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Saturday, May 9, 2020

Are You a Code Warrier?

As of February 2007 the Federal Communications Commission removed all requirements for Morse code proficiency on amateur radio license exams. Many were sad to see the end of the Morse code requirement as hams have sustained this specialized communications language for many years. Known to hams as CW or Continuous Wave transmission, it is the most fundamental of radio transmission technologies in which a carrier wave is turned on and off to form dots and dashes with a telegrapher’s key. Given the technology advancements at the time everyone had to admit that the CW mode of operation had given way to modern text messaging, email and voice data. Ham radio evolved to include RTTY (Radio Teletype) and automated PSK31 and FT8 digital data/text modes effectively rendering Morse code obsolete. These facts aside, CW remains a highly reliable mode of communications when others might fail and is still popular with hams the world over.

I obtained my novice license in 1967 when the Morse code requirement was five words per minute with thirteen words per minute for the General and Advanced class exams. A Novice license term was one year and without an overlapping General Class upgrade you were off the air. No way.  Several months into my Novice term I obtained my General ticket and shortly afterward my Advanced Class license. The Extra Class exam required twenty word per minute proficiency and having obtained an Advanced Class license (my current license) I decided to defer an Extra Class license upgrade till my retirement years. My retirement years have arrived, the Morse code requirement is gone and I’m planning an Extra Class upgrade soon.

That said, I’ll recount some valuable Novice experience as insight to newer hams pondering the craft of CW. When other voice and data modes might fail, a skilled and persistent CW operator will succeed. Upon passing my Novice license exam I immediately ordered three quartz crystals from Texas Crystals (a forerunner of today’s Texas Instruments).

FCC rules required Novice operation with crystal control, no VFOs (Variable Frequency Oscillators) allowed. Note that in the 1960s frequencies were designated in Kilocycles and Megacycles until the NBS (National Bureau of Standards) became the NIST (National Institute of Standards and Technology) and Hertz (cycles per second) replaced the Kilo-Megacycle convention.

Anticipating operation on the Novice 40 Meter band; 7.150 to 7.200 MHz, I ordered crystals for 7.153, 7.155 and 7.158 MHz. The crystals arrived in the mail and that evening I went on the air as WN4JVJ, a CW Novice. DX propagation was excellent as the sun was at solar maximum. The 40 Meter band was packed and a very large AM broadcast signal occupied 7.150 MHz. It was Radio Moscow [1] whose typical power output peaked at one Megawatt. Radio Moscow’s AM bandwidth spilled well above and below 7.150 and appeared to render my selection of 7.153 a poor choice. During the 1960s many Short Wave broadcast stations took residence in the ham bands and my other crystal frequencies provided no clear channel advantage. Recalling the old adage “Work with what you’ve got”, I went on the air. With my brass pounder’s key I tapped out a CQ on 7.153. Because Novice’s operated on fixed crystal frequencies you would rarely hear a response on your own transmitter frequency. Operating technique required calling CQ on your crystal frequency and then listening for a response, searching adjacent frequencies and acrossed the band for someone keying your call sign. After calling CQ several times I thought I heard a response near my own frequency. I chuckled to myself thinking another ham had made a poor choice of crystal frequency, but within the envelope of Radio Moscow’s one Megawatt upper sideband I could hear the faint heterodyne of a CW station calling me. It was another Novice station in Virginia, closer than Radio Moscow but almost overwhelmed in the QRM (interference). Novices were limited to 75 watts of transmitter power output but physics intervened to make the signal readable.  When two radio carrier waves are close enough in frequency and overlap they heterodyne to form a tone known as a “beat” frequency.  Early ham radio receivers were designed to receive AM (Amplitude Modulated) voice signals but were also equipped with a BFO or Beat Frequency Oscillator. The BFO could be switched on to inject a receiver generated carrier signal which would beat against selected CW reception.  An audible interference tone resulted from the opposing carriers providing the familiar CW tone/note we hear in our headphones or speaker. A good CW operator can copy signals through seemingly insurmountable interference.

