GRHub Network live stream ARISS contact of students at Carter G. Woodson Middle School, Hopewell, VA, USA (28 February 2022 16h43 SAST)

Amateur Radio on the International Space Station (ARISS)  has received schedule confirmation for an ARISS radio contact with astronauts.  ARISS is the Group that puts together special amateur radio contacts between students around the globe and crew members with ham radio licenses on the International Space Station. (ISS)

The contact was live streamed by the GRHub Network onto Echolink (ZS1I-L), AllStar (49355) and the 145.550 Mhz Simplex Link in the Mossel Bay area as scheduled for February 28, 2022 at 9:43 am EST ( Virginia, USA), (14:43:53 UTC, 8:43 am CST, 7:43 am MST and 6:43 am PST 16:43:53 SAST) . 

Unfortunately from now on there will be no recorded audio file available on the Blog of the contact.  I encourage radio amateurs to connect to ZS1I-L on Echolink or 49355 on AllStar to listen to future contacts. Future contacts will be advertised on Echolink as "ISS contact 16h43 SAST" or on the GRHub Network Blog

It was a telebridge contact via amateur radio and students took turns asking their questions to Astronaut Thomas Marshburn, amateur radio call sign KE5HOC. Local Covid-19 protocols were adhered to as applicable for each ARISS contact. The downlink frequency for this contact was 145.800 MHZ and may have been heard by listeners that are within the ISS-footprint that also encompasses the telebridge station in the USA.

Amateur radio operators in Greenbelt, Maryland, USA used the call sign K6DUE to serve as the ARISS relay amateur radio ground station (telebridge station). 

As time allowed, students asked these questions:

1. What made you want to live in space?
2. How do you not run out of food and where does it come from?
3. Have any animals ever been on board the ISS?
4. How do you return to Earth?
5. What meals do you eat in space?

6. What is your helmet made of and how does it work?
7. How many miles does the ISS travel in a day?
8. What do you do when you are not performing experiments or working on equipment?
9. When you return back to Earth, do you experience any side effects from being in space for 6 months?
10. What scientific discoveries have you made on board the ISS?

11. What have you learned while on board the ISS?
12. What is a goal you have during your mission?
13. What kind of weather do you experience on board?
14. How do you get water?
15. What equipment do you need for a spacewalk?

16. What does the moon look like from the ISS?
17. Do you have doctors on board to help when you get sick or injured?
18. How long does it take to get used to sleeping on a wall?
19. How did it feel traveling up to the ISS?
20. How do you train to live in a low gravity environment?

About ARISS:

Amateur Radio on the International Space Station (ARISS) is a cooperative venture of international amateur radio societies and the space agencies that support the International Space Station (ISS). In the United States, sponsors are the Radio Amateur Satellite Corporation (AMSAT), the American Radio Relay League (ARRL), the ISS National Lab-Space Station Explorers, Amateur Radio Digital Communications (ARDC) and NASA’s Space communications and Navigation program. The primary goal of ARISS is to promote exploration of science, technology, engineering, the arts, and mathematics topics. ARISS does this by organizing scheduled contacts via amateur radio between crew members aboard the ISS and students. Before, during and after these radio contacts, students, educators, parents, and communities take part in hands-on learning activities tied to space, space technologies, and amateur radio. For more information, see www.ariss.org .

 

 

IAXRPT AllStar Fix: IAXRPT client will not connect to any AllStar node after new HamVoip update

Image:  Iaxrpt main window.  (Click on image for larger view.)

The title says it all.  I updated my AllStar (49355) HamVoip firmware recently to the latest version.  This went smoothly, however my IAXRPT Windows Client would not connect to any of my nodes.  If other users of AllStar runs in to the same issue here is the fix.

" Note:  If you're a user of Zoiper, DVSwitch Mobile, IAXRPT or other IAX client software, these clients may NO LONGER CONNECT to your AllStar Nodes without a minor configuration change on the  HamVoIP node.  As of this software release, the IAX2 protocol has "call tokens" ENABLED. This is a VERY IMPORTANT security mechanism, which classically was always forced off in the AllStar software.  This is now changed.  To allow connections from software not supporting call tokens, simply modify the iax.conf file incoming stanza."

