AmateurRadio.com

What do you do to complete these hamfest bargains? 3D printing for the win!

The best thing about it is that you can color-code the connectors, too! Finally, props to a CAD-ninja coworker for whipping up the beautiful SolidWorks model in a couple of minutes.

“One man’s signal is another man’s noise,” began Dr. Kudeki as he derived incoherent scatter radar theory from Nyquist’s noise theorem in ECE458.  I think of that statement often, whether it be QRM on the ham bands or sifting through the pocket litter of web users looking for their consumption preferences.

This morning, I admired just such an example of signal and noise while watching the NOAA Doppler weather radar.  Undesired targets of a radar that return echoes are termed “clutter” in the radar parlance and one simplistic way of eliminating clutter, especially when you expect the desired scatterers (“targets”) to move, is to assume that all of the stationary returns are clutter.  In the weather radar, we get clutter from all sorts of stationary things like trees, hills, and buildings.  Of course, what causes the clutter to move?

You see, it was one of those humid August mornings when a ham’s mind wanders to…tropospheric ducting.  Yes, indeed the clutter returns were moving, intensifying before and after sunrise.  I was fixated on this and watched the loop over and over again before noticing an even more interesting bit of clutter!

Beginning at 0958 UT on 4 August 2014, there is a small ring forming out over the Elk River area.  The ring, which is indicated by the downward-pointing vertical arrows, expanded over the next >40 minutes.  I was puzzled and watched the loop over and over.  I considered and discarded a number of theories before resorting to Google.  Apparently, it’s very likely a flock of birds.  Sure enough, the epicenter of the ring is Elk Neck State Park.  Fascinating.

The slanted arrows in the figure above indicates the ground clutter that I was originally noticing as a signature of tropo ducting, obviously now of secondary interest in this sequence of images!

Epilogue:  I sent these frames to my father, who is an avid observer of the natural world.  He passed them along to two friends back home who are birders.  At press time, one reported that he had learned of these “bird circles” from Greg Miller, another birder from the area who got famous as one of the subjects of the book (and movie of the same title) The Big Year.  I haven’t read/seen it, but I guess they went to Adak, which has a special place in my heart.  Anyhow, it’s a funny small and interesting world in which we live.

Three perhaps noteworthy amateur radio activities occurred recently around K8GU: 1. During the course of some HVAC upgrades, I was able to get two holes core drilled through the foundation to bring coax and control cables into the house; 2. I operated in the NAQP August CW contest; 3. Evan and I went to the Berryville, VA, hamfest.

These two ports exit the basement into a crawl space where I will ground the cables before they enter the house.  I still need to get some hydraulic cement or other quick-setting patch mortar to clean up the drill crater on the outside.  Total cost: $5 in materials and a large pizza for the crew.

Screenshot above shows TRLinux after the end of the contest (obviously it was today, not last night).  TRLinux performed flawlessly again with the YCCC SO2R+ box driving the KK1L band-decoder and 6×2 switch.  I operated for about five hours (probably a little more, and definitely more if I used the NAQP 30-minute time-off rule to calculate it).  I got up after my first operating sitting at the beginning of the contest and left the shack.  As I exited the door, I was hit with the smell of hot electronics.  You know the smell: like when you just let the smoke out of a transistor.  I walked over to the antenna switch matrix where I was using a triplexer to split the hexagonal beam to both radios.  It was warm to the touch.  It seems to have continued to function, but I’ll have to disassemble it at some point to see if any irreversible damage was done.

The August NAQPs are always fun for us out East because there is the ever-present opportunity for sporadic-E throughout the contest, giving us a chance to work nearby states, which can really drive up the multiplier (and QSO, depending on the direction of the opening) total.  Of course, this is the real boon of having a second radio: you can call CQ on your most productive band while looking for openings on the others.  I came down after supper with the family to “work 40 meters before it goes long” and ended up with blistering 10- and 15-meter runs into the Midwest and South.  Since Evan and I were planning to go to the hamfest and I don’t yet have a 160-meter antenna at the “new” QTH, I pulled the plug at midnight local time (0400).  Not sure 40 meters was even getting long at that point.  At any rate, it was wonderful to say “hi” to so many old friends from MRRC, MWA, SMC, PVRC, and beyond!

A final comment:  You can really tell how much better one radio is than another when you have them both side-by-side on your desk.  This was quite apparent when I had the K3 and the TS-930S and it is also apparent with the K3 and the K2.  The K2 is a wonderful radio and fun to operate, especially in the field, but it’s not the K3 as far as fit and finish, among other things.  No, I’m not buying another K3 anytime soon.  The K2 is quite enough for the second radio.

