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[25 WPM using Straight Key manual keyingDeep, slow QSB,Great Circle Polar path with Auroral pitch dither distortion]

1

CW - The most robust Radio Communication mode / Check your Morse Code decoding skills for CW Radiotelgraphy

« on: March 07, 2021, 13:55:28 UTC »

Are you a skilled CW operator who can comfortably decode Morse code radiotelegraphy transmissions on HF radio bands? Go on, test your skills to find out if you need more practice.

HF radiotelegraphy environment can often be far from ideal. HF radio DX circuits are subjected to a variety of propagation phenomena that might lead to some or all of the following to make life difficult... Are you geared up to negotiate these conditions? Of course, there are many other effects beyond what I have listed below...

• Deep fading (QSB) - It may either be slow or fast in nature that could at times sink the RX signal below the noise floor.
• Background Static Noise (QRN) - At different time, band, and operator's QTH, the magnitude would vary. Lightning and thunder would further add to the noise and crackle on the channel.
• Man-made Noise (QRM) - Not only could the channel be affected by local electrical noise sources but adjacent channel or co-channel interference from other transmissions could produce adverse effects to compound difficulties.
• Multi-path Propagation phenomena - Signal arriving at the receiver could be via multiple ionospheric skip paths that produce amplitude as well as phase distortion on the received signal
• Selective fading and non-uniform Group Delay - This could drastically alter the tonal quality and the pitch of the signal at the receiver. The effect could be time-dependent and result in pitch alteration and flutter.
• Polar Cap Distortion - Many of the intercontinental DX paths have to pass through or adjacent to the polar region. At times when we experience CME and similar solar activities, there is a tendency for increase in Aurora Borealis and Aurora Australis. These result in producing a very hollow sound at the CW radiotelegraphy receiver.

The question is, are you ready to comfortably handle these situations and continue to copy a CW radio transmission with ease? ... Forget the CW decoder software. They will do no good. You have got to be skilled to copy by the ear.

Test your skills below by trying to copy the following recorded transmission.

It is nearly a 35 minutes plain English passage comprising of alphabets, numerals and a few basic punctuation marks. I have not included pro-signs for the sake of simplicity...

The transmission speed is approximately 25 WPM... Now don't say that it is too fast...  If you can't copy at this speed then it means that there is a fundamental flaw in the way you were originally taught how to copy Morse code. You need to address this flaw. I will help you do it with a comprehensive set of CW lessons on this website.

The recorded transmission below, simulates a moderately weak-signal HF DX path that follows a 14000 Km Great-Circle path over the polar region with a moderately disturbed ionospheric condition... There is deep QSB, tonal distortion due to pitch dithering, manual keying using a straight key resulting in a slightly variable weighted character stream, etc... This is as real as it gets. TRY to copy it ALL...

25 WPM using Straight Key manual keying
Deep, slow QSB,
Great Circle Polar path with Auroral pitch dither distortion

Could you copy all of it? Probably not in entirety... That's OK...

Some might have tried to use software decoders. In all probability they failed miserably... All other genuine CW operators who attempted to copy by the ear, here is how you could realistically assess yourself...

• More than 90% copy in one go - You are truly a MASTER of CW Radiotelegraphy... My Respects.
• More than 50-70% copy in one go - You are pretty good but maybe a bit rusty. Practice to sharpen your skills
• Could copy a few sentences at a stretch - You can copy CW, no doubt. However, You are very rusty and mental fatigue sets in quickly. You need to seriously practice.
• Could copy only a couple of words in succession - You have the basic underlying skills. But you tend to lag behind the transmission rate and hence loose it after a few words... Practice at 25 WPM, preferably using Farnsworth method.
• Could only copy occasional alphabets but not complete words - You learned CW the wrong way. You tend to mentally break the characters into dits-n-dahs and do not register them in your mind as a single and homogeneous character sounds. You have hit the speed barrier which can only be overcome be following a proper code learning process... Follow my Morse code lessons that will come up very soon on this website... Stay tuned.
• Could not copy anything. It all sounded so alien - That's very good. It means you have clean slate. You are therefore in a position to learn CW in the proper way from the scratch, if you try... Comprehensive CW lessons are coming up on this website... Stay tuned.

