Archive for the ‘Uncategorized’ Category
From Lightning Comes a New Icom IC-7610 (First Transmission)
Wow. What a radio!
One of the most useful (and, to me, amazing) features of this Icom IC-7610, is the IP+ function, which, when turned on, improves the Intermodulation Distortion (IMD) quality by optimizing the direct sampling system performance. This function optimizes the Analog/Digital Converter(ADC) against distortion when you receive a strong input signal. It also improves the Third-order Intercept Point (IP3) while minimizing the reduction of the receiver sensitivity.
In short: I was listening to an s-0 (i.e., no strength-meter movement) weak signal of a DX station, when right adjacent to the frequency came an s-7 signal, wiping out my ability to copy that weak signal. I turned on the IP+ and the distortion of the adjacent signal disappeared, and once again, I heard the weak signal IN THE CLEAR! WOW!
This video is a quick capture of my running the Olivia Digital Mode on HF, on the 30-Meter band. The transmissions are of a two-way Olivia digital-mode radio conversation between station K8CJM and station NW7US on 12 November 2019 (UTC date). K8CJM is located in Dayton, Ohio, and I am located in Lincoln, Nebraska. I’m running the radio at full power. The radio is rated as being able to handle 100% duty cycle at full power. The radio ran cool, no significant heating.
A few months ago, a lightning strike took out my ham radio station. The antenna was NOT connected, but I did not unplug the power supply chain and my computer from the wall. The surge came in through the power mains, and fried my uninterruptable power supply, the interfaces between my PC and radio, and fried the radio. Thankfully, all of that was covered by my homeowner’s insurance policy, less the steep deductible. My insurance covered all of the blown items, and that provided me this chance to obtain a repack version of the Icom IC-7610. I bought an extended four-year warranty.
CAUTION: Check the documentation of your transceiver/transmitter. NEVER run your radio’s power out at a level that exceeds what it can handle in reference to the duty cycle of the mode you are using. Olivia, for instance, is a 100-percent duty cycle mode. Morse code is NOT quite 100% duty cycle. Nor is SSB, a mode that operates with a duty cycle much lower than 100%. Your radio’s manual should tell you the specifications regarding the duty cycle it can handle! If you run more power than your radio can handle with the given duty cycle of the mode in use, you will blow your radio’s finals or in some other way damage the radio! Beware! I’ve warned you!
Compression and ALC!?
Some have noted that it appears that I’ve left on the Compression of the transmitted audio. However, the truth is that compression was not being used (as is proof by carefully taking note of the zero meter movement of the Compression activity). I had the radio set for 20-Meter USB operation on the Sub VFO. Compression was set for standard USB operation. Note also that the radio was transmitting USB-D1, which means the first data/soundcard input to the radio.
Also, some people complain about my use of ALC, because, in their view, ALC (automatic level control) is a no-no for data modes.
The notion that one must NEVER use ALC when transmitting digital modes is not accurate.
Multi-frequency shift keyed (MFSK) modes with low symbol rate–such as the Olivia digital modes–use a single carrier of constant amplitude, which is stepped (between 4, 8, 16 or 32 tone frequencies respectively) in a constant phase manner. As a result, no unwanted sidebands are generated, and no special amplifier (including a transmitter’s final stage) linearity requirements are necessary.
Whether the use of ALC matters or not depends on the transmitted digital mode.
For example, FSK (Frequency-Shift Keying; i.e., RTTY) is a constant-amplitude mode (frequency shift only). In such a case, the use of ALC will NOT distort the signal waveform.
PSK31 does contain amplitude shifts, as an example, therefore you don’t want any ALC action that could result in distortion of the amplitude changes in the waveform.
On the other hand, the WSJT manual says that its output is a constant-amplitude signal, meaning that good linearity is not necessary. In that case, the use of ALC will NOT distort the transmitted signal-amplitude waveform. You can use ALC or not, as you choose when you run WSJT modes, or Olivia (MFSK).
Clarification
Nowhere in this am I advocating running your audio really high, thinking that the ALC will take care of it. I am not saying that. I am saying that some ALC is not going to be an issue. You MUST not overdrive any part of the audio chain going into the transmitter!
Transmit audio out of the sound card remains at a constant amplitude, so there will be no significant change in power output if you adjust your input into the radio so that the ALC just stops moving the meter, or, you can have some ALC meter movement. You can adjust your audio to the transmitter either way.
If the transmitter filters have a significant degree of ripple in the passband then you may find that RF power output changes with the selected frequency in the waterfall when there is no ALC action. Allowing some ALC action can permit the ALC to act as an automatic gain adjustment to keep the output power level as you change frequencies.