I’ve always heard that the Berryville, VA, hamfest had a good boneyard/fleamarket/swapmeet but I’ve never managed to attend.  I resolved to attend this year and was pleasantly surprised.  Evan came along for the ham-and-egg breakfast, which was good but he rejected the ham after only consuming about 1/3 of it, and a trip to the playground at the school across the road.  This is still a “real” hamfest like the ones I remember going to in the early 1990s before eBay and online trading really took the wind out of swapmeets.  There were plenty of rigs spanning the spectrum of boatanchor to relatively modern, HF and VHF/UHF.  There were lots of amplifiers, as well, (and a small quantity of CB junk; Texas Star, anyone?)  There were also lots of antennas, and even some Rohn 25.  The computer and cell phone accessory dealers were mercifully few and there were lots of tables of parts, bits and pieces.  This is a ham’s hamfest and I’ll be returning.  I picked up a bunch of Cinch-Jones plugs and sockets for my new cable ingress, plus some SMA connectors and flexible coax jumpers.  Plus, I ran into a few friends, although not the ones I expected to see!

I’ve been attempting to get my arms around my various logs from different callsigns. Previously I have had mixed luck with LOTW. Then I pretty much abandoned it. This time I read and re-read the instructions. Today I got my TQ6 file and was off an running.

I exported my current log from fldigi as an ADIF file and then used the TQSL application to upload it. Error, error, error. What was this? I hit Google and started researching:

ARRL’s tqsl messes with fldigi saved QSO_OFF time
I learned more than I wanted to know this morning about what the ARRL¹s tqsl application for LoTW does when it signs your saved fldigi newlog.adif file. It does more than just applying your digital signature. I had a busted QSO with Jeff, N8NOE, on LoTW and spent some time trying to understand what happened. The problem was with the time of the QSO. Both of us log the time at the the end of the QSO; however for there was a disconnect because my QSO time at LoTW showed up as Time ON, rather than Time OFF. Fldigi logs both TIME_ON and TIME_OFF; however, when you ask the ARRL tqsl application to apply your digital signature, it ignores the fldigi saved Time_OFF and converts the TIME_ON to a nonstandard ADIF format called QSO_Time. If you want your fldigi logs uploaded to LoTW to reflect QSO OFF time, you have two options. You can manually edit your On and Off times in Logbook-newlog.adif panel read the same. Another workaround is to use the fldigi File/Export ADIF with the option for Time ON unchecked. Then use a text editor to search and replace TIME_OFF with TIME_ON. This will fool the ARRL tqsl application to log the correct correct QSO time. Another option for someone to think about could be a new macro command that would reset the QSO times (ON and OFF) to be the same when you click on log. If you don¹t believe tqsl changes your fldigi logged QSO TIME_OFF, open one of your last .tq8 files with text editor (I use BBEdit) and scroll down and you will note the nonstandard QSO_TIME time that matches your your ADIF TIME_ON rather than TIME_OFF. 73 Dick AA5VU

… and that is what I did. And it worked! Although the issue Dick describes and the issue I was having were different, the solution still worked.

Now I am trying to add the logs for both my YI9MI and HL9MI operations. We will see how that goes.

There is good news in the blogosphere! Jeff Davis, KE9V (ex-N9AVG, WD9GCT), has re-established a blog and is now posting regularly. There is no doubt I am an avid fan of Jeff and it is always interesting to watch his online permutations. For a very long time he had a well established blog at ke9v.net. Yes, he frequently rebooted the blog and Jeff is not an online pack-rat. His blog reboots always cleaned away old posts to make room for the new. I encountered many of his short stories, ham radio based. From time to time, he would post the stories on his blog or put them into a post. 1,000 Marbles is the only one that I know of that is published as a book. I also believe that many of his stories were translated into Japanese by Leo, JJ8KGZ. I hope that with this reboot Jeff might again share some of these stories, or perhaps a new one? Or, I would ask him to publish his stories as a collection. I am sure many hams, like myself, would purchase a copy.

Jeff also has been prodigious in producing engaging podcasts. Starting in ~2005, Long Delayed Echos featured over fifty episodes that delved deeply into the roots and history of amateur radio. Cornbread Road was another of Jeff’s podcasts. This 13 episode podcast (and an additional epliogue) not only highlighted Jeff’s talent in crafting ham radio based fiction, but also his storytelling abilities.

Jeff always pushes the capabilities of social media. He regularly uses twitter. After dabbling with Google+, Jeff took the plunge. He discontinued his blog and used Google+ to make frequent posts. Then, not that long ago, came Quintessence, a weekly email. Archives are available here (http://tinyletter.com/ke9v/archive). I personally believe this would make for a great, weekly RTTY bulletin. Far more interesting than the ARRL’s. Perturbation is the name of the latest reincarnation of his blog. He always manages to select interesting titles for each of his blog’s incarnations.

per·tur·ba·tion – a deviation of a system, moving object, or process from its regular or normal state of path, caused by an outside influence.

