Friday, June 28, 2013

RM11699 is a Well-Intentioned Bad Idea

I have been an Emergency Communicator. I understand the limitations of what can and cannot be communicated via amateur radio during emergency activation. I also believe that Mr. Rolph AB1PH has the best intentions in his Petition for Rule Making to the FCC (RM11699). I still think it's a bad idea to grant amateurs permission to transmit encrypted messages in any form other than remotely controlling equipment.

There are many things happening in an emergency, many of which SHOULD be encrypted for the protection of those involved. However, messages of this magnitude, should ONLY be handled by professional Emergency Personnel with the ability to act on the encrypted information. Such messages are in NO WAY the responsibility of amateur communicators. 

Amateur Radio has proven itself over and over as a viable and robust emergency communication tool and it should continue to serve the public in times of need by opening communication, "when all else fails." But, the moment amateurs are asked to shoulder the weight of highly sensitive medical and tactical communication, it is no longer amateur communication. In asking the FCC to grant the right to transmit and receive such communications, amateurs would open themselves to the full ramifications of mishandling said communications, which they are not--nor should they be required to be--trained to handle. Amateur Radio is first and foremost a hobby. Albeit a hobby that can serve the public in times of need.


It is my hope that the ARRL and the FCC consider the weight that this petition asks them to bear and that it is ultimately denied. 

Friday, June 21, 2013

Quick and Dirty Field Day Doublet

Last night I got home with a few hours of daylight to spare (thank you very much Summer Solstice) so I decided to throw a quick and dirty doublet together for Field Day. Like most hams, I have a few (unless you ask my XYL, then it's hundreds) boxes of random "junk" laying around that I use from time to time to experiment, so I pulled out a few bits and pieces to put the antenna together. In case you've never built a doublet, here are my reasons for doing so and the theories that I employed.

There is a lot of confusion surrounding the terms "doublet" and "dipole," so let me wade into the murky waters and explain the difference as I see it. Technically, there is none. They are two names for the same thing. However, the difference, in common parlance, lies in how you feed said antenna and whether the antenna is cut to resonance for a target frequency. 

Typically, a "dipole" is a resonant antenna for a given frequency and is fed with coax. There are many purveyors of 40 meter, 20 meter, 10 meter, etc. dipoles that include a PL259 connection at the center connector to attach your coax. These dipoles are typically resonant near the center of the given bad and give adequate bad with to allow the ham to operate anywhere on the bad without the need for a tuner. Try to load them up on another band then their design frequency however, and noise, smoke, silence, and cursing often occur. 

"But I have a fancy built-in tuner in my rig, so I can load that 40-meter dipole up on 6 through 160, right?" 

Maybe, but the impedances of other bad on a resonant dipole can be amazingly high. So, in short, it's not a good idea to test fate. There are however tuners that will allow you to load up on other bands, but the signal losses of doing so offer drastically diminishing returns. In other words, you might be able to tune that 40-meter dipole up on 160-meters, but it might work as well as loading up a Soup Can. 

A Doublet (again, I'm speaking of "Doublet" as is generally understood. Both "dipole" and "doublet" mean the same thing), is a little different. The basics are the same. You generally cut a doublet antenna to be a half wave long on the lowest frequency you plan to operate. Impedances on other bands will still be amazingly high, but the losses will be much lower and turn our "Soup-Can" into a usable, although compromised, antenna. How? I'm glad you asked.

By using ladder line or open wire feed-line (two wires separated by spacers) the signal losses are dramatically reduced. The ladder line is then fed into a Balanced Line Tuner (or a 4:1 Balun) and then coax to your rig. A Balanced Line Tuner like the CG Antenna Ltd. Remote Auto Tuner is placed where your ladder line meets the ground and powered by a battery (in my case an SLA battery which is charge by a 5W Solar Panel (Pics coming soon) or by a "Bias Tee Power Injector" such as the MFJ-4116. When the auto tuner senses RF energy it quickly measures the SWR and makes the necessary adjustments to put it back in a usable range. Remote auto tuners like the CG can seamlessly deal with the wild impedance differences between bands and allow you to operate on 6 -meters one minute and 40-meters the next. So now you can pick a Saturday and knock out that DXCC you were thinking about getting someday. Maybe, but there are a few other things to consider.