Linear and Non-Linear
Regarding linear and non-linear operation (amplifiers, final stages): While a Class-C amplifier circuit has far higher efficiency than a linear circuit, a Class-C amplifier is not linear and is only suitable for the amplification of constant-envelope signals. Such signals include FM, FSK, MFSK, and CW (Morse code).
If Joe Taylor’s various modes (in WSJT software) are constant-envelope signals, than class-C works, right? At least, in theory.
Some Additional Cool History
The digital mode, Thor, came out of DominoEX when FEC was added. Here is an interesting history of FSQ that seems to confirm that FSQ is like MFSK, so no problem with a bit of ALC.
The following is from https://www.qsl.net/zl1bpu/MFSK/FSQweb.htm
History – Let’s review the general history of Amateur MFSK modes. The first Amateur MFSK mode developed anywhere was MFSK16, specified by Murray Greenman ZL1BPU, then first developed and coded by Nino Porcino IZ8BLY in 1999. Before MFSK16 arrived, long-distance (DX) QSOs using digital modes were very unreliable: reliant, as they were, on RTTY and later PSK31. MFSK16 changed all that, using 16 tones and strong error correction. Great for long path DX, but nobody could ever say it was easy to use, never mind slick (quick and agile)!
Over the next few years, many MFSK modes appeared, in fact too many! Most of these were aimed at improving performance on bands with QRM. Most used very strong error correction, some types a poor match for MFSK, and these were very clumsy in QSO, because of long delays.
The next major development, aimed at easy QSOs with a slick turnaround, was DominoEX, designed by Murray Greenman ZL1BPU and coded by Con Wassilieff ZL2AFP, which was released in 2009. Rather than using error correction as a brute-force approach, DominoEX was based on sound research and achieved its performance through carefully crafted modulation techniques that required no error correction. The result was a simpler, easier to tune, easily identified mode with a fast turn-around.
DominoEX is widely used and available in many software packages. A later development by Patrick F6CTE and then Dave W1HKJ added FEC to this mode (THOR) but did not add greatly to performance, and at the same time eroded the fast turn-around. The final DominoEX- related development was EXChat, a version of DominoEX designed specifically for text-message style chatting. While completely compatible with DominoEx, it operates in ‘Sentence Mode’, sending each short over when the operator presses ENTER. EXChat was developed by Con ZL2AFP and released in 2014.
Back in 2013, Con ZL2AFP developed an MFSK mode for LF and MF which used an unusual decoding method pioneered by Alberto I2PHD: a ‘syncless’ decoder, which used a voting system to decide when one tone finished and another began. The first use of this idea was in JASON (2002), which proved to be very sensitive, but very slow, partly because it was based on the ASCII alphabet. The new mode, WSQ2 (Weak Signal QSO, 2 baud) combined the syncless decoder with more tones, 33 in total, and an alphabet specially developed by Murray ZL1BPU, which could send each lower case letter (and common punctuation) in just one symbol, resulting in a very sensitive (-30 dB SNR) mode with a 5 WPM typing speed.
In the subsequent discussion in late 2014, between the developers ZL2AFP and ZL1BPU, it was realized that if the computer had enough processing power to handle it, WSQ2 could be ‘sped up’ to become a useful HF chat mode. This required a large amount of development and retuning of the software to achieve adequate speed was involved, along with much ionospheric simulator and on-air testing used to select the most appropriate parameters.
Tests proved that the idea not only worked well, but it also had marked advantages over existing HF MFSK modes, even DominoEX. As expected, the new mode was found to have superior tolerance of signal timing variation, typically caused by multi-path reception, and would also receive with no change of settings over a wide range of signaling speeds.
So this is how FSQ came about. It uses the highly efficient WSQ character alphabet, IFK+ coding, the same number of tones as WSQ (33), but runs a whole lot faster, up to 60 WPM, and uses different tone spacing. The symbol rate (signaling speed) is modest (six tones per second or less), but each individual tone transmitted carries a surprising amount of information, resulting in a high text transmission speed. And it operates in ‘Chat’ (sentence) mode, which allows the user to type as fast as possible since they type only while receiving.
The ability to send messages and commands selectively has opened a huge array of communications possibilities.
What Makes FSQ Different
Incremental Keying – FSQ uses Offset Incremental Frequency Keying (IFK+), a type of differential Multi-Frequency Shift Keying (MFSK) with properties that make it moderately drift-proof and easy to tune. IFK+ also has excellent tolerance of multi-path reception.
IFK was developed by Steve Olney VK2XV. IFK+ (with code rotation) was proposed by Murray Greenman ZL1BPU and first used in DominoEX. IFK+ prevents repeated same tones without complex coding and provides improved rejection of propagation-related inter-symbol interference. In the context of sync-less decoding, the IFK+ code rotation also prevents repeated identical tones, which could not have been detected by this method.
