Analog-to-Digital Converter Targets Wireless Applications

This from the press release for the AD9467, an analog-to-digital converter, capable of 16-bit conversions at data rates up to 250 MHz:

Norwood, MA (09/27/2010) – The industry’s fastest 16-bit ADC (analog-to-digital converter)–at 250 MSPS (mega samples per second)–was unveiled today by data converter market share leader* Analog Devices, Inc. (ADI). The AD9467 16-bit, 250 MSPS ADC operates on 35% less power at 25% higher sampling rate than any other 16-bit data converter, providing a new level of signal processing performance for test and measurement instrumentation, defense electronics, and communications applications where high resolution over a wide bandwidth is needed.

The AD9467 delivers resolution and a fast sample rate while simultaneously achieving a high SFDR (spurious-free dynamic range) of up to 100 dBFs and SNR (signal-to-noise ratio) performance of 76.4 dBFS. The device’s SFDR of 90 dBFS up to 300 MHz analog input and 60-femtosecond rms (root mean square) jitter helps lower the signal chain bill of materials component count by allowing engineers to increase system performance at higher intermediate frequencies, thereby reducing the number of signal down-conversion stages. Download data sheet or order samples and evaluation boards.

The AD9467 can be used with ADI’s AD9523/24 low-jitter clock generators and ADL5562 3.3 GHz ultra-low distortion RF/IF differential amplifier to provide a data conversion signal chain solution.

AD9467 16-bit, 250 MSPS ADC Key Features and Benefits:

  • 16-bit resolution with high signal bandwidths up to 300 MHz enables advanced signal acquisition subsystems in common radio platforms, radar systems, and spectrum analysis.
  • On-chip IF (intermediate frequency) sampling circuit and buffered analog inputs optimize the AD9467 for the highest ENOB and ease of use.
  • High dynamic range over broad signal bandwidth enables software-defined radios for use with multiple standards, such as LTE/W-CDMA, MC-GSM (class 1) and CDMA.
  • Programmable full-scale input range allows trade-off between SNR and SFDR enabling the design of more sensitive radar systems with the ability to acquire and track smaller targets with better accuracy.

The 200MHz part will cost $100 in quantity, while the 250 MHz part will cost $120.

Can anyone say “software-defined radio”??

Some Recent, Remarkable QSOs

Time to tell you about a few recent QSOs that I found remarkable:

  • AH6V. I just worked Jerry, AH6V, not more than 15 minutes ago. At first, I almost didn’t believe him when he gave his QTH as Hawaii. Then, I looked him up on QRZ.Com. Not only is he in HI, but he’s in a fairly remote part of the big island of Hawaii. He’s got quite a shack, too (see below).

    According to his QRZ.Com page, he’s 100% solar powered.
  • PU2AIL. Lia, PU2AIL is a 16-year-old YL from Brasil. Who says ham radio isn’t for girls and young people. She had a very nice fist, too. Also, her QSL card will look great in my collection of QSLs from stations whose callsigns spell words.
  • W5CUB. My QSO with Paul, W5CUB, wasn’t so remarkable, as it was just a quick contest QSO. But, not only does his callsign spell a word, but there’s a great story behind it. According to his QRZ.Com page, he was first licensed in 1978 while still in high school in Chicago. His first callsign was KA9CUB, which was perfect for a Chicago Cubs fan! Although he now lives in TX, he’s still not only a Cubs fan, but flies a Piper Cub airplane. What a perfect callsign, no?
  • HG2010P. This is a special event station celebrating Pecs, Hungary as one of the European Capitals of Culture for 2010. If you work this station and other Hungarian special event stations several times, you can qualify for a certificate.

NIST Researchers May Have Figured Out New Way to Generate Microwaves

The following is from a NIST press release…….Dan

Researchers at the National Institute of Standards and Technology (NIST) have found theoretical evidence of a new way to generate the high-frequency waves used in modern communication devices such as cell phones. Their analysis, if supported by experimental evidence, could contribute to a new generation of wireless technology that would be more secure and resistant to interference than conventional devices.

