From my inbox: 100 years of ham radio, spectrum analysis, mesh networks

Celebrating 100 years of ham radioThis month marks the centennial of the American Radio Relay League, the largest ham radio association in the United States. That means it will be a special year for the hundreds who converge annually on W1AW, a small station known as “the mecca of ham radio” in Newington, Conn., to broadcast radio signals across the globe.

Spectrum Analysis Basics - Application Note 150Spectrum Analysis Basics – A Resource Toolkit. Learn about the fundamentals with Agilent’s most popular and recently updated application note, Spectrum Analysis Basics – Application Note 150, which is now paired with a toolkit of app notes, demo videos, web/mobile apps, and related material.

When the Internet Dies, Meet the Meshnet That Survives. The art and technology nonprofit center Eyebeam recently staged a small-scale scenario that mimicked the outage that affected New York after Superstorm Sandy hit in 2012. As part of the drill in Manhattan, a group of New Yorkers scrambled to set up a local network and get vital information as the situation unfolded.

From my Twitter feed: digital TV, vintage computers, 10 GHz

ke9v's avatarJeff Davis @ke9v
DATV-Express digital-ATV project flip.it/GUG5j #hamradio

 

Apple1computer's avatarDavid Larsen KK4WW @Apple1computer
RT @computerhobby: #Vintage #Computers Peek inside the Bugbook Historical Microcomputer Museum warehouse ow.ly/vAczx #Floyd_VA

I used to work for Jon Titus, one of the founders and owners of the company that published the Bugbooks. Jon’s a ham, too. His call is KZ1G.

 

arrl's avatar

ARRL @arrl
ARRL Asks FCC to Dismiss “Fatally Flawed” Petition for Rule Making Affecting 10 GHz: The ARRL has told the FCC… tinyurl.com/n3948yc

2014 Tech study guide: station setup

There were two question changes in this section. Question T4A02 was changed from a question about headphones to a question about using computers in the shack. Question T4A05 was changed from a question about band-reject filters to one about using an SWR meter. I’ve added that question to the appropriate section…Dan

When setting up an amateur radio station, choosing the radio itself is the most important consideration, but you must also choose a wide range of accessories, such as power supplies and microphones. In addition, how you set up the station is important for it to operate efficiently.

One accessory that you’ll definitely need is a power supply to provide the DC voltage and current that your radio needs. A good reason to use a regulated power supply for communications equipment is that it prevents voltage fluctuations from reaching sensitive circuits. (T4A03) When choosing a supply, check the voltage and current ratings of the supply and be sure to choose one capable of supplying a high enough voltage and enough current to power your radio.

If you are going to operate with one of the voice modes, you’ll need a microphone. When considering the microphone connectors on amateur transceivers, note that some connectors include push-to-talk and voltages for powering the microphone. (T4A01)

A computer has become a very common accessory in an amateur radio “shack.” All of these choices are correct when talking about how a computer be used as part of an amateur radio station (T4A02):

  • For logging contacts and contact information
  • For sending and/or receiving CW
  • generating and decoding digital signals

If you plan to operate packet radio, you will need a computer and a terminal controller, or TNC, in addition to the radio. A terminal node controller would be connected between a transceiver and computer in a packet radio station. (T4A06) The TNC converts the ones and zeroes sent by the computer into tones sent over the air.

A more modern way to operate digital modes, such as RTTY or PSK-31, is to use a computer equipped with a sound card. When conducting digital communications using a computer, the sound card provides audio to the microphone input and converts received audio to digital form. (T4A07) The sound card may be connected directly to the radio, but it’s usually better to connect it through a device that isolates the radio from the computer. This prevents ground loops from causing the signal to be noisy.

Audio and power supply cables in a amateur radio station sometimes pick up stray RF. At minimum, this RF can cause the audio to be noisy. At worst, it can cause a radio or accessory to malfunction. To reduce RF current flowing on the shield of an audio cable (or in a power supply cable), you would use a ferrite choke. (T4A09)

Modern radio equipment is very well-designed, and harmonic radiation is rarely a problem these days. Even so, there may be times when it does become a problem, and you’ll have to take steps to attenuate the harmonics. To reduce harmonic emissions, a filter must be installed between the transmitter and the antenna. (T4A04)

Good grounding techniques can help you avoid interference problems. When grounding your equipment, you should connect the various pieces of equipment to a single point, keep leads short, and use a heavy conductor to connect to ground. Flat strap is the type of conductor that is best to use for RF grounding. (T4A08)

If you plan to install a radio in your car and operate mobile, you have a different set of challenges. One is connecting the radio to the car’s power system. Some amateurs connect their radio with a cigarette lighter plug, but this plug is not designed for high currents. Instead, a mobile transceiver’s power negative connection should be made at the battery or engine block ground strap. (T4A11) The positive connection can also be made at the battery or through an unused position of the vehicle’s fuse block.