Hope you enjoyed the exercise... 73, de Basu VU2NSB

2

HamSphere Special Activities & Events / Re: India DX Net (IDXN) special session on 3rd March 2021 on HS4 HF band

« on: March 02, 2021, 14:33:24 UTC »

Here are a few important pointers for those who live in the following specific regions and might like to take the challenge of negotiating propagation tomorrow and join the IDX Net on HS4.

The effective SSN has plummeted since yesterday and is expected to reduce further during the duration of the net tomorrow.... Hence, please keep the following in mind.

(1) Operators living in most of Asia, EU, Africa, East-coast of USA, East-coast Canada and central Canada, Caribbean, Mexico, Central America, entire South America except east and central Brazil, and most of Oceania region will have NO PROBLEMS... It should be a cakewalk.

(2) Those in USA and Canada should keep in mind that at the beginning of the net, the east-coast regions will have access. However, with the passage of time, the propagation into states and territories further westward will start opening up. Half way through the net and till the end, the states like Minnesota, Iowa, Dakota, Nebraska, Kansas, Oklahoma,, Texas, New Mexico, etc will manage to access the net... Further down the time, towards the end of the net, stations in Montana, Wyoming, Colorado, Utah, and Arizona should be able to make it, but the caveat is unlike the rest of the USA operators who need only moderate gain antennas to work comfortably into the net, they will require very high gain antennas like the stacked Yagi.

(3) The USA states of California, Nevada, Idaho, Oregon, Washington, Alaska, and Hawaii have practically NO CHANCE due to adverse propagation.

(4) European part of Russia should be able to reach and access the IDX Net during the first half of the session. However, the propagation might close down rapidly for them as the time goes by. Asiatic Russia, Korea, and Japan is not expected to access the net at all.

(5) UK faces a very unique situation vis-a-vis the net-controller's QTH. Almost the entire UK region falls within what is known as the 3rd Skip-zone... This phenomena is a rather unique one. As a consequence, as the earth spins on its axis and New Delhi (VU2NSB QTH) goes into darkness at nightfall, the propagation in the 3rd Skip-zone begins to fail much before the band closes down for the rest of the neighboring regions... Therefore, stations in UK might experience signal loss before the rest of Europe does so.

(6) Finally, our friends in the Tasmania region of Australia might find the conditions rather hostile and unsuitable for almost the entire duration of the net. Although, during the beginning of the net, it will be fine, but as the time progresses the south coast of Australia will begin to loose IDX Net access.... Rest of Australia is expected to come in with strong signals... New Zealand might also lie at the cusp of propagation for a substantial duration of the net. The northern half of New Zealand should do fine but the southern half might struggle.


73, de Basu VU2NSB.

3

HamSphere Special Activities & Events / India DX Net (IDXN) special session on 3rd March 2021 on HS4 HF band

« on: March 02, 2021, 12:37:17 UTC »

IDX Net Announcement!!! - Another Worldwide HF Radio Net Session on Wednesday, 03 March 2021 on HS4

We know that it could be a tall order during the low solar-cycle phase to conduct HF radio net that covers a large portion of the globe simultaneously to span over almost all continents... Nevertheless, India DX Net (IDXN) after due diligence has decided to run the third session since the commencement of this new solar- cycle #25 that has just begun.

On Wednesday, the 3rd March 2021,, starting at around 12:30 - 13:00 UTC, we will run the IDX Net on HS4. We will decide the operating band just before the beginning of the net session based on prevailing propagation conditions...

The objective of the IDX Net session is to dispel the false notion that the HF propagation conditions are poor and also to provide opportunities for everyone to participate in extreme DX communication. The Net will endeavor to be in constant and simultaneous contact with stations from all around the world including, Europe, Asia, Africa, Australia,, New Zealand, Caribbean, and parts of North & South America which poses the biggest propagation challenge for the Net Controller with the QTH in India. Therefore, the participation of operator's from west-coast of NA will probably not be possible, while the east-coast and central USA and Canada should be easy. The net might not be accessible from most parts of South America because the sun will be overhead in the South Atlantic region resulting in a strong ionospheric D-layer producing unacceptable signal attenuation.