Efficient Alphabet – In FSQ, a relatively high typing speed at a modest baud rate comes about because the alphabet coding is very efficient. All lower case letters and the most common punctuation can be sent in just one symbol and all other characters (the total alphabet contains 104 characters) in just two symbols. (The alphabet is listed below). This is a simple example of a Varicode, where it takes less time to send the more common characters. The character rate is close to six per second (60 WPM), the same as RTTY, but at only 1/8th of the baud rate. (RTTY has only one bit of information per symbol, 7.5 symbols per character, and wastes a third of its information on synchronization, and despite this, works poorly on HF).
No Sync – Another important factor in the design of FSQ is that no synchronizing process is required to locate and decode the received characters. Lack of sync means that reception is much less influenced by propagation timing changes that affect almost all other modes since timing is quite unimportant to FSQ; it almost completely eliminates impulse noise disruption, and it also contributes to very fast acquisition of the signal (decoding reliably within one symbol of the start of reception). Fast acquisition removes the need for the addition of extra idle characters at the start of transmission, and this leads to a very slick system. Add high resistance to QRM and QRN, thanks to the low baud rate, and you have a system so robust that it does not need error correction.
Cool.
See you on the bands!
Ham Radio Operating Ethics and Operating Procedures
In 2008, John Devoldere, ON4UN, and, Mark Demeuleneere, ON4WW, wrote a comprehensive document entitled “Ethics and Operating Procedures for the Radio Amateur.” The purpose of this document was for it to become a universal guide on operating ethics and procedures.
This document was accepted by the IARU (International Amateur Radio Union) Administrative Council as representing their view on the subject. During subsequent Regional IARU meetings it was emphasized that the document be made available to the Amateur Radio Community via all available means, at no cost, and in as many languages as possible.
The document has since been translated into more than 25 languages. In some countries, the document is also offered in printed format and many Amateur Radio websites have a link to the document. Our most sincere thanks go to all our friends who spent hundreds of hours to take care of these translations.
To achieve easier access to all of the existing versions and languages of the document, the authors have set up the Ham Radio Ethics and Operating Procedures web site at:
https://www.hamradio-operating-ethics.org/versions/
It contains a listing of all versions/languages, sorted by country, where you can download the translations in any of the following forms:
*PDF or Word documents from various countries
*Directly from the different Radio Societies’ web sites
*A downloadable PowerPoint Slideshow Presentation (available in one of three languages–English, French and Dutch)
John, ON4UN, and Mark, ON4WW
Windfall for Winterfest 2020!
The opportunity for the St. Louis & Suburban Radio Club Winterfest event to work with the W9DVY Radio Symposium is a fantastic chance for us to help promote vintage radio and the history of the Amateur Radio hobby. We are looking forward to this relationship between the two groups to bring Amateur Radio operators together. We hope to have a strong attendance and we are looking forward to hosting the great Symposium forums. Rebecca Carroll, KC9CIJ – Winterfest 2020 ChairThe Winterfest is located in The Gateway Center, in the shadow of the St. Louis Arch on January 24-25, 2020. No winter weather worries inside the Center! Lots of hotels at various price points nearby. And there are many other activities, such as Contest College with 10+ hours of forums, presentations, Q&A and contesting discussion, as well as the DX & ARRL Banquet and…the ARRL Midwest Conference with CEO Howard Michel and other staffers from Newington. Ward Silver NØAX is the Banquet speaker along with Craig Thompson K9CT on the Pitcairn VP6R DXpedition. Flex Radio Systems will be there as a vendor with their newest SDR technology, among other popular vendors. See the Winterfest website for more details. There is a lot going on, competing with most any regional ham fest in the U.S. So there’s an additional day-long set of forums at a hamfest. What’s big about that? OK, fair question. Do you use phone when you transmit? If so, you likely use Single Side Band (SSB) most of the time, especially on HF. The Symposium is named for Wes Schum W9DYV (in Chicago, as Bob Heil says he always signed). Wes W9DYV was instrumental in getting SSB adopted in the amateur radio community. Some say he’s the Father of Single Sideband (see Ham Nation, Episode 86). Now that’s a big deal, no? A little bit of history, provided by Nick Tusa K5EF. “The Symposium was formed to honor one of amateur radio’s key advocates of the then-new technology, Single Sideband, and his company’s ground-breaking ideas that culminated in the Central Electronics 100V Transmitter. Wes Schum (W9DYV) introduced single sideband to amateur radio in a very big way, beginning in 1951 with is Model 10A sideband exciter and continuing though his company’s eventual ownership by Zenith Radio, Inc.” This picture shows Wes with one of his very early