The human brain is a remarkable signal processor. A good CW operator can focus the mind to sift through static noise and interference to copy CW messaging with great accuracy. During the last months of my Novice term I logged for a veteran CW operator on Field Day. During the contest Arnie worked CW exclusively averaging 25 words per minute (my estimate). I improved my CW speed significantly by copying and logging the contacts he made and gained valuable operating experience along the way. After a few hours Arnie seemed to sense this and began to point to the left or right above the Drake Twins (radios T4X and R4B). Not sure what he meant I removed my headphones and asked. "What are the hand signals for?" He laughed and explained he was spotting signals for me to pre-log. As he was working one CW station he would simultaneously copy another he could hear within the receiver’s bandpass. If I could log them in advance we would save time and work more contacts in the contest time allowed. If he pointed left it meant the station he wanted pre-logged was below the tuner curser. If he pointed right the target station was above the tuner curser. Laughing out loud I asked, “How do you know if they’re above or below?” He laughed in return explaining the pitch of the heterodyne note made by his intended target was either higher or lower in tone indicating its position above or below our dial frequency. I laughed again in amazement and began following hand signals while listening high and low.  While Arnie would listen to the tone of a CW signal to determine its location within the bandpass, today's SDR displays enable us to see the RF spectrum above and below our operating frequency. 

Note the vertical curser mark above the spectral display shown below.  You can visually spot the Single Sideband traffic +/- 20 KHz on either side.



I'll pause here for a side note: A frequent curiosity is how Morse code speed might equate to a bps data rate.  As explained by N2EY, [2] (scroll down the linked page)  "Paris" is used as a five letter test word to compute per minute code speed; Paris sent fifty times in one minute equals fifty words per minute. By totaling the dit times, (that is the dahs (three dit lengths) dits and spaces between words), this fifty word per minute CW speed represents 2500 dit times or 41.66 bps.  By extrapolation we can surmise a ham who copies CW at 25 words/min copies an approximate data rate of 20.83 bps. Machine code for the mind?

After several hours our CW shift concluded and another Field Day operator/logger team relieved us. I shook hands with Arnie and thanked him for a great lesson in CW operating skills. We departed with another great laugh as we exited the mobile van housing our Field Day station. It was three or four AM as I began walking toward my car when I stopped in my tracks to copy CW traffic. Had I left my headphones on? No. I listened again intently and realized I was trying to copy the crickets in the woods. Another great laugh (at myself). My mind had become so conditioned to copy CW that everything, every noise I heard was being processed as Morse code. Enough ham radio for one weekend. Time to go home. My girl friend awaited.

We might think CW a lost art but a few weeks ago I tuned around to hear new General and Extra Class operators QSO on CW at five to ten words per minute. Using straight keys they brought back memories of the not so old days. CW has regained popularity as hand held decoders can now scroll received data.  Computer based software is available for contest logging and the automated send/receive of CW.  If you've been to a recent Hamfest you might have seen the new product lines of straight keys, semi-automatic and Iambic electronic keyers.

Many new technology toys await hams as the spring season draws near. What was old becomes new again.  Wishing you good DX.  Be safe everyone.

Have a great weekend!


Best regards,
 
Thomas D. Jay

W4TDJ  Member ARRL
Thomas.Dale.Jay@gmail.com
TDJ Technology Group.com
Thomas D. Jay YouTube Channel









