Monthly Archives: October 2014

In the News: Two ham radio satellite payloads destroyed in Antares launch explosion

The ARRL reports that two Amateur Radio payloads were destroyed in the October 28 explosion of the Antares 130 rocket:

The RACE  and GOMX-2 CubeSats were among more than 2 dozen satellites lost after an unmanned Orbital Space Sciences (OSC) Antares 130 vehicle exploded spectacularly shortly after launch at 2222 UTC on Tuesday, October 28, from the Mid-Atlantic Regional Spaceport on Wallops Island on Virginia’s Eastern Shore. Both satellite packages carried Amateur Radio payloads. The Antares is a new medium-class launch vehicle developed by OSC. The rocket exploded about 6 seconds after launch, sending a huge ball of fire hurtling toward the ground, which set a massive fire at the NASA launch site.


Read more

Quick Tips: Desoldering SMD Components

I admit it. I cruise Instructables.  And once in a while I find something worth learning about.  Last night, for some reason I clicked on “Change led color on the Logitech G502” by “markor1.”  I do not own a Logitech G502 mouse, nor will I probably ever own a Logitech G502 mouse, and if I did I probably wouldn’t want to bother changing the LED color.

But I saw this picture and I thought it was a good solution to desolder a tiny surface-mount component:

Desoldering an SMT component using a soldering iron and a copper wire (picture by “markor1” on Instructables)

It’s an elegant solution if you only need to do this a few times.

(Published from DFW, Texas)

Ham Radio History: K3DSM, Roller rinks, and the Autopatch.

I found this website many years ago by accident when I was doing some research about the old AT&T Long Lines microwave system (My friend owns an old Long Lines concrete tower in Valparaiso, Indiana).  This is the story of Gene Mitchell K3DSM and the trouble he got into with the autopatch on his amateur repeater back in the 1960s.  It’s a good story that unfortunately ends with the loss of his job from AT&T Long Lines because of his “illicit” mobile telephone connection.

Hybrid phone patches were readily available because of this, so this was used to connect the repeater to the phone line. A mechanical phone lift was used to take the phone on and off hook. Soon after the project was working, I found some touchtone equipment at Greybar Electronics and changed over to a touchtone system.

From my house in Merion, I used the tone pulse system while refining the repeater system. The radio range was not great in Merion, but I was able to develop the system and refine it. I moved to Devon in 1967 where I had an excellent high location and converted to UHF (446 & 449 Mhz)

I had a range of 30 to 40 miles and sometimes more from there and the system was impressive. I even bought a used Motorola handie talkie and mounted a touchtone dial to the back of it. This made a very portable wireless system that worked 10 to 20 miles from my house. I could make and answer calls from almost anywhere I went.

I even demonstrated the system to over 300 ham radio operators at a meeting at the GE Space Center in 1970 where 2 ham radio groups (Las Voyagers and Main Line VHF Association) merged to form a larger group (the Philadelphia Area Repeater Association) to build their own autopatch system for all to use on the 2 meter ham band.

What I didn’t mention so far, is that in 1965, I started working for AT&T Long Lines after I graduated from Valpo Tech. Mention of the system at work drew lots of questions and skepticism. The system was simply not understood. Remember now, that connecting anything to your phone line during this period of time was considered taboo. I even went so far as to pay for what was called a coupler from Bell Telephone to try to stay on the up and up.

Everything was great for years until one day, my mobile phone rang while I was waiting for a roller rink to open. As I answered the call, the guy in the car next to me became curious and started asking questions. I explained what I had and how it worked. He then told me what he had. He said he had a device that could call anywhere in the world and that the calls would be free of charge. I listened carefully. The next day, I told my supervisor at work. I also told a ham friend who worked in the district office at AT&T. Both told me it was not possible for him to have such a device or he would be caught.

(Gene Mitchell, K3DSM,


(published from DFW, Texas)

Hams in Space: ARISS taking applications for kids to talk to the International Space Station in 2015

Want to really wow some kids in your school?  ARISS (Amateur Radio on the International Space Station) is taking applications for school-to-ISS QSOs in 2015.  From the ARISS News Page:

U.S. Partners Now Accepting Proposals for Contacts in 2015
The ARISS U.S. partners have opened a window seeking formal and informal education institutions and organizations in the U.S., individually or working together, to host an Amateur Radio contact with a crew member on board the ISS during 2015. The proposal window is October 17 – December 15, 2014. Read the announcement at:

To maximize these radio contact opportunities, ARISS is looking for organizations that will draw large numbers of participants and integrate the contact into a well-developed education plan.

More details on expectations, audience, proposal guidelines and proposal form, and dates and times of Information Sessions are available at  Please direct any questions about hosting a contact in the


Published from DFW, Texas

Crosstown Traffic: KB6NU Blog – Are knobs and buttons on the way out?

My friend Dan KB6NU has an interesting post on his blog about the evolving HMI (human-machine interface) between man (or woman) and radio:

In a recent column on EETimes, an old colleague of mine, Martin Rowe, says, “Knobs and buttons are slowly on their way out. Get used to it.” He’s referring to the controls on oscilloscopes, but if he were a ham, he might just as well be talking about amateur radio transceivers, too.

We already see this happening in amateur radio. FlexRadio, and a couple of other companies, already make transceivers with no front panel controls. You must use them in conjunction with a computer to use them.