The IDX Net controller will maintain continuous contact will stations from all across the world at the same time without missing a beat or swinging his antenna around... Join us from from all across the world and be a part of the magic... And also experience and learn more about the finer aspects of HF radio propagation.

To access a wealth of information and learn more about HF radio propagation, antennas, and other amateur radio related stuff on a continual basis, join our regular net sessions on Mon, Wed, Friday on HS3 at 12:15 UTC on 28.455 MHz and also join the IDX Net Facebook Group at...

https://www.facebook.com/groups/HamSphere.IDXnet.HF.radio/


73, de Basu VU2NSB (Net controller IDX Net)

4

Radio Wave Propagation / HF Radio Ionospheric Propagation metrics based on Solar Terrestrial Data

« on: February 27, 2021, 14:22:05 UTC »

Here are some of the important Solar activity parametric data that  are responsible for influencing the behavior of the Ionosphere on earth. These in turn, are instrumental in determining HF radio propagation conditions on various bands. The information presented here are automatically updated on a regular basis.

The data-set is presented in two formats below. They are the graph format and a tabular metrics format. The graph which displays the history of measured SSN and SFI derived SSN - SSNf(10.7) that prevailed over the last 60 days is updated once a day, while the Solar terrestrial data metrics table is updated on an hourly basis.

The above illustration displays two graphs. The blue colored curve represents the SSN that is measured by counting of observed Sun-Spots at several solar observatories around the world. The red colored curve is derived from the measured Solar Flux Index (SFI). SFI is measured in the microwave band at a wavelength of 10.7 cm (2800 MHz) using a receiver with a capture window of 100 MHz. This is the global standard. The equivalent SSN, designated as SSNf(10.7) is computed from the SFI value using a standardized set of equations. This SFI derived SSN provides us a more realistic correlation to the actual effective SSN that prevails at any point in time... The SFI derived SSN (red curve) is usually a better choice and yields far more accurate results.

This is a Solar Terrestrial Data Metrics Table which is updated every hour at the turn of UTC hour. The table presents several vital parameters which determine the ionospheric condition and HF Radio propagation behavior around the world. Although some parameter change less frequently, there are others that change on an hourly basis.

SSN - The daily SSN values are derived from visual count of sunspots and spot clusters on the surface of the sun between 16-26 degrees latitude of the Sun. They are counted using optical telescopes at various observatories around the world according to "Wolf" method. The observations are collated and averaged to arrive at the global Sunspot Number. A 24 hour smoothed value is presented as SSN. These Daily SSN values are never ever directly used for forecasting or computing propagation conditions. The ionospheric behavior is far more complex than having a direct correlation to daily SSN. Our ionosphere is very lethargic to change and has large inherent momentum.

SSNe - This is the true effective Sunspot number and is as close to realism as it could be. SSNe (Effective) is based on actual hourly measurements of F2 layer Critical frequency (f0F2) taken at 29 distinctively separate geographic locations around the world. The raw f0F2 data drawn from 29 observatories is collated and go through complex computations to arrive at SSNe value. We do automated hourly computations and updates at our end and maintain a database of SSNe values.

SSNe5 - This parameter is a 5 days exponential moving average of the hourly SSNe values. SSNe5 is also computed every hour based on previous 120 SSNe hourly values by deriving an exponential moving average.

SSNf(10.7) - This is the SSN value computed from the Solar Flux Index (SFI). Hourly SFI feed from the value measured by orbiting satellites. SFI data is processed using established algorithms to determine an equivalent SSN value. Since it is derived from SFI this parameter is termed as SSNf.

SSNf90 - This parameter is a 90 days exponential moving average of the hourly SSNf values. SSNf90 is also computed every hour based on previous 2160 SSNf hourly values by deriving an exponential moving average.