Our 40-meter Doublet and subsequent Balanced Line Auto Tuner are doing their job singingly, but it is important to realize exactly what they are doing. Like a 40-meter resonant dipole, our antenna will project the bulk of it's RF energy 90° to the antenna in both directions, in other words, off the sides of the antenna. This is assuming that the antenna is flat-top and at least 1/4 wave (33 feet or so) above the ground. When we move dow to 20-meters, our antenna will still put the bulk of it's energy out at 90°, but as we go higher in frequency (17-meter, 15-Meter, 12-Meter, etc.) our two predictable lobes will start to break up and lose energy. by 15-meters, there will essentially be 4 lobes at 45° each. I wish I had the ability to plot this out for you, but at the moment I don't. Suffice it to say, that you must consider the trade-offs when ever you deploy a multi-band antenna. 

Wow, that was  a lot of theory to get to my application. So, I decided to deploy a lightweight 66' (half wave on 40-meter) doublet fed with 300Ω Ladder Line. I built this antenna to use for Field Day 2013, but it will also be used regularly when operating portable with my Hendricks PFR-3. That being the case, I wanted it to be pretty bullet-proof without adding too much weight. Also, I wanted to save the nice 500' spool of antenna wire I have to complete an 80-meter full-wave loop this summer. Luckily, my fellow Ham and father recently unloaded a spool of hefty speaker wire on me.


I found this Wireman 814C in a box and drilled the holes a little wider to accommodate the wire. I soldered everything up, added some shrink-wrap (in case it stays up longer than planed) and put it away for the weekend. 











As you might notice, I need to buy a heat gun as my lighter really charred the shrink wrap, but at least it's still functional. I'll report back on how the antenna performs, but in the meantime, I hope I've given you some food-for-thought on dipoles vs. doublets.



Thursday, June 13, 2013

New Mobile Shack: Nothing Goes as Planned, Right?

With all intentions of following my plan for an install on my new car, I dove in between rain storms over the past two nights to get everything mounted and ready for years of mobile VHF/UHF enjoyment. About ten minutes into the project, it became apparent that things were not going to go exactly as planned.

The antenna mount I chose (see THIS post for details and links on the gear I used) mounted up in a heart beat. I only moved it once so that the antenna (when the trunk is opened) would not slam the roof of the car, potentially causing damage to one or both. I took a piece of ground strap I had lying around the garage and slipped it under the mount to bond the antenna to the radio and the farm of the vehicle. In hind site, it was a pain to run all the ground strap, but it was also well worth the effort as everything is quiet and appears to function very well. It's always amazing how much a solid ground plane work in your favor.

With the antenna mounded, it was time to run the feed line and ground strap, which took several attempts. Every time I thought I had found the perfect balance between keeping cable out of the way and being able to close the trunk, I found I was mistaken. After half an hour or so, I got it right. Again, I'm glad that I took the time to do it right. 


Next, I mounted the radio body to the car under the back dash. Unfortunately, I stripped a few screws in the process, which meant re-drilling. Just when I buttoned it up I realized that I hadn't laid the ground strap under the bracket. So off it came again and then back together. By this time, it was nearing midnight, so I wrapped it up.

The next morning, I re-thought the idea of fabricating an in-cabin mounting bracket. I just didn't have the time to do it well. Luckily, my father (also a ham) has a barn full of random bits and pieces. I called over to say, "hi," and have him rummage through boxes. :) He found just what I needed and dropped the pieces off later that day.

I mounted everything up quickly and set off to run the power and signal through the cabin and firewall. Oh boy, that was fun. Luckily, I was able to follow the hood release cable through the firewall and with a hour or so of tugging and contorting myself into ungodly under-dash positions, I had power. 