KB6NU Blog: Are knobs and buttons toast?

Electronics News: FTDI admits to destroying counterfeit consumer equipment, Ars Technica and Shashdot report Microsoft removes driver update.

Ars Technica revised an article I referenced yesterday to indicate that FTDI removed a few drivers from the latest Windows update:

Update: Microsoft has given us a statement:

Yesterday FTDI removed two driver versions from Windows Update. Our engineering team is engaging with FTDI to prevent these problems with their future driver updates via Windows Update.

A post on Slashdot also references this:

Last night, FTDI, a Scottish manufacturer of USB-to-serial ICs, posted a response to the ongoing debacle over its allegedly intentional bricking of competitors’ chips. In their statement, FTDI CEO Fred Dart said, “The recently release driver release has now been removed from Windows Update so that on-the-fly updating cannot occur. The driver is in the process of being updated and will be released next week. This will still uphold our stance against devices that are not genuine, but do so in a non-invasive way that means that there is no risk of end user’s hardware being directly affected.” This may have resulted from a discussion with Microsoft engineers about the implications of distributing potentially malicious driver software.

I can’t find this in any “official” news reports yet.

Read more

Crosstown Traffic: Sparkfun comments on fake FTDI chips, more info comes out

As I predicted yesterday, Sparkfun has now commented on the counterfeit FTDI problem.  I had no doubt that their boards, like Adafruit’s, used genuine components… but you never know what can slip into the distribution stream from others:

As soon as we heard about it (from Twitter, of course), we immediately began assessing our product line for products which might be of concern. At the moment, we have about 30 individual products using the FT232 chip. We immediately crossed most of them off the list; our in-house assemblies are all produced using chips from reputable suppliers (like Mouser, Digikey, Future, etc.).


We have less visibility into assemblies that come pre-made to us, however, so we immediately set about testing them for vulnerability to this change. Testing is still ongoing, but our preliminary tests show that current stock is not affected. We already had the discussion with suppliers in the past regarding counterfeit chips (you may recall that we had a brush with this issue in the past), so we’re quite confident in the product we’re currently selling.

Read more

Projects: Software-Defined Radio with the RTL-SDR USB Stick

The RTL2832 and antenna

The RTL2832 and antenna

Yesterday I received my latest order from Adafruit — the RTL2832 Software Defined Radio USB Stick.  This nifty little device is sold in Europe as a digital TV receiver (DVB-T) for your computer.  While not compatible with the digital TV broadcasts in the US, with some additional free software, this little guy will tune into radio signals from about 24MHz to 1850MHz.  The “software” in Software-Defined Radio refers to the fact that an application external to the receiver hardware decodes the signal however you want — AM, FM (narrow or wide), single sideband, CW, etc.  The most popular Windows application (and yes, there are Linux programs available as well – the Raspberry Pi is a popular mate for this unit) for the RTL2832 is “SDR-Sharp.”  There are some more advanced applications available that will follow trunking systems and decode some digitial systems such as DMR, D-STAR, etc.  I haven’t downloaded any of these (yet).

Read more

Crosstown Traffic: Hackaday and Adafruit Report Latest Windows Update Kills Fake FTDI Chips

This could be bad.  Apparently there are lots of counterfeit FTDI232 chips out there–these are the chips that convert your USB to RS-232 serial or TTL serial.

The folks over at Hackaday and Adafruit are reporting that the latest Windows update includes a driver that nukes fake FTDI chips.  It doesn’t just keep Windows from using them.  It bricks them, rendering them unusable.  Ever.

I have a few USB to serial devices, both board level and consumer devices.  Most of them came from reputable sources (Modern Device, Arduino, Picaxe, Tripp-Lite, etc) but I have a few Chinese imports from eBay that I expect to fail the next time I plug them in.  Adafruit reports that it

… requires it suppliers to only use genuine FTDI chips. However, no matter what it’s always possible counterfeit chips could be used when you purchase products from anyone, anywhere. We’re double and triple checking all our products and suppliers as an added precaution.

I’m assuming SparkFun will also issue a note addressing their products as well.

(as an aside, the Tripp-Lite Keyspan USB Adapter is the best USB-Serial adapter I have ever encountered.  It has worked on industrial Allen-Bradley equipment, my mobile Kenwood radio, and everything else I have plugged it into.  If you’re sick of the USB-Serial adapters that only sometimes work, shell out a few more dollars and buy one of these.)


(published from DFW, Texas)

Interesting Ideas: The “Passive Repeater”

While futzing around the Internet yesterday, I came across an entry from “Joe’s Hobby Electronics” blog.  He had a problem with getting a cell phone signal in his home.  According to Joe, his “…village is in a bit of a dip and the population density just isn’t really high enough to warrant better coverage.”  According to his post, it is illegal to use cell phone repeaters in the UK (and while doing followup research, apparently most if not all of these repeaters are illegal in the US).

In an attempt to legally overcome his signal issue, Joe is in the process of setting up a “passive repeater” (he calls it a “Waveguide” but that term means something different in the US).  The theory is simple — you put up a directional antenna aimed at the cell tower and another omnidirectional antenna in your home.  Both antennas need to be tuned as close as possible to the target frequency and connected by the shortest possible length of the best possible feedline that you can get.  Antenna tuning and quality feedline is critical because this system is entirely passive — there are no amplifiers or powered components in the system at all.  Here’s how it works:
Read more

1 2