For example:

; iax.conf

[iaxphone]

requirecalltoken=no

Above:  Image of the iaxrpt.conf file.  For security reasons I removed passwords and IP Addresses.

After this update to HamVoip v 1.7,  I could connect again but the iaxrpt keypad and DTMF Keypad still did not want to function.  After some searching I found that the following three lines must be added to the rpt.conf file.

propogate_dtmf=yes

propogate_phonedtmf=yes

remote dtmf allowed=1

After adding the above three lines to rpt.conf everything was working as before and I could once again use the iaxrpt windows program without any issues.

I trust that the above will assist Iaxrpt/AllStar users when iaxrpt on Windows 7 - 10 would not connect since the most recent hamvoip update.  The above solved all my issues that I experienced after the update.

New mast project for the GRHub Network 145.550 Mhz Linked Radio

As indicated before the current antenna for the GRHub Network 145.550 Mhz Linked Radio is only about 2 meters above roof level.  Many radio amateurs cannot access the 145.550 Mhz link due to current installation position of the antenna.  I received several request from local radio amateurs to please extend the mast for the Diamond X50 antenna currently in use.  I was looking to build a 300 x 300 x 300 galvanized tower but the current cost of metal and galvanizing does not justify spending a few thousand rand now, as I plan to move to a retirement village in the near future.  As yet I have not taken a decision on whether I will stay in Mossel Bay or move somewhere else.  So the best alternative option is to use what I have on hand.  I have a solid aluminum flag pole as can be seen in the image.  I needed a base plate and concrete block as well as a few other pieces of metal to erect this flag pole and install the Diamond X50 to it.  This flag pole is really ideal, lightweight, easy to erect and can be extended to 12 meters in height by adding a 6m thick-walled aluminum pipe to the top.   I started constructing the base plate which will be bolted with 20mm bolts.  The pole will be kept upright by the pedestal and a metal bracket mounted to the wall where the mast will be erected.  If I go the full 12 meters I will add guy wires.  At first I will erect the mast as portrayed in the photo.  If I am not happy with the coverage area I will extend the mast to 12 meters.  As inflated prices makes it nowadays difficult to purchase necessities I will use what I have on hand.  Hot galvanizing the metal parts will cost me about R400 for petrol alone and a further R25 a kilogram for galvanizing.  I am looking at going the cold galvanizing route as by the time the metal starts rusting eventually I will not be living at my current residence.  Updates to follow regarding the mast project.

Here is a few images:  (Please note that all metal parts are currently only spot welded) 

 

GRHub Network now has an active ZELLO Channel

 

UPDATE 27/2/2022:  Welcome to all those who joined the GRHub Zello Channel.  Lookout for upgrades and possible linking to the GRHub Network.

Zello is useless and not amateur radio - what will you do when the Internet is offline?

This is only one remark from one radio amateur that does not like Zello and therefor running it down as not being amateur radio. Yes sure, it is written on the wall by some radio amateurs who does not like the Internet of Things. If you want to stick to the old-school speech, that’s fine, but you will need a better excuse than saying "Its not Amateur Radio!".  My good advice to those against Zello is to keep your opinion regarding Zello to yourself as you do not have a clue about the functionality of Zello and how you can use it very effectively in amateur radio to recruit new blood to amateur radio, especially the youth. Two years ago Zello was used to relay amateur radio conversations to newbie radio amateurs that were waiting for their callsigns to operate.  This kept them informed and was a great source to learn more about amateur radio.

Now this post is not about whether Zello is amateur radio or not.  I recommend you read the following post to gain more info on Zello and how it is being used in Amateur Radio: Network Radio – Is it real Ham Radio?

The GRHUB NETWORK CHANNEL is being used to forward amateur radio information amongst the public, first responders, NGO’s and radio amateurs for the Africa continent.  This is not all we use this channel for we also relay amateur radio news bulletins, podcasts,  and for that matter any amateur radio related audio like the UK Network Radios Channels and Echolink audio link M0HOY-L aka UK Hubnet etc.  This way the youth and the general public has immediate access to amateur radio audio transmissions to listen to on cellphones with the Zello App.  They do not have to buy an expensive general coverage receiver or illegal scanner to listen to amateur radio broadcasts.  Bonus, they can listen to amateur radio audio anywhere where there is cellphone reception. 

