Monday, September 28, 2015


I encountered this fellow, Tim Eldridge KF6TIM, at the Bungalow Heaven Neighborhood Association emergency preparedness fair, in Pasadena CA.  He is a relatively new ham, licensed about six years ago, who now holds his Extra class license.  He is involved with the Altadena Local Emergency Radio Team (ALERT) and CERT.  What he was doing at the event opened my mind up to myriad possibilities applicable to ARES, NTS and other emergency communications applications.

With a laptop in one hand and a Kenwood TH-D72A handheld transceiver in the other, connected with a USB cable, he is basically a pedestrian mobile packet WL2K station.  This radio has an on-board 1200/9600-baud TNC, along with GPS, APRS and other features.

With an after-market antenna on the Kenwood, he was able to connect solidly on 5 Watts,  with the 2-meter packet WL2K gateway KF6TIM-10, located 3.0 miles away, as long as he stayed away from the trees.  With a mobile or small base antenna, he certainly could have done better.

Imagine the possibilities!

NTS Info Table at SW Division Convention

The photo shows the NTS table at the ARRL Southwest Division Convention, Sep. 11-13 in Torrance CA.  Note the “traffic” cones!  We collected 15 radiograms, not as many as we had hoped.  But we did spend a good deal of time talking with the convention goers, and otherwise politicking.  We also had a "tech talk" presentation

Informational literature distributed by the Earthquake Country Alliance, which sponsors the annual Great California ShakeOut earthquake drill, stresses the family "out-of state contact."  That relative would be an information clearinghouse for the extended family, in case of a disaster.  Any family member in the affected area could call or text the OOSC, if that is possibly, or perhaps send a radiogram if it isn't, letting the family know information about their location, health, etc.

We suggested the following text:


But we did send a number of other individual messages as well.  We used a local mesh network to send batch files (ultimately by telnet) to the alternate RN6 MBO station in northern CA, and hence into NTSD.  The primary MBO station was without power at the time, and the operator both evacuated and deployed, on account of the Butte wildfire southeast of Sacramento.  The alternate MBO operator was "on a learning curve."  All out-of-the-area traffic eventually got out, however.  Some of it has even been serviced.  The few local messages that we got were delivered on the spot.

Traffic handlers who helped out:  Gary Wong W6GSW, Randy Branson WB6NCT, Clara Woll KJ6CNO, Jutti Marsh K6FRG, Grant Gemel KK6AHZ, Jim Lankford K6JGL, Rick Stutsman N6IET, Steve Brody N1AB.  The Pacific Area Chair Rob Griffin K6YR was on hand to help answer questions at the tech talk.  Thank you all very much!!

Friday, September 25, 2015

The Mirror in the Sky - part 1

The daily activity of the Sun routinely tosses electrons right out of the atoms in the upper atmosphere.  The free electrons (and remaining ions) make those layers conduct electricity.  For radio waves, this is like having a mirror in the sky, that can be used to bounce high frequency (HF, othewise known as short wave) waves over the horizon, to anywhere on the planet, if conditions are right.  These waves literally bounce off the sky & are known as skywaves


I had not been on the 80-meter CW traffic nets for very long, when it became obvious that sometimes I could hear the other stations and sometimes I couldn’t.  Unfortunately for me, these early months after my General license were during the sunspot minimum.  Some days I would bring up for a look-see & I’d find myself dusting off my computer screen in order to find out if what I saw on the solar image was a sunspot or a piece of dirt!  At that time, the proportion of “dead nets” was, to say the least, higher that usual.

The local 80-nets are NVIS nets … Near-Vertical Incident Skywave.  The outgoing wave from the transmitter hits the ionosphere from a near-vertical direction & is reflected straight back down, illuminating the area within a few hundred kilometers, which is just the area that a local or Region traffic net is looking to cover.