SSB transmitters. I vividly recall hearing the 75 meter AMers calling them “mush mouth” operators. I immediately understood since the old RCA “winking eye” floor model shortwave receiver I heard them on did not have a BFO so as to tune to one side of the bandwidth. Those cat-calls soon faded into obscurity. Today, AM aficionados and SSB mode operators generally habitat HF bands without quarrel, appreciating what Wes Schum’s “appliances” did for the ham radio market and ham radio itself. Nick K5EF continued, “Initially, a group of Central Electronics enthusiasts decided the time had come to try a true boatanchor field day, with Wes Schum as the guest of honor/celebrity roastee. Thus, the first Boatanchor Field Day was born in Jonesborough, Tennessee – June, 2013. Later, and with two vintage field days under our belts, the group next sought to include technical SSB workshops into a Field Day setting and with it the encouragement of homebrewing and documenting the history of the many wonderful and colorful amateur radio manufacturers of the 1950s and 60s. Wes always encouraged learning and creativity in the amateur’s workshop, thus the W9DYV Radio Symposium was born.” Think about that legacy for a moment. Starting a “field day” to honor a member of your club or employer where hams are prevalent just doesn’t happen that much. When it does, it’s because the legacy being continued is a big deal. Like the development of Single Side Band. Today, the Symposium is taking an exciting step forward by holding its event last year in the New Orleans area and now more permanently at Winterfest 2020, to facilitate access to the forums without having attendees travel more than a day’s driving distance. It is important for the Symposium to be affiliated with a hamfest and flea market as its target audience is for those who are: (a) interested in the history of amateur radio and its innovative technology; (b) would like to get more involved in the restoration/collection of vintage equipment and to preserve our heritage; (c) are looking for encouragement to homebrew and experiment; (d) are interested in hearing ideas that can improve every ham’s HF operating experience. Besides … what ham can resist a good radio boneyard? See www.ce-multiphase.com for more photos and information on previous Symposia and the history of this important company, Central Electronics, later part of Zenith Inc. I learned a lot when I spent some time on that website. Like this picture from 1956, when a little dab’ll do you (Brylcreem slogan). The lineup for the W9DYV Symposium at Winterfest 2020 contains a host of well known speakers. Hollow state technology is the theme but—surprise, surprise—high performance SDR kicks off the Symposium. This latest innovation in amateur radio reflects the legacy of how W9DYV launched SSB back in the day! So innovation continues:
- A High Performance SDR Receiver for the Ham-Bob Nichols W9RAN
- HF Receiver Performance-Rob Sherwood NC0B
- Understanding of Human Speech Articulation-Dr. Bob Heil K9EID
- The Collins S-2 Line History and Evolution-Dave Beckler N0SAP
- Wes Schum (W9DYV) and Central Electronics-Nick Tusa K5EF
- Drake T4XC: Low Power Output and Why-David Assaf W5XU
- ARRL, AM and the story of the Gates BC-1T-Bob Allison WB1GCM
- Another “major homebrewer” presentation is pending
Planning a successful, and growing, hamfest takes vision and the willingness to engage “over the transom” opportunities. You might be surprised at the reticence of some well-known hamfest Chairs and Committees to see beyond last year’s program. Frank Howell K4FMHPlanning a successful, and growing, hamfest takes vision and the willingness to engage “over the transom” opportunities. You might be surprised at the reticence of some well-known hamfest Chairs to see beyond last year’s program. Online sales are eroding the ROI that major manufacturers, their resellers, and the small ham radio business companies get by committing thousands of dollars just to get to a hamfest. Individual sales through boneyards can yield surprise inexpensive purchases but, on the average, hamfests face a similar battle with eBay sales, too. It is programs—the continuing education of hams who spend money to attend a hamfest—that bring’em in, repeatedly over the years. And the Winterfest 2020 team is doing that in spades. I asked Rebecca Carroll, Winterfest 2020 Committee Chair, about this year’s events. Here’s what she said, “The St. Louis & Suburban Radio Club Winterfest has added some great events from previous years. We have added floor space to include Education Alley, doubled our forums and increased our operating hours to 4pm. In addition to these changes, Winterfest has been selected as the ARRL Midwest Conference for 2020. The weekend starts on Friday January 24th with the W9DYV Radio Symposium during the day and a DX/ARRL banquet that evening. Saturday January 25th Winterfest kicks off at 8 a.m. with the opening of the sales floor, VE testing, all day topical Forums, and Contest College starting at 1 p.m. with 10 plus hours of contesting forums and discussion hosted by top area contesters. We invite all hams to come to Winterfest for a weekend of Amateur Radio fun.” If you can’t make Tim Duffy’s big shindig at Xenia, the famous Contest University, the St. Louis Contest College is a great option on Saturday at Winterfest. That leaves room for the free Schum W9YDV Symposium on Friday and