SFI - This is the Solar Flux Index (SFI). It is measured using sensitive satellite borne microwave receivers operating at 2800MHz (10.7cm Wl) with a capture bandwidth of 100MHz. The received signal is integrated over the capture (noise) window and the strength of this signal is used to determine SFI.

SFI90 - This parameter is a 90 days exponential moving average of the hourly SFI values. SFI90 is also computed every hour based on previous 2160 SFI hourly values by deriving an exponential moving average.

SWS-T - This is the T-Index from the Australian Ionospheric Prediction Service (IPS). This parameter SWS-T is also another method of measurement similar to SSN but it has no direct correlation to SSN. Like SSNe it also uses a measurement paradigm based on foF2 ionosonde measurements but the methods are different. Although SWS-T is relatively new, it tends to correlate with SSNe values to a considerable extent and appears to be very promising.

X-Ray - This is the measurement of X-Ray at the wavelength of 1-8 Angstrom region (0.1-0.8 nm). Hence it is known as "1-8A X-Ray". The values are typically displayed for instance as B2.4, where "B" represents e-7 (to the power -7). Therefore B2.4 means 2.4e-7. Similarly "A" is e-8 and "C" is e-6 and so on. The measurements are taken by NOAA's GOES satellites with an integration interval of 1 minute. Solar X-ray emissions are measured by sensitive instruments on board GOES satellites. The X-ray radiations from the sun take approximately 500 seconds (8.33 minutes) to cover the distance from sun to Earth. Any solar event like Flares or CME results in sudden increase in X-ray energy emission from the Sun. This in turn reflects itself as enhanced X-ray field strength reaching earth. Though solar X-ray is very important maintaining good ionospheric health and maintain healthy slab densities, excessive X-ray often penetrates deep through the earth's upper atmosphere and the upper ionospheric region to cause excessive ionization at the D-layer region. This could lead to HF communication difficulties or blackouts.

ap Index - This an estimated Geomagnetic Index estimated by integration over 3 hours. ap index is related to the amplitude” of magnetic activity based on K index data from 11 Northern and 2 Southern Hemisphere magnetic observatories between the geomagnetic latitudes of 46 and 63 degrees. ap Index is derived from Kp index and features a scale from 0-400

Ap Index - It is a planetary average of A-Index. This an estimated Geomagnetic Index estimated by integration over 24 hours and presented as simple moving average of 8 values every 3 hours. Ap scale is from 0-400

Kp Index - This an estimated Geomagnetic Index estimated by integration over 3 hours and a planetary average of K Index. This is a different unit of measurement in comparison to Ap. The Kp scale is between 0-9 with a resolution of 0.33 and has a quasi-logarithmic scale. The Kp Index is represented either a centric value like 3o meaning 3.0 or 3- meaning 2.66 or 3+ meaning 3.33 and so on. Kp Index is derived from measurements obtained from 13 geomagnetic observatories between 44 degrees and 60 degrees northern or southern geomagnetic latitude

Happy DXing! - 73, de Basu VU2NSB

5

Announcements / How to join the Forum?

« on: February 14, 2021, 12:28:22 UTC »

Although any Guest on the website may freely browse the contents of our Forum, it would be a good idea to join us by registering your personal account. Registered users of the forum will also be able to post their thoughts and questions on any board of the forum and engage in interactive discussions.

The registration process is free and simple. All licensed Radio Amateurs from around the world as well as virtual radio operators from the HamSphere platform are welcome to join.

To begin the registration process, click on the Register link here or at the top of the forum panel and follow the logical sequence.

• Only licensed Radio Amateurs or HamSphere operators may register with their CallSign as the User Name.
• All registration submissions will be verified against QRZ.com or HamSphere callsign databases as applicable.
• Please use valid e-mail address while registering to secure your account, allow password resets, and receive important notifications occasionally.

73, de Basu VU2NSB

6

Announcements / Forum is now open to all Radio Amateurs for posting and discussions

« on: February 14, 2021, 11:59:29 UTC »

All discussion boards of the forum have now been opened up for regular discussion on a wide range of topics. Amateur Radio operators from around the world are welcome to register their accounts and begin discussion threads.