It should, in my na├»ve & innocent mind, then be easy to see if the net was going to work or not by lookup up (on the internet) the daily predicted value of a number called foF2.  foF2 is the critical frequency (f) for the “ordinary” (o) wave reflected off the F2 layer of the ionosphere, for a vertical ray path (i.e. NVIS).  There is also an fxF2, relating to the “extraordinary” wave, but it seems that FoF2 is the standard number used to indicate the health of the ions in the upper atmosphere.  (The ordinary & extrordinary are circularly polarized in the opposite direction, but otherwise … well, the same?  A dipole antenna, such as used by hams, only gets half the energy contained in either, but cannot tell the difference.)

Below the critical frequency, the wave is reflected back.  Above it, the vertically traveling wave flies off into space & is gone.

There are web sites out there that give the current predicted foF2, based on detailed ionospheric models (including current values of sunspot number, solar flux, etc.).  Before each net, I note down the predicted foF2, then turn on the radio.  If the net is on 3.537 MHz & foF2 is higher than that, then (assuming the D layer isn’t still too strong … the D layer goes to bed about sundown), I should be able to hear the other stations on the net.  Unfortunately, the source web sites do not all agree with each other, any more than any two weather forecasters would agree.  This muddies the situation.

When the ionosphere has gone south for the winter (leaving us only a few ions) & the Sun is not very active, the 80 meter ham band is right on that hairy edge with the foF2.  Often, as you would expect with critical reflection, the nearby stations drop out, because the ionosphere isn’t strong enough to support truly vertical NVIS, while the stations a few hundred miles away will still come in.  Sometimes, we all may as well pack it in & go to bed.  And, sometimes all is hunky dory.

So picture this … a relatively new ham, who keys & writes with the same hand, struggling with CW (Morse code) in the first place, still having to write down every single character to follow what is going on, now also trying to keep notes on everyone else’s signal strength!  It got better, but it did take quite a awhile!

Naively, I expected 80 meters to behave in a similar way to the higher-frequency ham bands that are normally used for contacting distant (DX) stations.  For any given great-circle path, there is a LUF, or lowest usable frequency, determined by the D layer, and a MUF, or maximum usable frequency, determinde by how good the ionospheric mirror is between here & there.  These are the principles of radio propagation that are taught in the amateur radio license study manuals. In the case of the “low bands” (80 meters & 160 meters), the pattern is sort of followed, but not all that well.  Immediately, I noticed some wide discrepancies.  Two different web sites listed foF2 values that differed by up to 1 MHz.  Since the CW end of the 80 meter band is at 3.5 MHz, that is a 29% variation, which seemed like a lot to me.  Often the nets worked when they should not have & vice versa.

One of our nets, the Sixth Region Net, called RN6, has two sessions every night, one at 7:45 pm Pacific Time & one at 9:30 pm.  The second one should be tougher copy than the first one, right?  Because the Sun isn’t shining on our part of the upper atmosphere, most of the electrons would have found their way back into an atom.  Maybe, maybe not.  It depends, apparently.  Occasionally, the second net was the better one.

Even crazier, on rare occasions, I ran into a net called NYS on the RN6 frequency, 45 minutes before ours.  It was weak, but I could copy it well enough.  I also checked on the internet for the time & frequency.  NYS is the New York State traffic net!  80 meters is not supposed to have that much range.

So there is weirdness going on over our heads, that only short wave operators (hams or otherwise) know & care about.  That’s about where my understanding stayed until I found this (Eric Nichols clued me in to it) …

There various scientific installations around the world that probe the ionosphere, every 15 minutes!  Many of them post their results on the web.  The closest ionosonde station to me & the rest of SCN & RN6 is the one at Point Arguello CA (Vandenburg Air Force Base, actually).   The ionosonde sends pulses upward, while sweeping the frequency through the entire relevant range, normally 1 MHz to 15 MHz.  It is just like any other radar … the reflections that come back tell is what going on & the time delay tells how far up the action is.  It use circularly polarized antennas, so can tell the difference between an ordinary & an extraordinary wave, which the output indicates by color.

