27 March 2023


Over the past several years I've accumulated a number of tablet computers. A few I've bought out of pocket (mostly iPads for family members), some have flowed my way for evaluation by my employer, some have been given to me (usually older units that still had a bit of life left in them), and I've even been known to buy 'junkers' on eBay just to play around with. I've developed a good base of experience with tablets, and find them an interesting segment in the personal computing world. 

Most folks under 40 think that the tablet format was born when Steve Jobs announced the iPad back in 2010, but the concept of a computer tablet predates the iPad by at least a decade. I won't attempt to lay out the history of tablet computers - there's a very good Wikipedia page on the topic

Apple's big achievement was to refine the concept of a touch-capable tablet into something that was not just commercially viable, but redefined how individuals and businesses viewed tablet-based computing. If it hadn't been for the iPad, tablet computers would still be very 'niche-y' devices, used by geeks and techno-wonks but not by soccer moms or bank executives. Overnight - literally, overnight - Steve Jobs and Apple made it cool to be a tablet user. The rousing success of the iPad pulled the entire tablet market up with it. In less than a year of the iPad release, Samsung and Google hit the market with very capable Android-based devices that took off. 

Microsoft stumbled (badly) in the tablet operating system space for several years, first trying to convince the world that Windows CE was what everyone needed, then trying to force-fit a butchered version of Windows 7 onto small devices, then putting out Windows 8 and claiming it was engineered specifically for mobile computing. Windows 8 was the Windows Vista of its time, a rousing disaster. Many thought Microsoft would just walk away from the mobile operating system market, as they had recently done in the smartphone market. But Microsoft got real smart real fast about tablet operating systems, and under pressure from new corporate leadership (which was threatening to lop off heads), quickly followed Windows 8 with Windows 10. With Windows 10, Microsoft finally got it right. Windows 10 wasn't just a good tablet OS, it ended up being a great tablet OS. And it's Windows 10 that brings us to the real start of this discussion - the emergence of a fully capable Windows OS running on a tablet, and the application of Windows-based tablets in Amateur Radio.

Is a tablet a better Amateur Radio computing device than a laptop? To be honest, not in most cases. Market forces have made Windows-based laptops downright cheap affordable. For a few hundred bucks you can buy a quality laptop that's more than capable of running all of the Amateur Radio-related software; Fldigi, Winlink, WSJT-X, JS8CALL, Vara, VarAC, any of the logging programs. Plus, with a laptop you get a keyboard and, in most cases, a larger screen and more connection ports - USB, HDMI, etc. Heck, last year MicroCenter was selling a $70 Windows laptop that could be charged using a 12 volt battery, and reports were they worked pretty good. Ham radio operators were buying them like they buy their Krystal burgers - by the sack-full.

While Windows tablets are niche devices in Amateur Radio, they do have virtues that recommend them to the larger ham radio community. They tend to be smaller and lighter than laptops, making them easier to carry on POTA, SOTA and other outdoor operating activities. Most models offer all the processing power needed to handle the Amateur Radio applications listed above. They can be dual-use devices; use it like a tablet to watch your streaming content, add a keyboard and mouse and run it like a conventional laptop. 

Negatives? Yes. To start, you'll pay more for less. Compare laptops and tablets that share the same hardware specs, and the tablet will invariably cost more. With a tablet you need to add a keyboard and mouse. In the rush to make their products lighter and thinner, most tablet manufacturers are eliminating things like audio jack ports, full-size USB-B ports, and more. Many tablets are down to a single USB-C/Thunderbolt port. Most tablets have significantly smaller screens than laptops, and the Windows desktop can seem 'cramped'. Also, tablets tend to have batteries that just don't last all that long when running locally installed apps like Winlink, JS8Call, logging programs, etc. Most are optimized to stream content through a browser window, not run WSJT-X for hours at a time.

Pile-O-Tablets. Lower center - Surface Go 3. Left - Surface Pro 7. Upper right - Dell 7220
sitting on a DT Research Trimble T-10 (yellow case) and at the bottom, a Panasonic
Toughbook CF-19, a somewhat goofy laptop/tablet combo