Another challenge is noise generated by the car itself. One thing that could be happening if another operator reports a variable high-pitched whine on the audio from your mobile transmitter is that noise on the vehicle’s electrical system is being transmitted along with your speech audio. (T4A12)

The alternator is often the culprit.  The alternator is the source of a high-pitched whine that varies with engine speed in a mobile transceiver’s receive audio. (T4A10) Should this be a problem, there are filters that you can install to mitigate the alternator whine. One thing that would reduce ignition interference to a receiver is to turn on the noise blanker. (T4B05)

From my Twitter feed: lightning, HackRF, Arduino Morse

va7vm's avatarMerrick Grieder @va7vm
” So, yes, lightning could strike, but it just doesn’t strike like it used to.” theatlantic.com/technology/arc…

 

dangerousproto's avatarDangerous Prototypes @dangerousproto
DCC/TAPR video: HackRF – A Low Cost SDR Platform goo.gl/f4hkJs

 

hackaday's avatar

hackaday @hackaday
New post: Magic Morse Arduino Trainer bit.ly/LhxZ3J

Operating notes: odd behavior

Today, several odd things happened.

First of all, something odd happened with my new shack computer. I wandered down to the shack about 11:30 am, turned on the power supply, turned on the radio, and then booted up the computer. After the computer booted, I loaded the N3FJP logging program.

Right away, the computer gives me some error message about COM3, the port to which the USB CI-V cable connecting my IC-746PRO to the computer is assigned. I also note that the logging program is not recording the rig’s mode and frequency setting. I think to myself that I’ll just ignore that for now and troubleshoot that later.

I tune around a bit, and not hearing anyone, call QRL? At that point, all hell breaks loose. Windows start resizing and the mouse pointer starts jumping around the screen. It was as if the mouse, which showed no signs of RF susceptibility before this, suddenly decided to act wonky.

So, I disconnect the mouse, but I still get this odd behavior. Hmmmmmm, strange. I disconnect the audio in from the microphone jack on the odd chance that was causing the problem, but no, that wasn’t it, either.

At that point, the only other thing it could be is the USB CI-V cable. I unplugged that and the wonky behavior goes away. Not only that, I plug it back in, and the rig and the computer start communicating again. Really weird.

Short skip
The next odd thing to happen is that the skip was really short this morning. The first contact I made was with a ham in Wyandotte, MI, which is about 30 miles directly east of me. The second contact I made was with a ham in Grand Blanc, MI, which is about 45 miles directly north of me. I think that these contacts were both made via sky wave, as a) both stations were S9 and b) ground wave signals would have been much weaker.

On the U-M net tonight, someone mentioned that such odd behavior could have been the result of the high solar flux index. This weekend, the SFI is as high as it’s been in a long time.

Odd transmitter behavior
Another odd thing this morning was the behavior of the Wyandotte ham’s transmitter. Whenever he would begin a transmission, the signal was very weak. As the transmission progressed, however, the signal would get stronger until it reached a peak of S9. It was almost as if a capacitor with a really long time constant was charging up, and as the capacitor charged, the output power increased.

 

From my Twitter feed: ham radio apps, pirate radio QSLs, and more

KC8GRQ:
My “Amateur Apps” presentation was a big hit at the #hamr club meeting last night. Its available for anyone to use.http://t.co/VRd0PLIf

This looks like a good presentation. I might suggest that we give it at our club.

jilly:
Shortwave QSL Cards – Pirate & Clandestine Radio #pirateradiouploaded to flickr mostly 1990′s erahttp://t.co/X66OZx9T

SWL QSL card fun

AlanAtTek:
Woo-Hoo! 275,000 views on my little YouTube channel about ham radio, electronics and test & measurement.http://www.youtube.com/user/w2aew

Alan does great videos.

Amateur radio videos: Arduino, K6H, British humor

More ham radio YouTube videos:

Ham radio Arduino beacon. A simple ham radio morse beacon comprising a Barbones arduino, and a keyed oscillator. Sources of all info except the oscillator are in the credits and clip. You can key any simple oscillator the same way.