In fairly normal circumstances, the results look like this:

The horizontal axis is frequency in MHz & the vertical axis is reflection height in kilometers, as determined from the time delay between the pulse & its return.  Pink/red = ordinary wave.  Green = extraordinary wave.  Note that above about 7.8 MHz on this ionogram, there is no ordinary return.  This frequency is foF2.  The computer pins it down to 7.838 MHz (see upper left).  You can also see a reflection from the F1 layer here (below 4 MHz) & some E layer reflection (below 2.9 MHz), but that would constitute a “plot complication” for this post.  The black solid & dotted line is the computer model’s estimate of the ion density as a function of height.
Now, this is important!  Are there really two F2 reflecting layers, one around 300 km & one around 600 km?  Nope, there is only one at 300 km.  The other one is the same wave that reflected down from the F2, hitting the Earth’s surface, going back up & bouncing back down again.  This indicates a moderately good mirror.  We can count the number of multiple reflections & use that as a guide to how strong to expect the net signals to be.
So now I don’t need to depend on forecast models.  What I see on the Point Arguello ionosonde site is the real, actual foF2 at the time.

Now I am able to answer one of my original questions:  are the disparate predictions really that far off?  The quick answer is Yes.  Using data from mid-July 2015 to mid-September, I see that there is apparently quite a lot (one sigma on the difference O-C is 0.75 MHz during RN6/1 and 0.89 MHz during RN6/2) of variation in the ionosphere that is due to factors not accounted for by the model (such as maybe geomagnetic activity?).  These two diagrams show (in blue) the observed ionosonde foF2, as a function of what one of the models predicts and (in orange) the difference (observed minus calculated).

During this particular two-month period, there also seems to be a systematic difference.  During RN6/1 the real ionosphere better than the model by mean value of 0.39 MHz, or a median of 0.25 MHz; the difference between mean and median indicates there are more outliers on the high side than on the low side.  During RN6/2, the mean difference is even larger (mean 0.60 MHz & median 0.50 MHz).  The real ionosphere performed better than the model, especially during the second session (RN6/2).  I’ll be interested in watching it through the winter & spring, to see how this situation changes.

All this goes to show that there are some wonderful scientific data out there on the Information Superhighway to play with.  You don’t want to be shy about enjoying it!

The model that was used for this project is the “effective sunspot number” model used by DX Atlas software ( .  I picked it for the simple reason that it is the easiest to use & does not involve reading value off a tightly spaced chart.

In my next installment, I will write about how to read the ionograms, a process which I am just learning.  Just let me say, though, that (as one of the southern CA DRS stations), I am almost at the point of being able to look at the web & tell whether or not I’ll be able to get my NTSD MBO connection or not.  So, stay tuned (so to speak).

Wednesday, September 23, 2015

Wow!  It has been a year and a half since I posted anything here!  What has happened in my life since then?  The biggest change is that I retired at the end of January, this year.  That means, among other things, that I am for the most part getting adequate sleep.  Also, I wear shorts, a T-shirt & zoris most days, which is very positive.

I am even more heavily involved in amateur radio than I was, especially the “note passing” aspect known as the the ARRL National Traffic System (NTS).  That refers to message traffic, not to cars & cones.  Since the rise of the Internet, interest in NTS has been on the decline.  Our emphasis these days is on emergency preparedness (when Gore’s marvelous invention might not work) & helping to train hams interested in emergency communications, as opposed to sending birthday radiograms to Aunt May back east.  I would not be surprised, however, if hams didn’t see an upswing in NTS activity in the not so distant future.  We got a nibble of interest from high places (FEMA) for us to participate in an upcoming drill, precisely because we are (understaffed but) organized & can move messages around the US without the power grid, the phone system, or the internet.  A nibble is just that, a nibble, but it has spurred somewhat of a self-start to let ourselves be known again & recruit more hams to participate.  There will be more of this on my blog.

Some articles from the NTS newsletter “QNI” may also be reprinted here.  QNI, by the way, is the call for operators to check into a CW (Morse code) net.  The newsletter is distributed by forwarding on various yahoogroups & other lists; the web site ( does not seem to be keeping the archive up.  I’ll need to look into that.