At the time of this post there's a lot of interest in the Microsoft Surface line of tablets for ham radio field use. I'm a long time user of the Surface line, starting with the original Surface Go, then the Go 2 & 3 models, and the Surface Pro line, the 3, 5 & 7 versions. In fact, I'm writing this post using a Surface Pro 7 hooked up to a docking station running dual monitors. My experience is that, with the Surface tablet line, Microsoft flubs it, gets it right, then flubs it again. The original Surface Go running Windows 8 was a joke, and damned near killed off the product line. Then Microsoft got it right with the Surface Go 2, an ideal combination of size, processing power and battery life. Then they botched it (badly) with the Surface Go 3. It was a minor upgrade to the Go 2 that didn't add anything in terms of performance, but ended up cutting usable battery life by over 20% when compared to the Go 2. The minor upgrade was actually a downgrade. That's too bad, because the form factor of the Go 3 is ideal - small and light, with a great touch interface and a very good type cover. The Surface Go 3 is still for sale, and Microsoft is still telling users to stop believing their lying eyes and that the Go 3 battery lasts just as long as the Go 2 battery. But the user community figured it all out early on, and the Go 3 has developed a reputation as something of a turkey due to the ridiculously short battery life. I own a Go 3, and can confirm that useable battery life running installed apps is about 2 hours. I'm not joking when I say you can sit and watch the battery status indicator drop in real time. It's like watching the old Windows XP software installation progress meter, but in reverse.

The Microsoft Surface Pro tablets are the same mixed bag. Early models suffered from serious battery issues. Out of the box the battery life for all of the models wasn't bad, but the Pro 3 & 5 both had a reputation for eating their batteries fairly early in the life of the device. In fact, Microsoft was exchanging a lot of them under warranty because of faulty batteries. Microsoft seems to have finally gotten the battery issue put to bed with the Surface Pro 7, and I have to admit that the battery life is impressive. My Pro 7 has the i7 CPU and when new the battery would last up to 5 hours under load. After three years of almost daily use I'm starting to see some battery performance issues, but considering the age of the device and how I use it, that's perfectly acceptable. I've come to admire the Surface Pro 7 and can recommend it if you are looking for a tablet that can fully replace a laptop. My Pro 7 is provided by my employer, and when I retire at the end of this year I'll be looking for one as home desktop computer replacement.

Discussion of the Surface tablet line brings us to one of the main points of this post - batteries. Batteries are the Achilles heel of all tablets. Only with the last generation or two of tablet devices have the manufacturers finally gotten battery issues figured out. Every manufacturer, from Apple to Microsoft, put out devices that had serious battery issues. To make matters worse, most of these devices, particularly the Microsoft tablets, could not be opened up for a battery replacement, not even by the manufacturer. Imagine that - a $1,000 (or more) tablet that can't be opened for a battery replacement. Talk about hubris. 

This is why I no longer buy tablets or laptops for field use that don't have easily replaceable batteries. I'm talking about user-replaceable batteries - open up a battery compartment, pull out the old one and slide in a new one. In my experience, user replaceable batteries add at least a year to a device's useful life. It's usually battery issues that cause an otherwise perfectly good tablet to be tossed in the electronics recycling bin. 

Recently, I've started using a tablet that finally impresses me across the board - great performance and battery life, extremely rugged, lightweight, a very well thought out detachable keyboard and stand, and enough legacy ports to keep me happy. It's the Dell Latitude Rugged Extreme 7220 tablet. I was drawn to the Dell tablet based on my experience with my Dell 5414 rugged laptop. The 7220 is specifically designed to be used outdoors. In fact, the 7220 is IP65 and MIL-STD 810G rated, so it can survive drops and a pretty good rain shower. Dell has done an outstanding job with the design and execution of their rugged computers, and I think they have beaten Panasonic at their own game.

Some of the other benefits of using a tablet (from any manufacturer) specifically designed for outdoor use include

  • a sunlight readable screen
  • a wider range of connection ports
  • integrated GPS (becoming more common on tablet devices)
  • SIM card capability for use with wireless data plans - an option, but a very handy one
  • and, of course, multiple user replaceable battery options
While small compared to the overall sales of tablets, the ruggedized tablet market is still pretty big. Government agencies at all levels buy these in bulk (your tax dollars at work), and many of them end up on the used market after a few years. Some look like they've been dragged behind a HMMWV (and probably were), and some look like they were never taken out of the box. EBay has page after page of rugged tablets from a wide variety of resellers on offer. 

One last bit of advice. When you go looking for a rugged tablet, new or used, make sure you can get reasonably priced replacement batteries for it. This is an issue that works in favor of the major manufacturers like Dell and Panasonic. Batteries for their rugged tablets are available just about everywhere, and are reasonably priced. Need a battery for a 10 year old Toughbook? No problem, someone has a new production model available, and it won't cost a fortune. I say this because there are a number of really good rugged tablets made by smaller manufacturers for which batteries are either no longer available, or very expensive. A good example is the yellow framed tablet in the picture above. It's manufactured by a company called DT Research, which makes a lot of custom tablets for vertical markets. The tablet is sold by the survey equipment manufacturer, Trimble. It's a great tablet - an excellent screen, and i7 processor and lots of system memory. But replacement batteries for it run $350.00. Yes, three hundred and fifty bucks. And there are no cheap versions available on eBay or AliExpress. Great tablet on not, I'm not going to invest in a device that requires $350 replacement batteries.

