Sunday, March 12, 2017

Summits on the Air - Mountain Goat Award

When Heinrich Hertz proved the existence of electromagnetic waves, they were thought to behave like light (travel in a straight line), thus precluding the possibility of using them for long distance communication (more than 12 miles or so). Marconi thought otherwise. Over one hundred years ago, Marconi defied all expert opinion as well as common sense by proving that electromagnetic waves at certain frequencies will follow the curvature of the earth. He shared the 1909 Nobel prize in physics for this discovery. His technique was to use more and more power (15 kilowatts), longer and longer wavelengths (365 meters), and bigger and bigger antennas (huge wire arrays 100's of feet high) to extend the range of his signals,. On December 12, 1901 he successfully spanned the Atlantic "sparking" the electronics age we live in today.

SOTA activators on summits around the world. continue to stretch the bounds of Marconi's discovery of ionospheric propagation by using flea power, short waves, and small antennas to contact chasers thousands of miles away.

After 150 summit activations, about 3,000 two way contacts and 1000 activator points, I finally became a SOTA Mountain Goat. I just received this beautiful trophy from England which I will proudly display. This challenge entailed round trip signals to New Zealand, Spain, Japan and England from Colorado with 5 watts (the power of a flashlight) and 50 feet of wire! Here I am in contact with England from the 14,276 foot summit of Mt Antero (right photo).

Mt Antero

Saturday, March 11, 2017

"Weightless" Elecraft KX3 or KX2 microphone for SOTA

I operate mostly CW on my SOTA outings, but I always take this light weight mic along since it's built into my earbuds. This is just a standard smartphone ear bud/mic with an adapter that was intended to allow connection to a computer. Turns out that the earphone and mic jacks on the Elecraft KX2 and KX3 are compatible. To transmit, use VOX, or PTT with the XMT button. Note the essential windscreen. This was made with earbud foam hot glued to the mic housing. Keep the glue away from the side with the mic hole.

Friday, March 10, 2017

SOTA Spotting with the Yaesu FT-1XDR

The Yaesu FT-1XDR is my go to readio for SOTA activations. I mainly use it for APRS spotting to the SOTA spotting system and it works great. The only problem was that I fumbled around in the cold trying to enter the spot. So, I found a way to store, modify and repost old spots. Here's my boring youtube how-to video, if you really have to know....

I use Google Sheets for my SOTA logging software.  It automatically keeps a cloud backup for me and it easily and quickly provides a CSV file for upload to the SOTA database. Here's my boring youtube video on how to set this up, if you really have to know...

Wednesday, March 8, 2017

PL-259 Assembly Instructions

Conquering the PL-259
Walt Stinson,W0CP

New year's resolutions for hams.... Among the ones I've heard recently is "l will always solder the braid to the PL-259." That got me to thinking about what a hassle it is working with coax and PL-259's (not to mention hardline and N-connectors!).
Well, many years ago after consulting with Mr. Murphy, I made that same resolution. I faithfully followed the instructions for assembly of connectors in the Handbook. I remember using the tip of a nail to unravel the braid and trimming it with scissors.
Two moods would fall over me after a session of soldering 259's: Self righteousness, for I was truly entering the ranks of the deserving; and klutziness, because about half the time l would have to cut of the end I was working on and start all over again. Sometimes, I'd forget to slip on the fitting cover. Other times  I'd have an intermittant after a couple of years.
Finally, after years of trial and error. I devised a fast and foolproof method of assembling the little buggers. If you follow my prescription, I assure you that you too will enter the ranks of the deserving (of course you will also need an antenna). This method is for RG-8u, but can be modified for other coax. Remember that foam style coax has a lower melting point and is trickier to work with. I recommend sticking with solid dielectric coax for this reason.

Gather up the following tools: (Buy these tools, if you don't have them!!)
Weller D550 240/325 watt soldering gun or Weller SP-120 soldering iron
1" adjustable pipe cutter (Rigid No. 104, available at hardware stores)
Tape measure with sixteenth inch scale
Razor blade style cutting tool
Triple core 60/40 solder, .047" diameter
Black felt tip pen
Household style pliers
Vise (pana vise)
This method was developed for RG-8u, but can be modified for other coax. Remember that foam style coax has a lower melting point and is trickier to work with. I recommend sticking with solid dielectric coax for this reason.
Here are the steps: (POST THIS BY YOUR WORKBENCH)
1. Using the razor, cut off 1-1/8" of insulation.
2. Put the Weller on high and tin the braid
3. Measure 13/16" from the end of the coax and mark it with the pen.
4. Using the pipe cutter, cut through tinned braid and insulation at the mark (don't cut the center conductor!
5. Twist off the braid/insulation & tin the exposed center conductor.
6. Slip on the coax fitting sleeve!!!
7. Screw the coax connector onto the coax using the pliers until the center conductor reaches the tip of the fitting.
8. Secure coax in vise. Heat a hole in the coax fitting. Apply solder through the hole, melting it into braid.
9. Apply solder through all holes. Keep fitting hot but work quickly to avoid melting coax center insulation. Cool with water when done. Don't flex while coax is hot, allow time to cool in vise before flexing.
10. Solder the tip of the fitting and check continuity.
Since I have been using this method I have not had one intermittent problem. Moreover, my coax once got caught as I was raising my motorized crank up and the cable just about tore the tri-bander off of the tower! Fortunately the coax was connected to a balun and a remote switch. The females were ripped out of both of these but my cable was unscathed. This proves another of Murphy's laws - solving one problem simply reveals another.

[This appeared in the February 1999 edition of B. A. R. C's Bark", the newsletter of the Boulder Amateur Radio Club, and has also appeared in several other newsletters around the country. Permission to reproduce with credit is granted.]

(PL-259 Assembly Instructions)