the (pay) DX/ARRL Banquet that evening. Plus, the next day (Saturday) when the sales floor opens, there’s another set of Forums for the price of entry to Winterfest. Most impressive. As I stated earlier, you’d be surprised at how many hamfest Chairs just follow last year’s program like a mule with blinders, plowing a long row until their successor takes over the reins. Not the SLSRC’s Committee. When I quizzed Rebecca about her vision for Winterfest, I got an impressive response. “We would like to develop Winterfest into another ‘destination hamfest’. Future goals include expanding to a longer hamfest, scheduling more forums, extracurricular activities and growing Education Alley while supporting new and innovative ideas. We would like to build on our previous successes but also adapt to the changing hobby. With the changes in 2020, we hope to continue the momentum and build upon that for years to come. Adding the Symposium, the DX/ARRL banquet and Contest College was a big step for Winterfest 2020 and so far it’s been a well received addition. The key players in getting Winterfest 2020 to this stage include: Kyle Krieg AA0Z, Dale Holloway K4EQ and Pam Caldwell KE0OWG. It takes a team effort.” To examine Rebecca’s point of making Winterfest a destination hamfest, the map above illustrates how many major cities easily within a day’s drive are in the proximity of Collinsville, IL, a suburb of St. Louis. The ham population from the perimeter cities, and their constituent less populated areas, include Chicago, Cincinnati, Louisville, Nashville, Huntsville, Memphis, Little Rock, Tulsa, Omaha, and Des Moines. Add early bird discount airfares from Dallas, Atlanta, Denver, and the like, and they will come. Because of attractive programs. And, because there’s one major hamfest for the St. Louis area, not a dozen. This is a key strategic point regarding the SLSRC. Take Atlanta as a case in point. There are a dozen or so amateur radio clubs in the 20 county Atlanta metropolitan region. And a bunch of smaller hamfests. Vendors do not attend more than one hamfest per market due to the travel and setup investment. (Ask them. I have.) Smaller hamfests tend to have poorer quality venues due to the rental fee structure. (OK, Dayton and now Xenia with Hamvention are exceptions but they have a grandfather clause an arm’s length in size due to history.) The Atlanta area once held a hamfest at the wonderful Georgia World Congress Center downtown adjacent to CNN Center, the World of Coca Cola, the Omni Hotel, the Aquarium, and a myriad of other attractions. But the clubs in Atlanta’s region will not band together to put on a single, knock-your-socks-off hamfest in a great venue, with discounted Delta airfares, and coupons for the other attractions, and major vendors. Oh, the various clubs have great talks at HamJam, Techfest, and in other gatherings but imagine what it would be if they were all at one, single, large hamfest gathering. Cooperation and what social scientists call “social capital,” the ability to make strategic decisions for the betterment of the collective, has largely escaped the various clubs in the Atlanta area. If they’d put all of this together as SCLRC has done in the St. Louis area, Atlanta could become a destination hamfest with a major calendar commitment much as Orlando’s Hamcation has over a decade or so. Of course, those clubs prefer to go their own separate ways and that’s their individual right to do so. Sometimes, though, it leads to canceling the annual hamfest, as the Atlanta Radio Club did last year. So clubs tend to be dying if they’re not growing. See the RSGB Panel discussion a month or so ago led by Martin Butler M1MRB, called Grow, Merge or Disband Your Club. Vision. Collaboration. And a willingness to see a windfall coming your way when it does. The vision of Winterfest, located at The Gateway Center and in the shadow of the major St. Louis attractions, of reaching the goal of a destination hamfest is quite reasonable. Look at how Hamcation in Orlando—say Mickey and the kids are in and say warm weather in February and spouses are in—has grown in the past decade. A quick tour of St. Louis attractions and food venues at, for instance, TripAdvisor.com, makes a clear point of the diversity of non-ham radio things for the family to do. But it takes the vision of leadership by hamfest Committees to understand how to leverage these assets for the benefit of the sponsoring club. Other clubs would do well to study what this one is doing. They may be doing it better but most aren’t. Compete in Field Day but cooperate on hamfests. Like the St. Louis and Suburban Radio Club does. Rebecca and her team, including SLSRC President Kyle Krieg AA0Z, have clearly been organized, progressive, and communicative. I’ll wager a guess that with the addition of the “windfall” of the Wes Schum W9DYV Symposium, Winterfest will indeed move into the destination category of regional hamfests very soon. The radius of a typical regional hamfest’s market area, especially when buttressed by a significant ARRL presence, major vendors like Flex Radio Systems and others, and significant continuing education activities like Forums, Contest College, and the W9YDV Radio Symposium, makes the St. Louis metro area a natural draw from the region. There’s more work to be done by Rebecca and her team, but this “Windfall for Winterfest 2020” is a great launching point!