That's it! If you are using a tablet for your ham radio activities I'd love to hear about your experiences. What tablet(s) are you using? How is it working out for you? Inquiring minds want to know!

W8BYH out

22 March 2023

Paper Maps

I'm a GIS (Geospatial Information Services) professional. I've been 'doing' computer-based mapping  since the late 1980s, and my conventional GIS experience goes back to my undergraduate days in the late 1970s. Today I run the largest GIS program in the US civilian airport industry, at the world's busiest airport. I also do a lot of GIS work to support Amateur Radio activities at the state and regional level. If you've ever seen the ARES Southeastern US Situational Awareness Map, that's mine. I use web-based maps every day, build them for customers almost every week, and I work on very complex projects that embed GIS mapping technologies into other applications. I understand the GIS technology inside and out, I'm a huge promoter of the uses and benefits of GIS, and I've built a pretty good career on it.

And I still use paper maps.

Computer-based GIS is a very vulnerable technology. Everything comes to the end user via a web browser (with a few exceptions, but they are minor). This implies internet access, power, and a working computer. When any one of those three goes away, your access to digital GIS maps goes away. Consider:
  • Hurricane Maria - Puerto Rico
  • Japan - the 2011 earthquake and subsequent tsunami
  • Turkey - the February 6th earthquake along the Turkey - Syria border
  • California - the 2019 Kincade wildfire
In each of these events, modern web mapping services were available. But power and internet outages meant these mapping services could not be accessed for days or weeks within the affected areas. Even after power and internet were restored, there were still limitations on available bandwidth. This meant limited access to web maps, even for first responders using prioritized networks. 

Closer to home, my radio club has long supported the National Weather Service forecast office in Peachtree City, GA. Our job is to contact storm spotters via Amateur Radio. Many of these spotters live in remote parts of the state that have very vulnerable infrastructure. Power and internet outages are a feature of life in rural Georgia, and services will be out for hours or days. Prior to 2019 that wasn't too big of an issue. Most spotters who were Amateur Radio operators had battery back-up for their radios and could keep operating and submitting reports. At the NWS forecast office, state-level street atlases could be seen at all the forecaster workstations, and we always had one at the spotter station. They were all the same, the DeLorme Atlas & Gazetteer for Georgia. We also encouraged storm spotters to use the DeLorme atlas. This commonality was important. DeLorme overprints a grid on each map - a simple x, y grid that makes it easy to identify location. For example, a spotter might call in and say, "I'm at the intersection of Pine Road and Sandy Street in Eastman." We'd ask him if he had a DeLorme atlas and if he did, to give us his location by page number and grid box. That way we could easily and quickly identify his location. This only works if, a. everyone has an atlas and, b. everyone has the same atlas.

This post isn't an advertisement for DeLorme product. It's just what Georgia Skywarn adopted years ago. Other atlas products put out by companies like National Geographic or Benchmark can serve just as well. The important point is that everyone needs to be using the same atlas.

Around 2019, and with the arrival of COVID, how we support the forecast office changed. A lot more support is remote, and everyone started using NWS Chat to post spotter reports. But NWS Chat suffers from the same vulnerability web maps do - no power or internet, no NWS Chat. We can still communicate and take reports via Amateur Radio, but without a map it's difficult to visualize where the incidents occurred and start connecting the dots. 

When the internet isn't available (for any reason) it's back to paper maps. While paper maps and atlases are a back-up to on-line web maps, they are a critical back-up. In ARES and Skywarn we should be standardizing the paper-based map tools we use as back-ups, and focusing some training activities around the assumption that all power and internet is out, and paper maps are all we have available. Remember, only one end of the radio conversation needs to be without power or internet for both operators to have to revert to paper maps.

So take it from this GIS guy - at some point Mother Nature will have her way, and either you or the spotter at the other end of the radio link (or both) will be operating in the dark, with a flashlight, using a car battery to power your rig. You're going to be glad to have that paper map.

W8BYH out

12 March 2023

Backyard NVIS

Yesterday between yard care sessions (I'm refusing to surrender my Bermuda sod to the weeds), errands and other duties, I found the time to give an initial try to something I've wanted to test for a while now - using a lightweight off-center fed dipole (OCFD) in NVIS mode with either my Icom IC-705.

A few months back I bought a lightweight 10 - 80 meters OCFD from Tim Ortiz, N9SAB (check his eBay store here). This antenna was getting pretty good reviews, and for a time Chameleon was selling them (heck of an endorsement right there). 