Corporate, private entities or publications referenced or linked in this article are the respective owners of their logos, trademarks, service marks, media content and intellectual property. Unless otherwise disclosed, Thomas D. Jay has no financial interest in companies referenced in blog articles or other published media communications. Thomas D. Jay is not a registered financial advisor.  No representation is made to either buy or sell securities. Opinions expressed by Thomas D. Jay are his own. Thomas D. Jay does not employ or otherwise utilize/authorize third party agents to express his opinions, represent his interests or conduct business on his behalf except where formally contractually designated.  Thomas D. Jay opts out of requests to share personal information or unidentifiable user data. Thomas D. Jay does not agree to indemnify or hold harmless vendors, clients or third parties to related contractual agreements and reserves the right to applicable legal remedies in lieu of arbitration.  Thomas D. Jay retains all copyright and moral rights to his published material, content and brand marketing, and shall in no case be represented, depicted or characterized by parties/entities other than his published "About Thomas D. Jay" descriptor. Contractual agreements are to be written and interpreted in the English language and are subject to the laws of the United States. These terms and conditions shall supersede any conflicting agreement. Clients, vendors and concerned parties should check my blog site at www.thomasdalejay.blogspot.com for periodic updates or changes to theses terms.


References and acknowledgements:

[1] Radio Moscow


[2] N2EY



















Saturday, April 18, 2020

How's DX?



Given the social isolation imposed by the Covid-19 virus I’ve resumed interest the pursuit of DX. In ham radio jargon DX means distance. In casual conversation hams might ask one another “How’s DX”? Translated for non-hams this means “How’s propagation? Is distant radio communication optimal? A major interest for many hams is the ability to speak to others in far off exotic locations wirelessly. During the 1970’s the sun spot cycle peaked and optimally effected the ionosphere. Radio signals reflected off the upper atmosphere so efficiently that with 100 watts of power or less it was possible to talk with other hams all over the globe. While living in New York I could routinely contact the ham shack at McMurdo station on Antarctica, call sign KC4USV. [1] Both our signals were typically + 20 db over S9, enormously strong considering we were over 9,000 miles distant. We might not think of the frigid south pole as Shangi-La but it qualified as exotic DX, a distant location inaccessible to most excepting our military, well funded explorers and ham radio operators on the air.

As DX communication is challenging during the current solar minimum, innovative hams are constantly testing the ionosphere in search of band openings. Optimal DX propagation can occur suddenly during unpredictable solar flare activity. To test conditions hams will often broadcast a CQ, an invitation/call to others listening to engage in conversation. Hams calling CQ DX are searching for radio contact with distant stations in other countries. Occasionally hams will organize a DXpedition; a group of hams will travel to an exotic location, set up a radio station and become a highly sought contact pursuit by other operators seeking a “Worked All Countries Award”.

Testing DX conditions can be challenging. It’s difficult to evaluate the ionosphere when no signals are present. In this regard, DX beacons are helpful. There are many automated radio stations covering our globe which transmit beacon signals. As “radio light houses” their signals can be heard distantly when atmospheric conditions are optimal. DX conditions can also be determined by monitoring scheduled networks. Hams maintain daily “nets” over a wide rage of frequencies. Net control operators for these nets are volunteer hams operating in shifts. Two popular HF (High Frequency) nets can be heard on 14.300 MHz. During morning hours the Intercon Net is active. The Intercontinental Amateur Traffic Net [2] acts as a check in center for hams monitoring the frequency. Hams can obtain signal reports, weather condition updates and check in to rendezvous with distant friends. At 12:00 PM the Intercon Net closes and the Maritime Net resumes its net activity on 14.300 MHz. Known formally as the Maritime Mobile Service Network, [3] this volunteer group is a valuable resource to licensed hams on sea bound traffic ranging from pleasure craft to large commercial shipping, cruise ships and sometimes military vessels. Similarly, the Maritime Mobile Service Network broadcasts weather conditions to ships at sea and sometimes relays messaging to land based systems. In addition to VHF/UHF I also have an HF radio in my car. While mobile I listen to the nets on 14.300 for propagation conditions and obtain signal reports. Once you’ve checked in you’re logged into their computer system for future reference. It’s often surprising to be greeted by name upon your call sign check in. Both of these nets are very popular and supported by a huge following of the ham radio community.