The team’s findings point toward an oscillator that would harness the spin of electrons to generate microwaves—electromagnetic waves in the frequencies used by mobile devices. Electron spin is a fundamental property, in addition to basic electrical charge, that can be used in electronic circuits. The discovery adds another potential effect to the list of spin’s capabilities.

The team’s work—a novel variation on several types of previously proposed experimental oscillators—predicts that a special type of stationary wave called a “soliton” can be created in a layer of a multilayered magnetic sandwich. Solitons are shape-preserving waves that have been seen in a variety of media. (They first were observed in a boat canal in 1834 and now are used in optical fiber communications.) Creating the soliton requires that one of the sandwich layers be magnetized perpendicular to the plane of the sandwiched layers; then an electric current is forced through a small channel in the sandwich. Once the soliton is established, the magnetic orientation oscillates at more than a billion times a second.

“That’s the frequency of microwaves,” says NIST physicist Thomas Silva. “You might use this effect to create an oscillator in cell phones that would use less energy than those in use today. And the military could use them in secure communications as well. In theory, you could change the frequency of these devices quite rapidly, making the signals very hard for enemies to intercept or jam.”

Silva adds that the oscillator is predicted to be very stable—its frequency remaining constant even with variations in current—a distinct practical advantage, as it would reduce unwanted noise in the system. It also appears to create an output signal that would be both steady and strong.

The team’s prediction also has value for fundamental research.

“All we’ve done at this point is the mathematics, but the equations predict these effects will occur in devices that we think we can realize,” Silva says, pointing out that the research was inspired by materials that already exist. “We’d like to start looking for experimental evidence that these localized excitations occur, not least because solitons in other materials are hard to generate. If they occur in these devices as our predictions indicate, we might have found a relatively easy way to explore their properties.”


M.A. Hoefer, T.J. Silva and M.W. Keller. Theory for a dissipative droplet soliton excited by a spin torque nanocontact. Physical Review B, 82, 054432 (2010), Aug. 30. 2010. DOI: 10.1103/PhysRevB.82.054432

Could Your Ham License Be a Ticket to Afghanistan?

On LinkedIn, which is kind of like Facebook for professionals, there is an amateur radio discussion group that I belong to. One of the latest posts is titled, “I have information about radio telecommunications jobs in Afghanistan and Iraq.”

The author says:

I know of three (3) different companies that are hiring in Afghanistan/Iraq. Radio Telecommunications Support, Satellite installations, and electronic circuit anaylsis. An Amateur Radio background is very much desired for all of these .

I was curious about these claims, so I Googled, “radio telecommunication jobs iraq afghanistan” and did indeed come up with several sites listing jobs in Afghanistan, including:

On the Indeed.Com site, there was a listing for “Afghanistan Radio Technician.” Here’s the job description:

This position is based in Afghanistan (Kabul International Airport or Kandahar Air Field) and requires a 12 month commitment to the contract. Personnel must be capable of performing their duties in challenging environmental and working conditions, with extreme temperature ranges and long, STANDARD working hours consisting of 12 hours a day / 7 days a week.

This post is a radio technician with special emphasis on maintaining the theatre’s ground-to-air radio system known as Air Command and Control (Air C2). Individual will perform radio maintenance within Regional Command Capitol and will deploy to Provincial Reconstruction Teams (PRTs) and Regional Command Headquarters (RCs) to conduct Air C2 and radio maintenance. Post installs, maintains, overhauls, repairs, and modifies fixed, mobile, and transportable transmitters, receivers, transceivers, and related equipment. Included are amplitude modulation, frequency modulation, single sideband, and independent sideband radio systems and equipment for point-to-point and ground-to-air communications; facsimile receivers; low frequency, high frequency, very high frequency, and ultra high frequency radio systems; radio frequency amplifiers; recorders; keying and signal devices; generation and display equipment; and base radio and pager systems.

This listing did not include the pay scale, and of course, you’d have to be able to get a security clearance. I don’t think I’ll be sending them my resume, but it might be an opportunity for some of you out there.

I Was 2 for 3 Last Saturday

Last Saturday, I went two-for-three. No, I’m not talking about my performance on the softball field, but rather what happened at the last one-day Tech class I taught.

This was a very strange class. First of all, I only managed to get five people to register for this class. That’s odd because in nearly all of them to date, between ten and twenty signed up for the class.