Please post your thoughts, questions, and queries on any of the topic specific boards on the forum. We encourage peer-to-peer interactions on various matters related to Amateur Radio.

All specific queries pertaining to topics covered through various articles and posts on this website will be answered by Basu (VU2NSB), and other Elmers and seasoned operators. Please feel free to post new topic that you might like to discuss. Request for informative articles and posts related to topics that might not have been covered so far on the website are also welcome. Please make such requests under the appropriate board (section) of the forum.

73, de Basu VU2NSB

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HamSphere Ragchewer's Lounge / Re: Great Rag Chew

« on: February 13, 2021, 14:21:25 UTC »

Absolutely outstanding Dave... I hope more and more operators begin to regularly post summaries of their ragchew activities on the forum. It should act as a motivation for others who might be sitting on the fence and wondering whether to take the plunge...   

de, Basu VU2NSB

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HamSphere Ragchewer's Lounge / Re: Good idea!

« on: February 13, 2021, 14:16:29 UTC »

Thank you Bob for joining this new initiative to increase the number of long and relaxed QSOs conducted on HamSphere. Ragchewing has become a dwindling art amongst hams these days. Let us try to revive it.

73, de Basu VU2NSB

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HamSphere Ragchewer's Lounge / Re: Welcome

« on: February 12, 2021, 15:00:58 UTC »

Felix (HP3FGA), great to have you here on the HamSphere Ragchewer's Lounge. I hope that all of us like-minded people could collectively work to bring back some sanity and a more relaxed QSO environment on the HamSphere system. It would be good for all those people who currently feel marginalized by the fact that HS operators are rarely interested in conducting nice, warm and healthy QSO and unwind themselves... Mostly, they are interested in a quickie and thereafter get away in 30 seconds to hunt for another station. Such QSO are so frustrating, pointless, and mundane. Unfortunately, this is driving away a lot of good ops from HamSphere. Hopefully, we could work to partially reverse this trend.

Thank you for your appreciation of my website in general.

73, de Basu VU2NSB

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HamSphere Ragchewer's Lounge / Re: Welcome

« on: February 12, 2021, 12:00:15 UTC »

It is indeed quite heartening to see several operators joining the forum to participate and support the Ragchew movement on HamSphere platform. Members are invited to freely interact on various topics not only in the HamSphere Ragchewer's Lounge but also on other matters related to Ham radio including Antennas, Propagation, etc.

73, de Basu VU2NSB

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HamSphere Ragchewer's Lounge / Re: This is a great idea

« on: February 11, 2021, 15:07:52 UTC »

You are welcome Wayne... Hopefully we could make it work and motivate people to spend some time relaxing and rag-chewing instead of being on their toes chasing stations for points and awards on a 24x7 basis... 

12

Forum Rules / General rules of engagement

« on: October 02, 2019, 20:41:41 UTC »

Welcome to VU2NSB.com forums.

The objective of this forum is to provide an interactive platform for the members to conduct a healthy discussion on various topics that are relevant to the topic categories. The discussions must be cordial and polite and nothing should be written which could be offensive in nature.

The forum must be used in the spirit of fostering friendship amongst members, for seeking technical information, and for sharing knowledge across the board to the benefit of others.

There should be no activity intended to promote any product(s) or service(s) in any way either directly or indirectly on this forum.

Links to thirds party product(s) or service(s) must not be posted on our forum unless they are absolutely relevant and needed for clarity of the narrative of the post or comment.

No irrelevant posts or comments that are not in line with the forum category should be made on our forums.

The primary language for posts and comments on this forum is English. Although we recognize and respect that all other languages are equally important, in the interest of easy and widespread interactivity across the entire community, all members should use English as the common language. Those who are not well versed in English language communication are requested to make the extra effort of using Google Translate (or any other translation service) to convert their musings into English before posting anywhere on this forum.

Within the framework of these simple rules, please feel free to share your thoughts, ideas, queries, or questions by posting or commenting on the forum.

73, de Basu VU2NSB