Once I got it I began to think, would there be a way to deploy this in my yard, without having to sling lines in trees? Then I spied a small pile of fiberglass electric fence stakes I'd used on another project and thought, "... hmmm, why not give an NVIS seup a try?" So, off to Tractor Supply for more electric fence stakes. In ham radio one can never have too many electric fence stakes. When I laid out the antenna I realized that it was too long to fit in my back yard! I would have to lay about 15' of the antenna over the chain link fence at the back of my property. That wasn't going to work. I ended up dog-legging the last 20 feet or so of the antenna. I figured that would make for an interesting radiation pattern!

Aerial shot of my house showing the dog-leg layout. The blue dot is the feedpoint

Setup was quick and simple - just place the fence stakes at regular intervals and drape the antenna wire over them. The feedpoint was set close enough to my deck that I could reach it with 20' of RG-58.

One end of the OCFD. If you look close you can
see the rest of the stakes stretching out in the distance

The far end of the OCFD, at the end of the 'dog-leg'.
That's my Davis weather station in the background,
which you can monitor on APRS.fi
(just search for W8BYH)

Here's the feedpoint of the OCFD, with a small common mode choke

The feedline is lashed to a deck rail using a large
Nite-Ize gear tie - very handy

In the end I had the antenna set up only 3' off the ground, right up against a stone retaining wall and dog-legged at the far end. Would it tune? Would it get a signal out? Will Ross and Rachel ever get married? (Oops, sorry - the XYL's been binge-watching Friends and that stupid show's just stuck in my brain.)

I hooked up my IC-705 I did some SWR testing without the tuner. I was surprised and delighted to find that this antenna is well below 1.5:1 on 10, 20 & 40 meters, and just a bit less than 3:1 on 80 meters. In fact, on 40 & 20 the SWR was almost dead flat. 

Next it was a trial with Winlink on 40 meters using just the IC-705 factory battery (meaning only 5 watts or less output). The Winlink propagation prediction window said it was a lousy time for 40 meters, at best a 60% chance of hitting any station. But what's life without challenges, eh?

IC-705 running 'barefoot'. I'm guessing my ERP was probably
just 2 - 3 watts

OK, I'll admit it, connecting to a gateway on 40 meters was tough. but I did manage to get to the AJ4GU gateway (about 50 km) and W4MRB (200 km). Because of time constraints I did not get to hook up the tuner and try for an 80 meter gateway. I'll try that another day soon.

What are the take-aways from this? First, that NVIS does work, and works on low power digital modes. The second is that with a handful of fiberglass electric fence stakes I can set up an effective NVIS antenna just about anywhere. And third, this is just a whole lot of fun!

W8BYH out

04 March 2023

Mother Nature Will Have Her Way

Japan is a highly developed, wealthy, highly cultured and thoroughly modern nation. Japan is also no stranger to earthquakes and tsunamis. In fact, Japan leads the world in earthquake-resistant construction techniques, earthquake prediction, and advanced warning systems, and the entire Japanese population is highly tuned to the threats of both earthquakes and tsunamis. They live with earthquakes as part of their daily lives, they plan for them, run endless drills to respond to them, and have built their infrastructure to be earthquake resilient.

And yet... March 11th, 2011. A magnitude 9.1 earthquake 70 miles east of the Oshika Peninsula, deep in the Pacific Ocean, instantly overwhelmed Japan's ability to respond. Now known as the Great Tohoku Earthquake, it was the most violent ever recorded in Japan, and the resulting tsunami crested at over 130 feet in some areas. To make matters worse, a 50' high wall of water hit the Fukushima Nuclear Power Plant, knocking cooling systems off-line and ultimately causing a melt-down in three of its four reactor cores. Japan is still dealing with the mess today.

I recently stumbled on this video put together in 2021 by the Japanese public broadcaster NHK. It is 49 minutes of mostly raw, unedited film footage of the disaster, and the few days following. It's clear the Japanese authorities, despite their best efforts, were immediately overwhelmed. Nothing could have prepared them for a disaster of this scope and scale. In the video you'll witness food & water shortages, shelter shortages, fuel shortages, medical shortages, even shortages of blankets and warm clothing (at one point workers at a shelter was pulling curtains off the windows to use as blankets), 

I don't care how good FEMA or your state and local EMAs are, at some point nature will rear her ugly head and we'll be dealing with a situation that quickly spins out of control. The Japanese learned the hard lesson: Mother Nature will have her way. This is San Francisco (1906 earthquake), New Orleans (Hurricane Katrina), Puerto Rico (Hurricane Maria). Each time the authorities were confident they could handle it. Each time, Mother Nature made fools of them.

What's the point in all of this? Preparedness. Not just communications, but preparedness and security in all its aspects. Food & water security, shelter security, energy & power security, financial security, physical and personal security. Watch the video. Absorb the lessons. 

W8BYH out