Someone suggested that the low turnout was due to the fact that I’d already taught everyone within driving distance that was interested. I don’t think that’s the case, since I still have nearly 60 names on my mailing list.

Another possibility is that it was a football Saturday. Ann Arbor is home to the University of Michigan, which has the largest American football stadium in the world. The “Big House,” as they call it, accommodates nearly 110, 000 fans, and the traffic gets really bad. There’s some merit to this argument, but while we didn’t have a class in September last year, the one that we ran in September 2008 had 13 students (12 passed).

Whatever the reason, only five people pre-registered. One pulled out a few days before the class, and one didn’t show up , so there were only three in the class.

None of them, as it turns out, did any pre-study. That wasn’t a problem for one of the students, who works as an electronics technician. He only missed two questions on the test.

It was more problematic for the other two, but one of them still managed to pass the test. She scored 29/35. The third student missed by three questions, scoring only 23/35.

This class was also notable in that it was the first time that I got to be a Volunteer Examiner. The three of us administering the test were Mark, W8FSA; Jim, K8ELR; and yours truly. That was an interesting experience, but it’s too bad that we had to tell our third examinee that he failed the test.

Book Excerpt: Oscillators

Robert Lacoste writes The Darker Side column in Circuit Cellular, and now he has published a book, Robert Lacoste’s The Darker Side: Practical Applications for Electronic Design Concepts from Circuit Cellar. Topics covered span digital signal design to avoiding interference. EETimes’ RF Designline has published an excerpt from Chapter 4, which covers oscillators. There are five parts:

  1. Introduction to oscillators, including piezoelectricity and how a crystal works.
  2. How to adjust a crystal, depending on whether it is to be used as a parallel resonant frequency element or a series resonant element.
  3. A classic quartz-based CMOS oscillator.
  4. How to accurately determine oscillator start up time and stability.
  5. What happens at higher frequencies (overtone mode)?

New Turns-Counting Dials Released

A friend of mine forwarded this press release to me, saying, “Who knew? They are not only still making these, they are releasing new ones? I love these things, I have several unused ones in original boxes I picked up at a show!”

For Immediate Release

turns-counting dialRB/RBM Series precision turns counting dial ideal for industrial automation, instrumentation…

BI Technologies Develops Analog Turns Counting Dial with Enhanced Accuracy, Improved Locking Mechanism

Fullerton, CA, September 20, 2010:  Providing instrumentation and test equipment design engineers with an economical device for precision rotary indication, TT electronics BI Technologies has developed an enhanced design for its analog turns counting dials.  Designated the Model RB/RBM Series, the 1 – 13/16″ diameter turns counting dial has the capability to count up to 15 turns, and features superior turning tightness with an improved locking mechanism to meet the requirements for a wide range of industrial automation and instrumentation applications. Each dial is individually packaged to prevent damage during shipment.

According to Richard Hsieh, Marketing Director for BI Technologies Electronic Components Division, the redesigned turns counting dials provide customers with improved performance as well as shorter lead times.  “With new tooling and an improved assembly process, our design engineers were able to add these product enhancements and still deliver within four weeks at competitive pricing,” he explained.

Turns counting dials are ideal for a wide range of panel control applications, including instrumentation, bench-top power supplies, medical electronics and industrial automation equipment.

The 1 – 13/16″ outer diameter Model RB/RBM Series turns counting dials feature a maximum counting capacity of 15 turns, with a positive action locking mechanism and a satin chrome housing.  Shaft diameter is ¼” or 6mm with a bushing diameter of 3/8″.  Operating temperature range is -55°C to +71°C.

For additional information, please access the Web site at www.bitechnologies.com or email the TT electronics North America Sales Office at sales@ttelectronics-na.com. To access the data sheet and other product information for BI Technologies’ complete line of turns counting dials, please visit: http://www.bitechnologies.com/products/turns_counting.htm.

One of the Dumbest Things I’ve Ever Done in Ham Radio

Mark, W8MP, and I often argue about what’s dumber—his county hunting or my collecting QSL cards from stations whose call signs spell words. It’s one of those arguments that will never be won. When you get right down to it, they’re both pretty dumb.