Oh, They Should’ve … Here’s Why and Why Not on the QSX
How often have you seen into the thinking process of the development engineering team for an amateur radio manufacturer? Or an industrial test and measurements manufacturer of devices used frequently by amateur operators? In the latter case, the HP Journal was (and still is for vintage equipment) a key source for their line of equipment and often had an in-depth article from the engineers who designed one of their popular test devices. Less so but often with the Tek Journal, too. I always see if there’s a “design article” for any HP or Tek vintage equipment before I make a purchase. While MFJ Enterprises frequently gives factory tours, even for a single visitor, Martin Jue rarely gives public disclosures of the thought process of a device. At least, not until it’s well into production and sales.
But Hans Summers G0UPL, recent winner of the Homebrew Heroes Award for 2019, has done just that! In the October issue of QRP Quarterly (Vol 60, Number 4: 24-38), Hans weaves his thinking and design choices for the SSB QSX multiband, multimode 10-watt QRP transceiver. He’s been publicly discussing the concept since 2017 but rarely do we get this level of detail and insight for a major transceiver release. Oh wait. It’s not a product of one of the major manufacturers so what makes it a major product?
Review the QRP-Labs website on the QSX for the interim specifications and feature set. And pay attention to the projected price. Now, let’s revisit the reticence at calling it a major product release. Block diagrams, schematics, mock-up designs, and the pricing-performance choices going into Hans’ decision matrix for each element of the forthcoming rig are there. Even the case and the choice of no hardware volume control! And the choice of a soft switch for power on and off. The inclusion of several test equipment circuits built directly into the transceiver package ramps up what other manufacturers have included. And did I mention that the target price is $150 USD?
Ashar Farhan made a real splash in the QRP homebrew space when he released the Bitx40 ($59USD) and uBitx ($130USD). There is a small army of builders, modders, and third-party add-ons and case makers surrounding Farhan’s products. But reading the target specifications for “just a little bit more” at $150USD on the QSX QRP transceiver (including a nice case), it will set a new bar for the value proposition in the QRP market place!
And who knew how much the inclusion of a “simple” potentiometer for power on/off and volume control could impact the overall design and cost for a multiband transceiver? If you read this article, you’ll be somewhat shocked and amazed at how the designer’s careful analysis of his product target goals factored into the decision to just not include one. But that’s only one of the interesting twists and turns in this intriguing article on the design of the QSX transceiver.
Read the article and see if you agree with my assessment. QRP Quarterly is edited by Mike Malone KD5KXF. It is the publication of the QRP Amateur Radio Club International with an annual subscription price at $25 USD for domestic subscribers and $28 USD for international subscribers. The QRP-ARCI sponsors the Four Days in May Symposium held in conjunction with Hamvention in Xenia, OH. Hans G0UPL is also a member of the QRP Hall of Fame.
The market shall see what the final version, performance, and exact price will be. Reviewers will leave no stone unturned in putting the QSX through it’s paces when it’s available for retail purchase. But very rarely will buyers know as much about a transceiver’s design and why it was so as with the QSX. The snarky reviews that we almost always see of why didn’t “they” do this or that in a rig will almost all have been answered well in advance of the official release of the QSX. While “they” usually represent an engineering design team, QRP-Labs is staffed by one, Hans G0UPL, Hero 2019.
Elecraft KP-1500 Review, Restoring a Halli-Kit HT-40, and Hand-Held Spectrum Analyzers
Stories you’l find in our November, 2019 edition:
TSM’s 2019 Scanner Radio Buyer’s Guide
By Larry Van Horn N5FPW
For scanner enthusiasts, the digital revolution has changed the VHF/UHF radio spectrum that we monitor. Many public safety agencies worldwide, especially in metropolitan areas, have transitioned from analog to digital communications protocols and are utilizing trunk radio technology. There are also many statewide trunk radio systems that are either operational, being built or planned that use trunking and/or digital modes. In this year’s guide, Larry breaks down the lineup of digital vs analog receivers and asks a few personal questions: What do you want to hear in your area and how much do you want to spend?
TSM Reviews: Elecraft KPA-1500 Linear Amplifier
By Mark Haverstock K8MSH
Solar Cycle expectations may lead you to conclude that, to be heard, you should try raising your voice. That’s exactly what the Elecraft KPA-1500 linear amplifier does—and it does so in style. Mark takes a look at this top-of-the-line amplifier and says, “If your budget allows, the KPA 1500 is an excellent choice–especially if you own an Elecraft K3 or anticipate getting a K4. The seamless integration is well worth the price, and even if you have another brand of radio, you’ll find the KPA-150 to be a winner, as it plays well with all rigs.”