Bottom line – I am glad to see Jeff’s blog back up and hope it continues for some time. But, as Heraclitus of Ephesus says, “Everything changes and nothing stands still.”

Mention Health and safety and its likely you think of some Muppet decides that children need a suit of armour to play conkers (for those not lucky enough to have tried to make a horse chestnut seed the hardest material known to man, have a look here). Back to the point. I’m talking about looking after yourself in your hobby.

Ham radio has some pretty high hazard activities. High voltages, antenna’s on towers, climbing on roofs etc. Recently I’ve been soldering a bit more. Whilst its not likely to be particularly harmful to occasionally sniff in some fumes its probably not going to do me much good either. So I might benefit from a solder fume extractor.

I understand that the technical terms (and we all love a technical term) is local exhaust ventilation or LEV. Still doesn’t sound too complex and thankfully it doesn’t need to be. A fan that sucks and a filter is pretty much all you need, it seems. So do I really need an industrial scale extractor? probably not. So as an experiment I’ve bought a £5 extractor from eBay.

Its an mdf laser cut body with a 12v (computer?) fan. It takes 5 minutes assemble and may or may not need some PVA to hold it all together. I say might as mine was a good tight fit so probably won’t need it in the short term but as it gets bashed about on the workbench it might need some help to stay together.

The extractor is basic (what do you expect for £5) and didn’t come with any filter media. So a suitably sized filter will be needed. Perhaps the same activated carbon you get for cooker hoods would suffice, will need to be sourced. I dare say just sucking it from one place to blow to another isn’t really helping matters.

I could measure flow, compare against standards, determine filter abatement. I say could, because clearly this hasn’t been designed with that in mind and how would that really help? The video below shows you how effective it actually is.

So the conclusion. The hazard associated with occasional solder fumes is probably quite low and the risk is also probably quite low. But a simple device, like this, has the opportunity to remove the fumes from the workbench and at the very least stop them going in your eyes. That can’t be bad.

Here it is in action. Distance between tip and fan is approximately 10cm.

p.s. If you’re really lucky you can hear my daughter homebrewing in the background (what she is homebrewing is anyone’s guess)

Locators, or as us Brits call them, Maidenhead locators. Named after a town in Berkshire that isn’t close to the meridian but held a meeting by a bunch of VHF chaps in the early 80’s. In fact the now de facto method for looking something up (Google & Wikipedia) give us:

‘The Maidenhead Locator System is a geographic co-ordinate system used by amateur radio operators. Dr. John Morris, G4ANB, originally devised the system, and a group of VHF managers, meeting in Maidenhead, England in 1980, adopted it. The Maidenhead Locator System replaces the older QRA locator system with one that is usable outside Europe.^[1]

Maidenhead locators are also commonly referred to as QTH Locator, grid locators or grid squares, despite having a non-square shape on any non-equirectangular cartographic projection. Use of the terms QTH locator and QRA locator was initially discouraged, as it caused confusion with the older QRA locator system. The only abbreviation recommended to indicate a Maidenhead reference in Morse code and radio teleprinter transmission was “LOC”, as in “LOC KN28LH”’

But more to the point how do you calculate one? Easy if you know Perl (apparently – thanks again Wikipedia)

#!/usr/bin/perl -w
# (c) 2012 Chris Ruvolo.  Licensed under a 2-clause BSD license.
if($#ARGV < 1){
  printf("Usage: $0 <lat> <long>n");
  exit(1);
}
 
my $lat = $ARGV[0];
my $lon = $ARGV[1];
my $grid = "";
 
$lon = $lon + 180;
$lat = $lat + 90;
 
$grid .= chr(ord('A') + int($lon / 20));
$grid .= chr(ord('A') + int($lat / 10));
$grid .= chr(ord('0') + int(($lon % 20)/2));
$grid .= chr(ord('0') + int(($lat % 10)/1));
$grid .= chr(ord('a') + int(($lon - (int($lon/2)*2)) / (5/60)));
$grid .= chr(ord('a') + int(($lat - (int($lat/1)*1)) / (2.5/60)));
 
print "$gridn";

But what happens if its all Dutch to you (It is to me)?

Well I put together a simple spread sheet that does the calculation. Its nothing special but deciphering what several different people have put into explanations that include adding your birthday, taking away your dogs maiden name and that kind of thing. Hopefully it’ll help you understand where those numbers come from and how to calculate them. So help yourself and if it doesn’t work then fix it and share it ( I tested it with 3 locators and lats / longs and it seemed to work). I also learnt a few more things about Excel so its all handy.

Here it is then