Well, Wednesday morning, I got a call from my friend, Mark, W8MP. He asked, “Hey, want to do something really dumb tonight?” When I asked what he had in mind, he replied, “Well, one of my county hunter friends, Tim, W8JJ (he’s the guy looking nervous in the black cap below), claims to have confirmed all 3,077 counties. He needs at least two General Class (or higher) hams to check his QSL cards and sign off on his application for the USA-CA award sponsored by CQ magazine. I guarantee that this will be one of the dumbest things that you ever do in ham radio. I also guarantee that it will be a lot of fun.”

Checking Tim's Cards

Tim, W8JJ (left) sweats bullets as Clark, N8CBW (middle), points out a possible problem to me (right).

With a recommendation like that, how could I refuse? Mark said that he’d also invited Clark, N8CBW, another nut, errrrrr I mean county hunter, and that he was going to prepare dinner for us.

After a fine salmon dinner with some very chewy noodles (that Mark claims his son, KD8EEH insisted that he make), we cleared the table, and Tim got out his box of cards. Mark then explained how we should proceed. I was kind of curious about this, as it’s clearly impossible to check all 3,077 QSOs in a single evening.

Basically, what the two checkers are supposed to do is to check random contacts until they are satisfied that the applicant does indeed have a QSL from all 3,077 counties. To select the contacts, you might choose counties where you lived, or counties that you have visited. I hit on the idea of having Tim produced the confirmations of all 16 counties in Massachusetts. Clark, who is more familiar with which counties are the most difficult to confirm, asked Tim to produce cards from some rare counties in Colorado and Hawaii.

Above all, though, the idea is to give the applicant as much grief as possible during the process.

Mark came up with the idea of calling several county hunters that he had phone numbers for and asking them to verify in their logs some of the QSOs that Tim was claiming. He first phoned Jim, N9JF, and we asked him about a 44 report that he’d given Tim seven years ago. He wasn’t near his logbook, but he said that he did remember that contact and even rattled off the county (Wahkiakum, WA)!

Next, Mark phoned Guff, KS5A, who confirmed a contact, but was off by almost seven minutes. A long discussion ensued regarding the details of how a mobile logs contacts while out driving. In the end, we accepted the seven-minute discrepancy.

Finally, Mark phoned Larry, W0QE, to confirm a few of the MRCs that Tim had from him. (MRCs are records of multiple contacts. Using them instead of QSL cards makes the process of managing all these QSLs a lot easier.) Mark joked that it looked like one of the MRCs had a forged signature. Larry replied that all of his MRCs are stamped.

“Aha,” Clark exclaimed, “this MRC doesn’t have a stamp!”

I don’t know what was going through Tim’s mind at this point, but it probably wasn’t good. Larry then explained that he probably sent out that MRC before he got the stamp. When we confirmed those dates, I think Tim breathed a little easier.

In the end, Clark and I signed off on Tim’s application. And, even though Mark and I joke about how dumb this activity is, it’s really only a joke. In my mind, it’s quite an achievement. It takes a lot of persistence, too. It took Tim nearly ten years to do it.

Another cool thing about the county hunting sub-culture is the camaraderie amongst the county hunters. It’s the nature of the beast that you’ll be contacting many of them multiple times, and it’s inevitable that you’ll make friends with many of them.

As we were leaving, Tim said, “My wife asked me the other day if I could get now get rid of all my radios since I’ve talked to everybody.” She obviously doesn’t understand this ham radio sub-culture. Tim’s only just begun.

Book Excerpt Covers Antenna Fundamentals

EETimes has posted chapters 3 and 4 from the book Antennas: Fundamentals, Design, Measurement (Third Edition). There is a little more math than ham radio operators are generally used to, but the material is useful and interesting, if you can plow through it. Here is the available material:

Chapter 3: Antenna Parameters

  • Sections 3.1 Antenna Structures; and 3.2 Radiation Pattern.
  • Sections 3.3 Directivity and Gain; 3.4 Effective Area and Friis Transmission Equation; 3.5 Beamwidth; 3.6 Minor Lobe; and 3.7 Radiation Resistance and Efficiency.
  • Sections 3.8 Input Impedance; 3.9 Bandwidth; 3.10 Polarization; 3.11 Interdependencies of Gain, Beamwidths, and Aperture Dimensions; and References, Problems and Exercises.