RF Explorer ISM Combo+ Slim, Hand-Held Spectrum Analyzer
By Bob Grove W8JHD
Miniaturization of solid-state receivers and panoramic displays has evolved into more compact, even handheld, spectrum analyzers. Bob takes a look at this latest entry into the signals surveillance market and notes, “This handy handful has the ability to display signal presence over a wide range of frequencies as well as digitally analyze and display a variety of data. Added to this flexibility, the unit can also be used as an RF signal generator for the 2.35-2.55 GHz Wi-Fi band, and it includes an analyzer for this band as well.” Best of all—it’s available for under $300.
The Latent Contester
By Cory GB Sickles WA3UVV
Since the time he first became licensed as a Novice in the early 1970s, Cory has tried to experience many of the various aspects of amateur radio. Some have held his interest, some have come and gone and some really never took hold. Contesting was a sub-interest that fell into the latter category. He would periodically dabble with it in various forms then move on to something else. While he admits to possessing a competitive nature, it had never really emerged in the on-air world of amateur radio. Recently, that changed. He had been invited to sit in on a contest at one of this country’s premier contest stations. Now, he’s hooked.
Scanning America
By Dan Veeneman
Iredell County (NC) and Cape May (NJ)
Federal Wavelengths
By Chris Parris
Monitoring Road Trip: Arizona and California
Milcom
By Larry Van Horn N5FPW
DoD Aerial Refueling Frequencies
Utility Planet
By Hugh Stegman
US Coast Guard May Discontinue NAVTEX
Shortwave Utility Logs
By Mike Chace-Ortiz and Hugh Stegman
VHF and Above
By Joe Lynch N6CL
USMA Cadets Contact Alum Aboard ISS
Digitally Speaking
By Cory GB Sickles WA3UVV
Digital Voice Radio Buyer’s Guide
Radio 101
By Ken Reitz KS4ZR
Propagation: Hearing is Believing
The World of Shortwave Listening
By Ken Reitz KS4ZR
A Better Antenna for Better Shortwave Listening
The Shortwave Listener
By Fred Waterer
Radio Tirana; BBC Monthly Programming
Amateur Radio Astronomy
By Stan Nelson KB5VL
Meteor Monitoring Digital TV Carriers on Channel 2
Adventures in Radio Restoration
By Rich Post KB8TAD
The Hallikit HT-40 Transmitter
Antenna Connections
By Dan Farber AC0LW
Do the Math: Numbers Crunching for Radio Enthusiasts
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TX Factor Episode 24 Goes Live
Episode 24 of TX Factor is a Hamfest 2019 special, reporting on some of the eye-catching products and services on display at this year’s event in Newark, UK.
We investigate the current state of HF propagation, celebrate 50 years of UK’s Nevada Radio, Mike tries out a few solder stations, and Bob goes all soft over the VMARS vintage AM radios. And to cap it all, we take a look at the latest rig from Yaesu.
As always, there’s a chance to win a great bundle of prizes from our UK sponsors, ML&S and the RSGB.
We hope you enjoy the show!
Olivia Digital Mode (1000 Hz) on Twenty Meters – A Simple Video
The Olivia digital mode on HF radio is a mode capable of two-way chat (QSO) communication (keyboard to keyboard, like RTTY) over long-distance shortwave (HF) ionospheric propagation paths, especially over polar regions.
If you are interested in more than a logbook QSO (such as is typical with FT8 and other propagation-checking modes) but want to chat with other hams around the world using digital modes, consider Olivia as one option.
This video captures a few moments of two-way conversation on the Twenty-Meter band, up in the sub-band where 1000-Hz digital modes are commonplace. More narrow-bandwidth settings are used in a lower subband in the digital slice of Twenty Meters. More details about the mode are in the files section of this website: http://OliviaDigitalMode.org.
[embedyt] https://www.youtube.com/watch?v=FUjiBVsXrzE[/embedyt]
In 2005, SP9VRC, Pawel Jalocha, released to the world a mode that he developed starting in 2003 to overcome difficult radio signal propagation conditions on the shortwave (high-frequency, or HF) bands. By difficult, we are talking significant phase distortions and low signal-to-noise ratios (SNR) plus multipath propagation effects. The Olivia-modulated radio signals are decoded even when it is ten to fourteen dB below the noise floor. That means that Olivia is decoded when the amplitude of the noise is slightly over three times that of the digital signal!
Olivia decodes well under other conditions that are a complex mix of atmospheric noise, signal fading (QSB), interference (QRM), polar flutter caused by a radio signal traversing a polar path. Olivia is even capable when the signal is affected by auroral conditions (including the Sporadic-E Auroral Mode, where signals are refracted off of the highly-energized E-region in which the Aurora is active).