When mobile, seaborne or in the air (airplanes), hams frequently exchange grid square information. In addition to simple location plotting, grid map information can assist with aiming directional beam antennas and navigation. The ARRL explains the origins of the Maidenhead Locator System. [4] HA8TKS provides an excellent Maidenhead grid location utility on a zoomable map. [5] Such resources and utilities simplify global communication coordination for mobile operators and systems.

Did I mention that ham radio and DX are great fun?

Have a great weekend!


Best regards,
 
Thomas D. Jay

W4TDJ  Member ARRL
Thomas.Dale.Jay@gmail.com
TDJ Technology Group.com
Thomas D. Jay YouTube Channel









Corporate, private entities or publications referenced or linked in this article are the respective owners of their logos, trademarks, service marks, media content and intellectual property. Unless otherwise disclosed, Thomas D. Jay has no financial interest in companies referenced in blog articles or other published media communications. Thomas D. Jay is not a registered financial advisor.  No representation is made to either buy or sell securities. Opinions expressed by Thomas D. Jay are his own. Thomas D. Jay does not employ or otherwise utilize/authorize third party agents to express his opinions, represent his interests or conduct business on his behalf except where formally contractually designated.  Thomas D. Jay opts out of requests to share personal information or unidentifiable user data. Thomas D. Jay does not agree to indemnify or hold harmless vendors, clients or third parties to related contractual agreements and reserves the right to applicable legal remedies in lieu of arbitration.  Thomas D. Jay retains all copyright and moral rights to his published material, content and brand marketing, and shall in no case be represented, depicted or characterized by parties/entities other than his published "About Thomas D. Jay" descriptor. Contractual agreements are to be written and interpreted in the English language and are subject to the laws of the United States. These terms and conditions shall supersede any conflicting agreement. Clients, vendors and concerned parties should check my blog site at www.thomasdalejay.blogspot.com for periodic updates or changes to theses terms.


References and acknowledgements:

[1] McMurdo station on Antarctica, call sign KC4USV

[2] Intercontinental Amateur Traffic Net

[3] Maritime Mobile Service Network

[4] The ARRL explains the origins of the Maidenhead Locator System


[5] Maidenhead grid location utility  HA8TKS












Saturday, April 11, 2020

Social Isolation at the Speed of Light


I originally posted this article on my technology web site TDJ Technology Group.com. As it relates to amateur radio I've decided to post it on my ham radio blog as well.  Please keep in mind I was writing for non-ham technologists.  Here goes:

After weeks of news media frenzy on the Covid-19 epidemic we’re all weary of the social isolation imposed on friends and families. Many stay connected via television, and social media but another social network remains unseen to most. Amateur radio operators (known colloquially as ham operators) populate their FCC licensed radio spectrum sandwiched between commercial radio and TV channels. There are over 764,000 federally licensed hams in the US, with several million internationally. In spite of Covid-19, the global ham radio community remains actively social, communicating long distance wirelessly.

By day I’m an investor, writer and technology consultant. After hours the large computer screen on my desk becomes an SDR display for my amateur radio station (SDR is Software Defined Radio). Last night I tuned in to monitor several ham radio contest events. The month of April features many Spring season “QSO parties”. A QSO party is a contest in which hams make radio contact with as many other stations as possible in a predetermined time period (usually a day or two). WA7BNM (Bruce Horn) publishes a comprehensive list of ham radio contest schedules with eight events scheduled this April. [1] Thanks Bruce for a great resource.  