With the install done, I powered up the laptop, loaded a few frequencies, and programmed the radio. I'm happy to report that it is quiet, effective, and seems to work well, in spite of the fact that I still haven't received the planned antenna. In the meantime, I had another dual-band NMO to attach to the mount for testing and such. 

This is the first time I really took the time to do a mobile install correctly and I'm very happy with the results. I think my wife was even impressed that there weren't tangle wires snaking in every direction like my previous installs. The whole thing looks good, is out of the way while easily within reach, and works well. Sometimes the plan has to go out the window to get things right I guess.

73





Tuesday, June 11, 2013

Field Day Approaches

Field Day is NEXT WEEKEND! Wow, that came fast. It feels like yesterday that I was bemoaning the fact that I had to work the entire weekend of FD2012. This year, I don't and I've been preparing my family for my absence long enough now that they roll their eyes when I continue to remind them. So I'm in full planning mode.

I was hoping to run QRP CW as a 1B station this year, but I've been slacking a little in the learning department and my CW is still way too shaky to commit to an entire weekend of CW only. I will still try to gather a few CW contacts with patient ops, probably in the wee hours of the morning when the pile-ups are few and far between and less people will be listening to my shaky fist. For the most part, I'll be operating SSB. 

I've thought long and hard about where to celebrate this year's festivities, but my equipment is weighing down (literally) my options. Because I will be working SSB, I only have a full size 100W rig available. While I have no problem losing the computer and paper logging (see THIS post), my transceiver alone will draw more power than I can easily carry. Since my house is 100% solar powered during the day, I may operate from the QTH and utilize a bank of AGM batteries I have stashed for just such an occasion. That feels a little boring though. Maybe I'll set up a tent and "camp out" for the weekend. I have 9 acres to spread out in and plenty of trees to test out some quick and dirty antenna deployment options. Who knows?

It's times like this where I really miss being a part of a club. I still have had zero luck getting in touch with anyone listed on the ARRL club list for Northern NJ. I'm hoping to wrap up my mobile install tonight, so I can start monitoring the local repeaters and maybe find a few other like-minded hams to steer me in the right direction, or to start a new club with. Until then, I need to get ready for next weekend. 


What are your plans for Field Day?

Friday, June 7, 2013

New Car New Mobile "Shack"

There are so many things to consider when buying a new car, but the whole time I was shopping for my new ride, I was envisioning my next mobile "shack." For the last 7 years, I have been driving a lifted Jeep Rubicon. It has been a great vehicle. I've put nearly 200k miles on it and never had a major issue. It was a radio-lover's dream. There were so many places to put gear, antennas, etc. that it now resembles an AWAC more than a passenger car. My new ride…not so much.

I ended up purchasing a 2013 Huyndai Elantra CoupeMy decision to buy a this particular car was a mix of priorities: fuel efficiency, warranty, and price. This car will run out of it's factory warranty just before my son gets his driver's license. When he does, it will still have a few years of warranty on the drivetrain, so… While those were major factors in the purchase, I would be lying if I didn't mention that it was the only small commuter type car I looked at that had a reasonable platform for mobile Ham communications.

I'm not sure how new your vehicle is, but flat surfaces to mount radios are scant on newer cars and trucks. Furthermore, flowing body lines and side curtain airbags make mounting antennas a challenge. So I began looking into ways to mount my radios, antennas, GPS, etc. that were wholly different from what I was used to. The Elantra has a largely flat dashboard. My GPS will live there, rather than semi-stuck to the windshield where it always decides to fall off during complex lane-changes at unfamiliar exits. My radio's go in the trunk.

This choice was different for me. While I've always had a VHF/UHF Dualbander with a removable faceplate, I've never needed to separate them. On this car, it just makes sense. By mounting the radio under the rear window, I will only need a few feet of feed line to the antenna (more on this in a moment) and I can ground the radio, mount, and antenna all together to the body and frame of the vehicle. I never had to worry about so much paint on my Jeep, so this will allow me to grind some away without alerting the XYL. 