Currently, the only other digital modes that match or exceed Olivia in their sensitivity are some of the modes designed by Joe Taylor as implemented in the WSJT programs, including FT8, JT65A, and JT65-HF–each of which are certainly limited in usage and definitely not able to provide true conversation capabilities. Olivia is useful for emergency communications, unlike JT65A or the popular FT8. One other mode is better than Olivia for keyboard-to-keyboard comms under difficult conditions: MT63. Yet, Olivia is a good compromise that delivers a lot. One reason for this is that there are configurations that use much less bandwidth than 1000 Hz. 16 tones in 250 Hz is our common calling-frequency configuration, which we use lower down in the Twenty-Meter band, with a center frequency of 14.0729 MHz.
Q: What’s a ‘CENTER’ Frequency? Is That Where I Set My Radio’s Dial?
For those new to waterfalls: the CENTER frequency is the CENTER of the cursor shown by common software. The cursor is what you use to set the transceiver’s frequency on the waterfall. If your software’s waterfall shows the frequency, then you simply place the cursor so that its center is right on the center frequency listed, above. If your software is set to show OFFSET, then you might, for example, set your radio’s dial frequency to 14.0714, and place the center of your waterfall cursor to 1500 (1500 Hz). That would translate to the 14.0729 CENTER frequency.
The standard Olivia formats (shown as the number of tones/bandwidth in Hz) are 8/250, 8/500, 16/500, 8/1000, 16/1000, and 32/1000. Some even use 16/2000 for series emergency communication. The most commonly-used formats are 16/500, 8/500, and 8/250. However, the 32/1000 and 16/1000 configurations are popular in some areas of the world (Europe) and on certain bands.
These different choices in bandwidth and tone settings can cause some confusion and problems–so many formats and so many other digital modes can make it difficult to figure out which mode you are seeing and hearing. After getting used to the sound and look of Olivia in the waterfall, though, it becomes easier to identify the format when you encounter it. To aid in your detection of what mode is being used, there is a feature of many digital-mode software implementation suites: the RSID. The next video, below, is a demonstration on how to set the Reed-Solomon Identification (RSID) feature in Ham Radio Deluxe’s Digital Master 780 module (HRD DM780).
I encourage ALL operators, using any digital mode such as Olivia, to TURN ON the RSID feature as shown in this example. In Fldigi, the RSID is the TXID and RXID; make sure to check (turn on) each, the TXID and RXID.
Please, make sure you are using the RSID (Reed Solomon Identification – RSID or TXID, RXID) option in your software. RSID transmits a short burst at the start of your transmission which identifies the mode you are using. When it does that, those amateur radio operators also using RSID while listening will be alerted by their software that you are transmitting in the specific mode (Olivia, hopefully), the settings (like 8/250), and where on the waterfall your transmission is located. This might be a popup window and/or text on the receive text panel. When the operator clicks on that, the software moves the waterfall cursor right on top of the signal and changes the mode in the software. This will help you make more contacts!
RSID Setting:
[embedyt]https://www.youtube.com/watch?v=lBIacwD9nNM[/embedyt]
+ NOTE: The MixW software doesn’t have RSID features. Request it!
Voluntary Olivia Channelization
Since Olivia signals can be decoded even when received signals are extremely weak, (signal to noise ratio of -14db), signals strong enough to be decoded are sometimes below the noise floor and therefore impossible to search for manually. As a result, amateur radio operators have voluntarily decided upon channelization for this mode. This channelization allows even imperceptibly weak signals to be properly tuned for reception and decoding. By common convention amateur stations initiate contacts utilizing 8/250, 16/500, or 32/1000 configuration of the Olivia mode. After negotiating the initial exchange, sometimes one of the operators will suggest switching to other configurations to continue the conversation at more reliable settings, or faster when conditions allow. The following table lists the common center frequencies used in the amateur radio bands.
Olivia (CENTER) Frequencies (kHz) for Calling, Initiating QSOs
It is often best to get on standard calling frequencies with this mode because you can miss a lot of weak signals if you don’t. However, with Olivia activity on the rise AND all the other modes vying for space, a good deal of the time you can operate wherever you can find a clear spot–as close as you can to a standard calling frequency.
Note: some websites publish frequencies in this band, that are right on top of weak-signal JT65, JT9, and FT8 segments. DO NOT QRM weak-signal QSOs!
We (active Olivia community members) suggest 8/250 as the starting settings when calling CQ on the USB frequencies designated as ‘Calling Frequencies.’ A Calling Frequency is a center frequency on which you initially call, ‘CQ CQ CQ. . .’ and then, with the agreement of the answering operator, move to a new nearby frequency, changing the number of tones and bandwidth at your discretion. Even though 8/250 is slow, the CQ call is short. But, it is narrow, to allow room for other QSOs nearby. It is also one of the best possible Olivia configurations for weak-signal decoding.