Chapter 4:Basic Radiators and Feed Methods

  • Section 4.1 Short Dipoles.
  • Sections 4.2 Current and Voltage in Longer Antennas; 4.3 The Half-Wave Dipole; and 4.4 Long-Wire Antennas.
  • Sections 4.5 Loop Antennas; 4.6 Helical Antennas; and 4.7 Horn Radiators.
  • Sections 4.8 Slot Radiators; 4.9 Patch or Microstrip Antennas; 4.10 Surface-Wave and Leaky-Wave Antennas; 4.11 Basic Feed Methods; and References, Problems and Exercises.

Are Wouxoun Radios Illegal?

IC-2ATOn our ham radio club’s mailing list, a new Tech innocently asked what kind of HT he should buy. Since he mentioned that he was going to an upcoming hamfest, he asked about used equipment, and several folks suggested that he look for an ICOM IC-2AT (see right), noting that they were ruggedly built and that many were still in service. They didn’t really not that tuning them involved flipping thumbwheel switches and that to get PL tones you have to purchase a $40 board that you have to mickey-mouse into the radio, but hey, they are built like the proverbial brick outhouse.

Wouxun KG-UVD1Some guys suggested buying one of the new Chinese HTs (see right) now being sold here. They noted that for just a little more than $100, you not only get a dual-band radio, but a boatload of accessories as well.

At this point, Jeff, W8SGZ, our self-proclaimed club curmudgeon wrote:

I’ve been doing a little research.

The US “dealer” is Ed Griffin W4KMA, owner of KMA Antennas in N. Carolina (www.wouxon.us). So at least there is a US presence. The only thing that  concerns me is one little specification : spurious emission is listed as <30dB.

Part 97 says ” For a transmitter having a mean power of 25 W or less, the mean power of any spurious emission supplied to the antenna transmission line must not exceed 25 uW and must be at least 40 dB below the mean power of the fundamental emission, but need not be reduced below the power of 10 uW.” The question is, is their 30dB enough to get down to 10 uW? With only 5 W to start with, maybe it is.

The particular model in question, KG-UVD1P, is FCC “certificated” (I love that word, it’s so nonsensical) under Part 90, so it should be at least of a certain quality level. And at half the price of anything comparable from the Big 3 (or 4 if you count Alinco), it doesn’t sound bad.

Now, according to my calculations, -30 dB, only gets you down to 5 mW. To get down to 10 uW, spurious emissions would have to be -57 dB. When I replied with that information, Jeff said:

This little radio is causing me a lot more work than I like, but once I get my teeth into an investigation, I can’t seem to let it go.

Although the sales literature (what there is of it) states 30dB for spurious emissions, the User Manual states 60 dB. From what I can make out from the test reports submitted to the FCC, the actual attenuation is in the mid 20s (depending on frequency).

And most bizarre of all is this except from a letter from Wouxon to the FCC:

We would like to have the 136-174 MHz frequency range appear on the face of the FCC Grant of Certification for our Part 90 Certification. This frequency range contains frequencies regarded as usual & customary by the United States Federal Government and its various departments, user organizations and the military.

  1. The applicant plans to ensure that USA users, other than those specifically identified in this letter, not operate within bands which are not allowed by the Part 90, as controlled by the users’ FCC station license.
  2. This devise will not be marketed to USA users, other than those identified in the letter, namely the US Government and its various departments & military, for operation in frequency range out of Part 90.
  3. The applicant acknowledges that it is a violation of FCC rules if the device operates on unauthorized frequencies

Is it just me, or does all this sound like W4KMA is in violation of FCC regulations by selling these to US hams? And are US hams who buy and use them in violation as well?

There has to be a loophole somewhere that I am missing. I mean hams are continually retuning commercial (ie Part 90) equipment to use on amateur frequencies. Why would this be any different? The applicant acknowledges that it is a violation of FCC rules if the device operates on unauthorized frequencies.

So, what do you think? It sounds to me as though the Wouxoun radios don’t meet spec and should not be allowed to be sold in the U.S.