I'll be performing the install in stages to avoid angry calls from creditors and allow me to perfect one or two bands at a time. This weekend, I'll be running power directly from the battery, fused on both positive and negative to the trunk. While I have all the panels pulled to do so, I will also run the seperation cable from my FT-7900 as well as a CAT5 cable for a future separation of either an FT-857 or Icom IC-7100. One last cable to make the run will be coax, to accommodate another external antenna for my BC-396XT, which goes just about everywhere with me. For this keeping track, I will not be running any cable for audio. Instead, I will be mounting an external speaker above the trunk in the passenger compartment, just like an old police cruiser. 

Once that is done, I get to the fun part. I'll be breaking out the Miller Passport and welding up a mount that will attach to the front passenger seat bolts. Yes, I know they are available commercially, but mine will be much cooler and manly; trust me. When finished, it will hold the face plate from my FT-7800 with room to mount a second (future) faceplate and give me a location to hang a mic and my BC-396XT. If I'l feeling extra saucy, I may also include an iPhone mount. 

The antenna mounting, will be a whole different game. For the moment, I will be using a Comet SBB-5 NMO 1/2 wave on a Diamond K400CNMO comet mount. Eventually, I will drill through the trunk lid, but I want to wait for a better idea of what HF antenna I'll need to mount before committing to something permanent. As I mentioned before, the mount will be bonded to the body and farm of the car, hopefully giving me a solid ground plane. 


So that's the plan. I'm curious to hear what other mobile installs Hams have done lately. I'm especially interested in how you have gone about grounding trunk lid antenna mounts. If you have anything to share, please do. Now, where did I put my welding helmet?

Tuesday, June 4, 2013

Not so Common Sense Tips and Tricks for Public Service

If you follow me on Twitter (@rocknrollriter), you may have noticed that I got a little bit bent yesterday morning by a thread on eham.com. If you don't follow me on Twitter, (please do) then let me explain.

In the Emcomm thread, (a hotbed of seething, snarling, nastiness anyway) a relatively new ham asked a rather benign and open-ended question. Actually, it wasn't even really a question. He asked what tips and tricks more experienced hams had for someone just getting into emergency communications. He then subsequently got blasted for not using common sense, told to use Google, and was essentially called a moron for not framing his question correctly.

It made me angry, so I responded in kind. In hindsight, it probably wasn't the best way to deal with the situation, but it is what it is. I called out "the old guard" and said that they shouldn't bemoan the fact that no one with a newer ticket wants to come to meetings, help out at events, or activate rare DX when they are constantly barked at about the old days. I also pointed out that newbies rarely have the frame of reference to ask the "right" questions; whatever that means. Further more, the reason common sense isn't so common anymore is because hams weren't willing to give advice and make it common. Most of all, I told them that it was childish to treat people this way. 

My post was heated, and that wasn't good. Luckily K7RBW was kind enough to offer a constructive response that helped save the discussion from heading down the toilet. I also received a response from K1CJS that was well considered. There is a lot of information, both good and bad, floating around about any given facet of Amateur Radio. One has to narrow it down, or the answers are muddy at best. With that in mind and in the spirit of goodwill, here are the top ten lessons I've learned while using Amateur Radio in Public Service:

1.) Always have three ways (or more) to get power

Batteries run out, AA cells disappear quickly, the power grid is always spotty in an emergency, generators run out of gas. If you don't have redundant ways to secure power, your operation will suffer. Personally, I carry 5 ways to power an HT and 3 to power my mobile rig.

For the HT: I carry a fully charged battery in the unit and another in my go-bag, an AA cell holder, a cigarette lighter adapter, a wall-wart charger, and a fully charged 7.5aHr SLA battery with a 10 watt foldable solar panel.