As a hobby, amateur radio has evolved to a new level of sophistication. SDR is Software Defined Radio. Recent adaption of FPGAs (Field Programmable Gate Arrays, a specialized ASIC device technology, (Application Specific Integrated Circuits) found in communications electronics now provide a graphic view of the RF spectrum and its radio signal inhabitants. Utilizing “direct RF (Radio Frequency) sampling” techniques, ASIC technology extracts a radio’s received spectral data and displays it on a computer screen much as an integer number line, or in this case a spectral line extending above and below the zero point frequency (with zero referencing the radio’s tuning dial pointer). SDR graphic displays have revealed that as ham radio operators, we also comprise a real life “Matrix”. Hams populating their FCC allocated radio spectrum can be seen as individual signal traces along the spectral line. The signal traces scroll over time on a “water fall” display leaving after image “foot prints” behind. Run the embedded YouTube video I’ve prepared and you can see the spectral display I’ve described (approx 2 minutes run time). [2] The signals you can hear are captured by the tuner centered on the spectral display. Switching display modes can also provide an oscilloscope view of the signal’s audio envelope. In the past, radio receiver display technology was little more than a box with an inscribed tuning dial. SDR technology was first seen in military applications but now enabling ASIC device technology is also utilized in many automotive and consumer products. The display images in my video were taken from my Icom IC-7610 transceiver. Icom’s first SDR radio the IC-7300 features an Altera EP4CE55F23I7N Cyclone IV E running at 200MHz) which facilitates simultaneous audio processing and graphic display of this information. Advanced specifications aside, SDR has helped enhance the “social” aspect of our hobby. At a glance hams can “see” live radio spectrum to quickly identify lone signals or clustered contest/network activity. Tuning the radio is simplified. Point at a signal trace on the graphic display and a mouse click will tune there instantly, minimal dial tweaking necessary.

Ham radio contest enthusiasts empowered by SDR have infused the community with new interest. Many of these social contest events feature highly coveted award certificates. A few examples are: The DX Century Club award, (DX meaning distance) is presented to operators confirming contact with one hundred international stations. Similarly there’s a Worked All Countries award, Worked All States award and Worked All Counties Award (challenging as you must confirm radio contact with hams populating every state county in the US). 
In spite of the Covid-19 epidemic amateur radio remains a vibrant, socially active hobby connecting hams globally. In times of emergency, natural disasters, or communications outages, hams provide a volunteer base of highly skilled communications operators with global reach. Although there’s been no call for ham radio communications during the current Covid-19 epidemic, a valuable volunteer resource stands ready. In the interim, social distancing at light speed is great fun. Dropping out of warp now. See you on the web.

For additional background on SDR technology see my March 2017 article “New Trends in The Field Programmable Gate Array Market - Software Defined Radio”.  [3]

For additional information on Amateur Radio see the American Radio Relay League web site. [4] 

Stay safe out there.   

Regards to all,
 
Thomas D. Jay

W4TDJ  Member ARRL
Thomas.Dale.Jay@gmail.com
TDJ Technology Group.com
Thomas D. Jay YouTube Channel









Corporate, private entities or publications referenced or linked in this article are the respective owners of their logos, trademarks, service marks, media content and intellectual property. Unless otherwise disclosed, Thomas D. Jay has no financial interest in companies referenced in blog articles or other published media communications. Thomas D. Jay is not a registered financial advisor.  No representation is made to either buy or sell securities. Opinions expressed by Thomas D. Jay are his own. Thomas D. Jay does not employ or otherwise utilize/authorize third party agents to express his opinions, represent his interests or conduct business on his behalf except where formally contractually designated.  Thomas D. Jay opts out of requests to share personal information or unidentifiable user data. Thomas D. Jay does not agree to indemnify or hold harmless vendors, clients or third parties to related contractual agreements and reserves the right to applicable legal remedies in lieu of arbitration.  Thomas D. Jay retains all copyright and moral rights to his published material, content and brand marketing, and shall in no case be represented, depicted or characterized by parties/entities other than his published "About Thomas D. Jay" descriptor. Contractual agreements are to be written and interpreted in the English language and are subject to the laws of the United States. These terms and conditions shall supersede any conflicting agreement. Clients, vendors and concerned parties should check my blog site at www.thomasdalejay.blogspot.com for periodic updates or changes to theses terms.