Working K6H Special Event Ham Radio Station On The Set Of “Last Man Standing” I haven’t yet watched this show, but I think it’s pretty cool that they were able to operate from the set.

The BBC on Ham Radio – 1950s Style. Here’s some vintage Tony Hancock and the “The Radio Ham”. To be honest, I couldn’t watch this all the way to the end, but you might find it more humorous than I did.

 

From my inbox: Morse Code, WWV, Raspberry Pi

Here are three interesting items that I found out about by reading my e-mail:

  • Original Morse Code with Phillips PunctuationMorse Code Chart, including Phillips Punctuation. At right is a chart, showing the American Morse Code with Phillips punctuation. According to the book, A treatise on telegraphy, published in 1901, “The Phillips punctuation has superseded the Morse for punctuations, and and is much more complete and systematic. Except for submarine telegraphy, the Morse code for letters and numerals and the Phillips code for punctuation are used throughout the United States and Canada.” Click on the image for a larger, more readable chart.
  • At The Tone is the first comprehensive audio survey of NIST Radio Stations WWV and WWVH: two legendary shortwave radio broadcasters whose primary purpose is the dissemination of scientifically precise time and frequency. Offered here publicly for the first time, the set represents a huge cross-section of the stations’ “life and times,” including recordings of obsolete formats, original voices and identifications, special announcements, format changes, “leap seconds,” and other aural oddities from 1955 to 2005. Produced, compiled, and edited by Myke over a 20-year period (1992-2012), At The Tone is alternately strange and mundane, monotonous and compelling, erudite and obscure. Recommended for fans of The Conet Project, The Ghost Orchid, and other radio-related ephemera.
  • Raspberry Pi 4 Ham Radio.  This mailing is for amateur radio operators using the Raspberry Pi in ham radio applications. Looks interesting, but am not sure I want to subscribe to yet another ham radio mailing list.

From my Twitter feed – 11/27/12

Here are three items that showed up in my Twitter feed yesterday:

  1. Morse Code Plays a Role in New Spielberg Movie. Producer Steven Spielberg has used Amateur Radio or Morse code in three of his last four movies: Super 8 (2011), The Adventures of Tin Tin (2011) and Lincoln(2012). Members of the Morse Telegraph Club (MTC) — an association of retired railroad and commercial telegraphers, historians, radio amateurs and others with an interest in the history and traditions of telegraphy and the telegraph industry — played an integral part in the production of Lincoln.
  2. nanoKeyer

    The nanoKeyer is powered by open-source software running on an Arduino Nano.

    nanoKeyer powered by Arduino Nano. The nanoKeyer is an Arduino Nano based CW Contest Keyer Addon. It was designed specifically for use with the K3NG Arduino keyer open-source firmware adding many features and flexibility. The nanoKeyer is suitable as a standalone keyer or for keying the radio via the USB port by using the K1EL Winkeyer protocol from a connected computer and your favoured contest logging software. By means of the K3NG firmware it can be also used as a computerless keyboard keyer by attaching a PS2 keyboard to it.

    Someone tweeted me about this after I Tweeted about building a second WKUSB keyer. I think that if I had known about this before my purchase, I would have gone for this instead of the WKUSB. It not only purports to what the WKUSB does, the software is open-source meaning that you could actually fool around with it if you liked. You can find more information at the Radio Artisan website.

  3. Digispark. Talking about tiny Arduinos, check out this Kickstarter project. It’s amazingly cool. Unfortunately, it doesn’t look as though you can get in on this first production run.

On the Internet – 11/26/12

WITCHWITCH gets a reboot. The world’s oldest digital computer was brought back to life by engineers at The National Museum of Computing in Buckinghamshire, England. The computer was first turned on in 1951 and uses 480 relays and 828 vacuum tubes called Dekatrons, which store ten discreet values. EETimes also ran a story on this computer.

First Visible LED Demoed 50 Years Ago. Since we’re doing history today, here’s a link to a Wired article marking the first demonstration of an LED that emitted visible light. The article notes, “In the February 1963 issue of Reader’s Digest, Holonyak predicted that the LED would eventually replace incandescent bulbs. Bold words from a man who worked for GE, a company founded by Thomas Edison.” We’re finally getting around to this 50 years later.

How to Listen to Real Spy Broadcasts Now. Lifehacker shows you how to dial in to numbers stations and the like. The article says, “The behavior of shortwave radio in the atmosphere makes it ideal for long range radio transmission. You can send messages on a given frequency all over the world, and most people who use shortwave radio use it to communicate with ships at sea and people in locations all over the world.”