For the mobile rig: 12v Power supply, a large 50aHr gel-cell marine battery, and two long extension cords, one for a 120v outlet and one with battery clips for the gel-cell or a car battery. 

2.) You NEED an LED headlamp with a spare set (or six) of batteries. 

You will need light, you will need your hands, and you may need your teeth at the same time…trust me on this one.

3.) Never go ANYWHERE on a deployment without:
  • ID
  • A copy of you Ham License
  • A copy of your ARES, RACES, or MARS ID
  • A multi-tool
  • Some duct tape (wrap it around an old Hotel card key)
  • A pencil (pens always fail on deployment, a pencil can always be sharpened with that multi-tool
  • Paper you can spare
4.) A small, cheap mag-mount is your friend

Stick it on a car, motorcycle, file cabinet, or cookie sheet and you've just doubled the power of your little rubber duck. When you forget it on said car, motorcycle, file cabinet, or cookie sheet, you haven't lost $130 on a Diamond 5/8 wave base antenna.

5.) 19" will let you talk pretty far

If you forgot your mag-mount antenna, broke it; or it just drove away on a car, motorcycle, filing cabinet, or cookie sheet, 19" of still wire (even a coat hanger) soldered to the center of a panel mount PL259 connector and one to four 19" radials attached mechanically or soldered through the screw holes make a pretty darn effective antenna. Check THIS out.

6.) Get your inner MacGyver on

You would not believe what that guy could do with a paperclip. Look HERE! Likewise, you would not believe what a little can-do attitude and brain-power can do to fix an otherwise dire situation. Hams are a very resourceful bunch. Don't give us a bad name by giving up when all else fails. A small container of random connectors, fuses, paperclips, zip ties, velcro, blah, blah, blah is a godsend in a pinch.

7.) Find every fuse on every piece of gear that you'll bring...

...now put twenty thousand of each one in your go-bag. Okay, twenty thousand my be excessive  but bring way more than you think you'll need. I've always found that I usually blow at least three until I figure out the problem.

8.) Sometimes being in Emcomm means taking out the trash

This one goes straight to my heart. You're their to serve the public, so serve them in whatever way is needed, when it is needed, for as long as you are able. If you are looking to play with your radio in a bad situation, stay home. Most of the time emcomm is about communications, but sometimes it's about taking out the trash. If you're not willing to do both, then your thoughtful support from home would be better for everyone.

9.) Be a part of the solution, not a part of the problem

Much like the last tip, when you are in a public service capacity, help out, with a positive attitude, stay out of the way, keep your nose where it belongs, and bring the gear and knowledge you need to take care of yourself for the duration of your service. The last thing anyone needs is a volunteer who was there to help suddenly needing rescue or a diaper change. 

10.) At minimum, carry three radios

You will obviously need your HT and or Mobile rig. In addition, I always carry a FRS/GMRS (make sure you are licensed for one), and a digital trunk-tracking scanner. Also bring the peripherals  manuals, power supplies, extra batteries, headphones, etc.. It always seems that someone in the command chain believes that FRS/GMRS and Ham Radio are one and the same. They will need you to relay communications between someone with one to someone with the other. Be a part of the solution and have one of each, so you can accomodate them. A trunk-tracking scanner is also nice to have, especially if you're savvy enough to program it on the fly. You will be able to monitor what is happening, who is coming, where the trouble is, and myriad other things.

THIS IS IMPORTANT: If you are scanning, do so through headphones. I carry a single surveillance-style ear-piece. Why? Because people will be listening over your shoulder. Chances are they are in the middle of the emergency and stressed out of their minds. They will read all kinds of things into the radio traffic and it will cause them more harm than good. Also, there may be information shared over the scanner that is more personal than during normal radio operations. It is important to let the communications happen without causing secondary issues.

These are the top-ten tips and tricks that I have learned while serving the public with my amateur radio. Whether you are supporting a run, bike ride, or full-scale city evacuation, I believe that these things will help you out. I hope they do.