it to creep up and find you unprepared, right?
Now is the time to:
• Go to the kitchen and put May 4 on your wife's calendar to preclude any schedule conflicts.
• Start working on that new ______ antenna. (fill in the blank)
• Think about getting a group together to activate a rare county (list below).
• Put a program together to promote 7QP at the next local club meeting. They are always looking for new programs, right?
• Download the free N1MM logging program and practice using it in a weekend contest.
• Gather a group of new hams and plan a multi-op to teach them about HF operating.
Until then, the 7QP staff will be working hard to organize activity from all the darker corners of 7-land. To this end, if you plan to activate a particular location, send your intentions to firstname.lastname@example.org. If you would like advice on what the needs are, please drop us a line. We want to make sure that all the Oregon counties are active this year... and beat those guys down in Arizona for the maximum participation award.
Information about 7QP is available at http://7qp.org web site: maps, county operation information, rules, log sheets, FREE programs to use for computer logging, special techniques - lots of neat stuff.
Again, thanks for your support of Oregon's share in the best QSO party in the land, the 7th Area QSO Party. See you again in about 6 weeks with another reminder and updates.
Dick Frey, k4xu
7QP Oregon Captain.
There are less than 2 hams active on HF in the following Oregon counties: Wallowa, Malheur, Lake, Harney, Grant, Wheeler, Sherman, Gillliam, Jefferson. Wasco, Baker, Union and Linn are are in the "rare" category with less than 10.
Needless to say, I think that the first Saturday in May will be an excellent opportunity for me to get things set up to try out and will get me motivated to get everything together sooner than later!
When amateurs start planning for Field Day, one of the major considerations they make will deal with how to provide power for operations. The American Radio Relay League (the Field Day organizers) have a variety of rules to discourage using standard commercial power, so most look toward various gasoline or diesel generators to keep their operations going (the Honda EU2000i is a fan favorite) when alternative, natural power sources, would work just as well without the negative effects to the environment. The ARRL will even give bonus points to those stations making at least five contacts on a natural power source like solar, and extra point multipliers to those stations operating QRP (under 5 watts) while exclusively operating on a power source other than commercial mains or motor-driven generator (a.k.a. a natural power source.For my Field Day operations this year, we will start with about 150 watts of solar panels, probably three 50 watt Instapark panels I got off of Amazon.com. These aren't the cheapest solution, however their size makes it very easy to transport them in a hatchback or sedan and wiring is a snap by using standard Anderson PowerPole connectors.My solar panels will be connected in parallel to a CirKits SCC3
solar charge controller kit I built. What's really nice about this controller is that it is a constant-voltage controller, allowing me to use a variety of battery storage chemistries by adjusting the maximum charging voltage.This year, my battery storage will primarily be a Duracell Powerpack 600. This system utilizes a 28 amp-hour sealed lead-acid battery
and should keep my transceiver running while the sun isn't shining. I have two other 18 amp-hour sealed lead-acid batteries that I'll be bringing as a backup in case we have less than optimal sun conditions or charge controller issues.You might be asking what we'll do about everything else that needs power, like lights and computers and such? Well, the rules for Field Day specifically state that if equipment (like computers) are not connected to the radio equipment, they are exempt from the necessity of being connected to emergency power (like a generator or a natural power source). So, we'll be running a couple of extension cords to our Field Day tent just for those items. If I happen to be able to get another Duracell Powerpack 600, I'll be running my laptop logging computer off of the solar charging system as well
.I'll be going through my power system setup as we get closer to Field Day and I'll even go into using LiFePO4 batteries
(and hopefully demystify the secrets about being safe with them)!
For Field Day 2013, I anticipated that I would be using a site that wouldn't be the best for just throwing an antenna into a tree and boy I was right. This year, my site is very flat and, other than a few bushes, is barren.
The rule for getting antennas in the air is always "the higher, the better." To keep things fairly simple, I decided that 40 feet high would work as long as it was a horizontal dipole, about 60 feet high for an inverted vee dipole.
Searching around on eBay, I came across W2SRQ
's store where he sells all kinds of surplus military aluminum mast. Originally this stuff was used to hold up camouflage netting in the desert, but now gets a second life as a quick, lightweight, antenna mast for amateur radio. I decided to buy his 30 pole kit. This includes enough parts to build three masts, about 37 feet in height each, including 6 guy rings and bag.Next, I needed a way to get the pole to stay on the Earth wherever I place it. I came across Barnes Military Surplus and Radio on eBay (also operates GoVerticalUSA.com) where I purchased three antenna swivel stakes, a bag of tent stakes, and a couple of extra bags for the masts (one bag per each of the three masts). I also picked up antenna guy rope from The WireMan when I ordered my dipole wire and some
carabiner clips off of eBay.I will be building a PVC topper for each of the masts to get them up to 40 feet and add a pulley for easy access to the dipole for installation, tuning, etc. Details will follow in a future post!
While I commented a few posts ago
that I was excited to get started working on Field Day (and getting a site confirmed), I've been working on Field Day related items for a few months now, specifically the antenna and mast. Today I'll go over what I currently have planned for the antenna.
The primary activity for Field Day is going to be on 20 and 40 Meters, however other bands shouldn't be discounted as amateurs will be wherever the action is (and band openings)!
The portable dipole antenna I posted about yesterday
will be used as my high-band antenna, covering the 10 Meter and 15 Meter bands during the contest (12 and 17 Meters don't count for the contest and my Icom IC-735 doesn't go up to 6 Meters). I will be building a separate fan dipole antenna for 20, 40, 80, and 160 Meters.
The first thing you'll want is a good balun
, you don't need a balun and could directly feed the fan dipole with coax or balanced ladder line, but there are risks of radiating from the coax cable (or balanced ladder line). Sometimes, this can be a desirable effect (like with a G5RV antenna
), however other times you could end up with RF at your transmitter, not a good thing! I decided to go with a professionally built balun from Balun Designs
as these are heavy-duty and built to last!
The next item you'll need to make an antenna is the wire! To cover all four bands that I was designing this for, I estimated about 500 feet of wire. This should give me plenty of excess to tune the bands and give good separation between each leg (about 6 inches between wires). The antenna will be hanging from the 80 Meter legs (the 160 Meter legs will come off perpendicular to the 20/40/80 part as an inverted vee
since it's a total of 250 feet long), so I knew I needed something heavy-duty that could support the weight and be durable for temporary use whenever needed. I decided that the 13 AWG wire from The WireMan
(#531) would be the best option for the price.
I'll spare all the details on measuring and mounting the fan dipole antenna as I believe Hamuniverse.com has done a pretty good job on their Multi Band HF Fan Dipole Antenna Design
page. My next post will go over the antenna mast system that I'll be using for Field Day 2013, so stay tuned!