I also still live with a small pack of two dogs.  The eldest is Lopo (officially Dublin, but affectionately named after a sci-fi character Lopo the Lupecko), the world’s dumbest but definitely most affectionate Border Collie.

The more recent addition to the pack is Jansky (because she has very big ears).  She is Queensland Heeler (AKA Blue Heeler AKA Australian Cattle Dog).  She is smaller & lighter than her breed standard, but definitely up there in the brains department.

That’s it for now.  I hope to keep my readers informed & entertained.

Thursday, March 7, 2013

Some Seismological Humor

Came across this list, which was created by a bunch of us, probably in the 1990s sometime.  You can see by some of the technological references that it's no longer current.


If your friends & acquaintances get panicked looks on their faces whenever your pager goes off ...

If you have ever eyed your watch during a damaging earthquake to get the S - P time ...

If your off-the-cuff magnitude estimate of said quake is less than 0.3 different from the final number ...

If you have ever felt a 1.8 ...

If you have ever driven off the road or caused a traffic accident while gawking at a fresh fault scarp ...

If unreinforced masonry, even on the East Coast, makes your skin crawl ...

If you seriously try to avoid stopping under (or on) freeway bridges ...

If you avoid parking structures (& apartments with parking underneath) at all costs ...

If you know the location of places like Agadir, Spitak, Chichi, Parkfield & Loma Prieta ...

If you continually get thrown out of yoga or taichi class because your pager will not stop going off ...

If you have ever take a laptop computer/cellular modem into a movie (or the grocery store) with you ...

If you have ever given directions like "Cross the San Andreas, then turn left on the first street" ...

If you have ever told someone not to worry about that big quake in southern Nevada, that it is "only a nuke" ...

If you can discuss the propagation of Love waves with a straight face ...

If you have an indoor windchime ...

If you have ever waked up from an earthquake dream & logged in to the office, just to check that it wasn't real ...

If you have ever operated seismographic equipment anywhere in your house ...

If you choose to live in a particular area because it has earthquakes ...


Thursday, January 3, 2013

I've written a few times on this blog about the joys of learning CW (Morse code) at an age more andvanced than the teens.

I've never been all that interested in psychology or neural science, but I have come across some weird surprises along this journey.  For example, over the Christmas holiday, I started wondering whether I could learn to send code with my left hand & if so, how fast.  I am totally right handed & cannot make a legible scratch with my left hand, but I can use a computer mouse.  It's a little bit slower, but it works & it got me through a period of problem with repetitive motion syndrome once.

As a quick test, I turned my Touch Keyer (a good stand-along practice device which is much less forgiving than a standard keyer/paddle) upside down. That way the thumb was still on the dits & the index finger on the dahs.  I started off at 5 WPM & worked my way up to about 18 WPM.  This is only slightly below may normal right-handed "cruising" speed!  I made a lot more errors with my left hand & I "got confused" more, but it worked a lot better than I thought it would. My hand felt totally awkward, but the sound was pretty much right & no worse than my right hand was a year ago at that speed.

Then I discovered that, if I thought about the mechanics, I lost it.  I did a lot better when I just thought about the sound of the characters.  So ... the right & left hand seem to be "cross-wired" better than I expected, but apparently not through the concious parts of the brain!

It is close enough that practice might actually be worth the time.  If I could operate the key left handed, then I could keep my log right handed, etc.  No need for delay on the net while I picked up or put down my pen.  For the future ... As I said once before, it's interesting watching the brain bitch & moan while it learns.

Meanwhile, I cannot "cruise" at 21 WPM every day.  Some days it's easy & some days it's hard.  Some days I have to slow down.  I make errors at any speed (but different ones, having to do with timing & lack of coordination, mostly).  Some days I can hardly do anything right.

I think this has to do with stress (from any source).  I cannot send well, or run a net well, for that matter, if I'm having an anxiety attack.  Nets themselves can be very stressful, depending on who's checked into them & on what the ionosphere is doing.  If something doesn't go well, the stress gets into a positive feedback cycle with the sending errors or other confusion & it's all downhill from there.

I think this is the key (so to speak) of why this activity reminds me of "Zen & the Art of Archery" or whatever that title was.  It's really a mind game, within my own head.  I do have to remember how to spell a word conciously, if it's a long one, but beyond that, there needs to be no concious thought between the visualized letters & the sound that comes out of the monitor (& if live, the signal that goes out to the antenna).

I know the antidotes to this, just have to use them more.  One is practice. One involves visualization & another involves a zafu.

Maybe there is a reason why I catch myself expecting certain people to address me as "Grasshopper"!

Monday, October 15, 2012

K6HTN's Excellent Adventure

I spent the weekend at the ARRL Pacificon Convention in Santa Clara.  Pacificon is always a good hamcon & this year it was also the ARRL National Convention, so it was doubly so.

There were several highlights, of which this is only one.  I got to operate K6KPH, right there from the hallway of the hotel.

K6KPH is the amateur station operated by KPH ( , the old Marconi/RCA ship-to-shore Morse code station.  KPH itself operates (at least) once a year on July 12th, "Night of Nights, when they commemorate the final commercial Morse operation in 1999.  I think I may have an earlier blog post about Night of Nights.  KPH is a historical monument on National Park Service land (Pt Reyes National Seashore).  The equipment has been restored & is operated by volunteer members of the Maritime Radio Historical Society.  KPH ops have commercial radiotelegraph licenses, but are still volunteers.

They operate the amateur station every Saturday & on special occasions, using the commercial transmitters at  Bolinas scaled back to the 1500 Watts legal for ham radio & using the big commercial rhombic antennas.  From Pacificon, they operated the Bolinas transmitters by remote link, while using a dipole receive antenna on the roof of the hotel convention center.  It was an interesting situation, since the transmitter could be heard literally anywhere in the world where the path was open (the ionospheric conditions were right) & quite loudly!  But the receive station was like your average amateur station, they may or may not hear the stations who answer them.  Also, the transmitters are crystal controlled, on the CW calling frequency & not able to move around the band.

When I got there & was wandering around the vendor area, I talked to Richard Dillman K6KWO (nemonic Kilo Watt Output?) & he urged me to "sit the circuit" for awhile.  I had quite a lot of trepidation - after all, the entire world would be hearing my keying mistakes! - but finally decided that it was one of the things I definitely wanted to do at the convention.  I sat for a few hours on Saturday afternoon, using a vintage J-38 straight key that was provided & the old style headphones that block out no external noise at all.  I did have some problems, not the least of which was that I'd never seen the receivers (there were three) before & didn't know how to adjust the volume.  At one point someone answered who was too loud & I just moved the headphones from my ear to my cheekbone.  In the process, one of them got turned around, to annoy the rest of the folks present.  I got a bit of ribbing about that later.

I got several QSO's on 15 m, some of which were quite long, because I had to explain why the transmitter was in a different location (QTH) than the receiver & why I could not hear them as well as they could hear me.  Talked to one guy in TX who answered me a second time later on, just to ask my personal callsign, so he could look up my email address & send me an mp3 file illustrating just how strong my signal actually was! I also had a DX contact from Barbados (prefix 8P6).  At least I thought he said Barbados.  He was pretty  weak (229).  After that was done, I walked over to the Northern CA DX Club table across the hall & confirmed that Barbados was indeed 8P6.  So these guys are in the log & if they want QSL cards, they need to contact the Marine Radio Historical Society as listed under K6KPH in

After awhile, the too-loud Morse code assaulting my ears & perhaps some stress caused my allergies to act up & my ears to clog up.  At about that time, they decided to start giving me a light-hearted hard time about my backwards earphone.  I'd had enough for one day.  I'm seriously thinking about making a trip up to Pt Reyes (the normal receive site) in the winter, however, so I can sit their regular amateur circuit, using my own bug key & headphones & get a tour of the KPH installation.

I asked to send a radiogram to our Los Angeles Net net manager, who was not able to attend Pacificon.  This is the form that they gave me!