May 19, 2015

Sugru: Duct Tape meets Playdough!

Can there be something as fun and creative as Playdough and as practical as duct tape? As a ham always looking for cool new things, I think so! It's called Sugru.

It's a new material which looks and feels like Playdough in your fingers. It comes in variety of vibrant colors and can be molded into a million different shapes. But it's after you shape it that the magic begins. simply let is sit for 24 hours to "cure" and it turns into a firm, almost rigid form of rubber. It will adhere to most surfaces and is waterproof and durable.

My first experience with Sugru came after my son dropped his table computer and splintered off a small piece of rubberize plastic trim around the edge. With a pea-sized ball of Sugru, pressed into the hole where missing piece had been, his tablet was as good as new and it was almost impossible to see the repair.

I used large marble-sized ball to create a mic holder for my FT-100D. It's looks good and works well. The Sugru website has hundreds of creative ideas of how to use the interesting stuff. There are a couple of downsides.

Once you open the Sugru package, it starts curing, which means you have to use it or loose it. for that reason, they sell it in small, single-use packets (about the size of a bite-size miniature candy bar). And it's not the cheapest fix. It comes in a pack of three for $12 or eight for $22.

Intruder Alert! Who's on the band?

Wolfgang Hadel, DK2OM
If you've spent any time at all cruising through the HF bands, you've likely come across an out-of-place signal or two. Perhaps it was an voice in the middle of the 20-meter CW sub-band or music playing at the top of 15 meters. Perhaps it was a strange data signal that sounded like RTTY but just kept repeating itself over and over again. "Where is that coming from?" you thought.

If you're Wolfgang Hadel, it's just another day on the hunt. Wolf, better known as DK2OM, spends a good portion of his time listening for rogue signal in the ham bands and trying to figure out who it behind them. He co-ordinates the International Amateur Radio Union's Monitoring System in Region 1 (Europe, Africa, Middle-East and Northern Asia). Each month Wolf compiles a newsletter highlighting what he has found and it can be very interesting reading to say the least.

Each report is filled with a spreadsheet of signals heard and their possible sources. There is also some graphs which show just have much of the bands some signal cover.

Wolf often forwards information on the worst offenders to governmental authorities who in turn can file formal complaints. In one recent case, and intruding signal even interfered with emergency traffic originating out of Napal, which is recovering from the effects of a massive earthquake.

Here is a copy of the most recent monthly report.
There is shorter version with the most recent updates available here.
Visit the monitoring system's website for more information.

May 08, 2015

Fun Stuff from the ARRL's Contest Guy

I've never scored very well in a contest, but I do appreciate the ARRL's regular "Contest Update." It goes well beyond the normal list of events and where to find contest rules. In fact, Ward Silver, NØAX, goes out of his way to compile a TON of interesting tidbits of information that appeals to more than typical contester.

Here's a some of this week's update I thought was interesting:


Measuring RF power/signal strength accurately is a non-trivial undertaking. Mike N8MSA strongly recommends this Keysight (nee Agilent nee Hewlett-Packard) tutorial or this older, more detailed treatment. Both cover the complexity caused by different modulation types, bandwidths, onset rise-time and numerous other factors.

A sky full of CubeSats? There will be if Planet Labs gets enough funding to fulfill its dream of taking one full-Earth snapshot every day! (Thanks, John WV8H)

Repurposing champ, Charlie NØTT found a great method of cable control. "I use plastic guttering from the local home center for use as a wiring/cable tray. I homebrewed some brackets to attach it to the back of my desk then cut access holes I wanted with a hole saw/drill."Every time we turn around there is a new technique to do something in your own lab which previously required special machines and techniques. Here's an EE Times story about alternative ways to do your own PCB fabrication.

Brian N9ADG found a one-dollar add-on clip to fix that RJ-45 connector with the broken-off tab that allows your microphone to fall out of the rig and under the passenger seat where you can't reach it and have to pull all the way over to the shoulder to get it and then you can't merge back on to the highway and wind up late! Wait, what was I talking about?

Technical Websites of the Week - Glenn WØGJ spotted this article about disturbances in the upper atmosphere resulting from the recent earthquake in Nepal. Does this imply a mechanism for short-term propagation caused by quakes? On the Sun, nano-flares can stir things up and add heat to the corona - like it needs to be any hotter - resulting in changes in our upper atmosphere, too. Elsewhere, the Daily Mail takes the pulse of Ol' Sol with an article about two-year cycles inside the Sun driving big solar storms. Big cycles, little cycles - as long as they make sunspots, who cares?

If you're an ARRL member and would like to receive the ARRL Contest Update yourself, you can sign up here.

May 02, 2015

New Section Manager for ARRL's NTX

Nancy McCain, K5NLM
The ARRL North Texas Section has a new Section Manager. Nancy McCain, K5NLM, from Fort Worth, formally took over the position on May 1, succeeding incumbent SM Chris Brewer, N5GMJ. Brewer resigned due to increased work and family commitments.

ARRL Field Services and Radiosport Manager Dave Patton, NN1N, made the appointment in consultation with Brewer (who recommended McCain for the post) and ARRL West Gulf Division Director Dr David Woolweaver, K5RAV. Brewer, of Saginaw, has served as the North Texas Section Manager since April 30, 2013.

McCain, who is presently a North Texas Assistant Section Manager, has been active in ARES, RACES, and in Army and Navy MARS. She is a retired emergency management specialist. She will complete the current term of office as North Texas Section Manager, which runs until March 31, 2017.

Here's the full story on the ARRL's website.