To join the channel search for GRHub Network, Mossel Bay via your Zello application and request authorization.  Please ensure that the channel name is correctly spelt as underneath, otherwise you will not find it.  Channel Name:  GRHub Network, Mossel Bay

I have a few other ideas and uses relating to Zello but more on this in a future blog post.


Hope to hear you soon on the GRHub Network, Mossel Bay Channel!!

FINDING MH370: New breakthrough could finally solve missing flight mystery. Can it really?

UPDATE:  The audio file relating to the video was transmitted on the GRHub Network at 20h00 on 25 February 2022.  If Richard's theory prove to be true and the aircraft is found it would mean so much for amateur radio and the families and friends of the passengers that were onboard the flight.  Let's hope that Malaysia Airlines will give the go ahead for a final search and that Richard can lead them to the final resting place of the aircraft.

Is the biggest aviation mystery of all time, the disappearance of Malaysia Airlines flight MH370, about to be solved by studying amateur radio signals on the night of the fatal flight.   Richard Godfrey says he found the aircraft.  Take a look at the video and judge for yourself if Richard's theory could solve the flight mystery.

Feedback: " THE NSN NET #3" – Thursday 24 February 2022 19h30 SAST

 

I received a request from overseas viewers to please give feedback in English as they don't understand Afrikaans.  The decision was taken to provide feedback in English.

Firstly a big thank you to the following radio amateurs that reported into the Net last night.  We had a great time with interesting discussions!!  As  stated before, those that participated in the Net ensure the continuation of the Net.  The Net  is not a one person en-devour but belongs to every radio amateur that participate.  However it does not belong to listeners as they do not contribute to the Net in any way.  I therefor ask listeners to report in by just telling us that you will be listening or to actively participate.  Just a reminder the net is not a club affiliated net and is open to all radio amateurs.

The following radio amateurs, repeaters and links were logged:

1.  Marco ZS1NEU
2.  Thys ZS1TBP
3.  Johan ZS1I
4.  Tjaart ZS3DR
5.  Janco ZS6LVJ
6.  Stewart ZR6WT
7.  Danie ZS3DNH
8.  GRHub Link ZS1I-L
   

Apologies:

1.   Theunis ZS2EC 
2.   Lem ZS1LEM
   

Announcements:  

The Net now has a permanent name.  A decision was taken to call it the NSN - Net  (Net Sonder Naam)   It was decided to keep the name NSN - Net.  The name does not reflect to any group or area but it represents all those who participate in the weekly Net.

Thank you so much to all those who submitted suggestions in this regard.  

Ukrainian and Russian Conflict - Amateur Radio Affected

The following were brought to the attention of all Net participants.

•  Amateur Radio banned in Ukraine for 30 days.  - QRZNow.com + Kyiv Independant
•  Polish Radio Hams Provide E-Mail Access via Winlink - Polish Amateur Radio League
  
•  Message from Ukrainian Amateur Radio League - Anatoly UT3UY Vice President UARL
• Please keep the following frequencies clear for TRAFFIC:  3595.5 kHz USB, 14111 kKz USB, 1865 kHz USB, 3770 kHz LSB and 7110 kHz LSB. 

Our thoughts and prayers are with all those involved and also to all the Amateur Radio Operators in Poland, Russia and Ukraine.

Weekly Topic Question:

To get the ball rolling last night I posed the following question;  "Tell us how you became a radio amateur?  Wat het aanleiding gegee dat jy 'n radio amateur geword het?

This question lead to some interesting comments from all the participants.  Unfortunately I cannot provide full detail about the comments.  I would suggest you join the Net in future to find out more about the weekly topic question being discussed.  

Very Contagious Virus:

A very contagious virus is spreading fast in the Garden Route Area.  Indications are that wearing a mask or sanitizing you hands do not protect you  from getting infected.  

Audio file played.

Come listen next week what happens when you are no longer infected by this virus.

"Round Robin/Rondomtalie":

Once again the Round Robin was found to be a favorite amongst radio amateurs.  The question:  What did you do in amateur radio this past week?   The following radio amateurs participated in the "Round Robin":

• Marko ZS1NEU - Antennas
• