Great Circle Map Generator

For those of you that are interested in radio listening, particularly over long distances (AKA DXing) with even a moderately directional antenna, having a great circle map projection for  your location is a necessity.  Looking at a Mercator Projection, the normal “flat” map most are familiar with, one might come to the conclusion that due west from upstate NY lays the Washington/Oregon state boarder.  Appearances can be deceptive, bearing away at 270 degrees true (due west) from upstate NY is the California/Mexico boarder.

This is because the we live on a big sphere.  In this regard, the only place the the Mercator Projection is accurate is around the equator unless one is going due north (0 degrees) or due south (180 degrees).  The further north or south from the equator, the less accurate a flat map is.   Therefore, having a Great Circle map projection based on your location is handy for choosing the right azimuth to listen along.

As with many things, the internet provides the required tools to generate a great circle map for any location in the world.  The first thing needed is an accurate fix of your location.  This can be obtained via GPS, or, if you know how to look at a map and or satellite picture, itouchmap can be very useful.  Once you know where you are,  you can plug that information into this Great Circle Map Generator.

I saved the image as a bit map and use it as the wall paper on my computer.  That way, I just need to minimize any running programs and I can see what the correct azimuth is to any place in the world.  This is for upstate NY:

great circle projection
Great Circle Projection

The first aid kit

One of the things that was drilled into my head when in the military was first aid, which we were all required to learn. Those of us that worked around high voltages were also required to know CPR, including passing the American Red Cross CPR course.  I have used CPR on three separate occasions, none of the victims lived to tell about it.  I have been told by my wife’s cousin, who is an ER doctor, that that result is fairly typical, especially in older persons with heart conditions, which in two instances was the case.

I have always carried a standard first aid kit in my truck.  Things like band aids, gauze pads, sterile water, Hydrogen Peroxide, medical tape, splints, antimicrobial cream, blankets, etc.  Nothing hugely complicated, something like this unit.  I have used it recently at accident scenes, which I tend to stop for if it looks like they need help.

Philips Heartstart onsite AED
Philips Heartstart onsite AED

To complete this, I have also purchased an AED.  As one medic once said, if a heart gets shocked out of sinus rhythm, it can be easily shocked back into sinus rhythm provided it is done quickly.  Working on high voltage power supplies always entails some risk, even when all safety procedures are followed.  As little as 60 mA can cause arrhythmia.  Dry skin has a resistance of about 300 ohms, which means that 180 VDC is the threshold for fatal shocks.  This value is much lower if the skin is wet. Any shock received through either hand is likely to travel through the chest and can effect the heart.  Many of the transmitter sites we service are remote, medical help may be 30-60 minutes away under good conditions.  Having an AED on hand is just a little bit of extra insurance, that will hopefully never have to be used.

CPR procedures have been updated in the last few years, if one has not recently reviewed them, it might be worth while to take a refresher course.  I will say, hands only CPR is an improvement not only because it is more effective, but also because most heart attack victims vomit and loose control of their bowls.  Reduced contact with someone else’s stomach contents is always welcome.  This AED came with a training video CD.  While AED’s are designed to be intuitive, having training on their use is always a good idea.  The Red Cross also gives classes that include the use of an AED with hands only CPR.

Merry Christmas, et. al.

I have looked at my personal schedule, it is likely to be very light blog posting over the holidays as I am booked, booked solid I tell you.  So, if I don’t get to say it, Merry Christmas, Happy Chanukah, Happy Festivus, Happy Saturn Festival, Happy Druid dirt munching dancing naked under a full moon, or whatever it is you celebrate.

For my part, it has been an interesting year.  It started out a little trepidus, what with my full time job being eliminated in January.  I was fortunate to be re-employed part-time right away, many don’t get that luxury.  Then, my wife returned to teaching full time, which made me, by necessity, a stay at home dad four days a week.  There have been many changes, but in the end, everything has worked out rather well.

While at home, I have worked on the blog and other ways to earn a little extra money.  I can say that I am genuinely surprised by the reception this blog gets, both in the comments and off line e-mails and phone calls.  I have enjoyed interacting with other industry professionals and bystanders, and although I might not agree with everyone on every point, I respect you all and value your input.  I have found that while my engineering work hours are reduced, the amount of raw material for blogging is also reduced.  I have also found that 14-15 posts per month is the right balance between quantity and quality, with the later being foremost importance.  For as long as I have quality raw material to work with, I will endeavor to write about, take pictures of, and research issues that involve radio broadcasting.

Next year will undoubtedly bring about more changes.  I look forward to hearing from you and I wish you all well over the holidays and on into the New Year.


This is what you’ll get…

Back many, many years ago, in a city far away, I was driving down the road and I flipped one of “my” stations on the air.  The end of this song was playing:

The ending sounds an awful lot like a Moseley MRC-16 transmitter remote control’s return telemetry.  When I heard that on the air, my first response was “HOLY SH*T! The telemetry is on the main channel!”  A little voice in the back of my head said “That is not possible.  How is that possible?”  I grabbed the gigantic, then state of the art Motorola bag phone and dialed the studio hot line, just before I hit the  “send” button, the song faded out and the announcer came on back selling “Karma Police by Radiohead

Wow.  Radiohead?  Karma Police?  WTF?

I almost had a coronary.  When I got home, I tried explaining this all to my then girl friend, who didn’t get it.  Few do.  At the time, making such an error would be very bad form indeed and likely open the unfortunate party to all sorts of snickering and finger pointing at the next SBE meeting.