References and acknowledgements:

[1] WA7BNM, Bruce Horn web site. 
https://www.contestcalendar.com/index.html  

[2] Thomas D. Jay, YouTube Channel Video 
https://youtu.be/fMkHVz23lkw

[3] Thomas D. Jay, Blog article, New Trends in Field Programmable Gate Arrays
https://thomasdalejay.blogspot.com/2017/03/new-trends-in-field-programmable-gate.html 

[4] American Radio Relay League web site
arrl.org








Thursday, September 28, 2017

The American Red Cross Asks ARRL for Assistance with Puerto Rico's Hurricane Relief Effort


As an FCC licensed amateur radio operator (ham radio), I hope to assist in conveying emergency communications information given the power and communications blackout in the Caribbean. Ham radio operators are mobilizing to assist the Red Cross with health and welfare messaging between family and friends in a post hurricane/recovery environment. You may find the following information of interest:

The Red Cross is operating many relief shelters in Puerto Rico and the Caribbean. The Red Cross is also requesting up to 50 FCC licensed ham (amateur radio) radio operators to assist with the relief effort. If you are a ham and can volunteer on-site assistance in Puerto Rico, click on this link:
http://www.arrl.org/news/american-red-cross-asks-arrl-s-assistance-with-puerto-rico-relief-effort

To contact family or friends unreachable after the recent hurricanes, Harvey, Irma, Maria, click on the Red Cross Safe and Well link below. In the upper right select English or Spanish language format. Click on “list myself as safe and well” or “search registrants” to locate someone who has posted a safe and well listing with the Red Cross. The Red Cross will coordinate these message postings and respond via email if possible. https://safeandwell.communityos.org/cms/index.php

If you think your friends or family have left their home and are in a Red Cross Shelter, you might want to search for the shelter location nearest their home or business.

To find active (open) RED Cross Shelters in Puerto Rico, the Caribbean (and globally). Click on the link below. Click and drag to the portion of the global map of interest. Click on the specific area of interest. Zoom in (mouse wheel) to see the area’s active Red Cross Shelters. Click on the shelter’s icon to identify the site and location. The bottom of the page will list the near by shelter’s specific location info. Safe and well listings can indicate shelter sites if you want to post your current location (see safe and well above). http://maps.redcross.org/website/maps/ARC_Shelters.html

Recent Related News Links from ARRL web site postings (The American Radio Relay League)

http://www.arrl.org/news/amateur-radio-volunteers-aiding-storm-ravaged-puerto-rico-us-virgin-islands 
 
http://www.arrl.org/news/american-red-cross-asks-arrl-s-assistance-with-puerto-rico-relief-effort

See this ARRL web page for more emergency communications/relief news and links:

http://www.arrl.org/hurricane-maria-2017

Main web sites for more info:
www.redcross.org

www.arrl.org


Regards to all,

Thomas D. Jay,
W4TDJ

Thomas.Dale.Jay@gmail.com


W4TDJ.com

TDJ Technology Group.com

Thomas D. Jay, YouTube Channel

Corporate, private entities or publications referenced or linked in this article are the respective owners of their logos, trademarks, service marks, media content and intellectual property. Unless otherwise disclosed, Thomas D. Jay has no financial interest in companies referenced in blog articles or other published media communications. Thomas D. Jay is not a registered financial advisor. No representation is made to either buy or sell securities. Opinions expressed by Thomas D. Jay are his own. Thomas D. Jay does not employ or otherwise utilize/authorize third party agents to express his opinions, represent his interests or conduct business on his behalf except where formally contractually designated. By default Thomas D. Jay opts out of requests to share personal information or incidentally collected unidentifiable user data. Thomas D. Jay does not agree to indemnify or hold harmless vendors, clients or third parties to related contractual agreements and reserves the right to applicable legal remedies in lieu of arbitration. These terms are subject to change. Concerned parties should check this blog site for periodic updates.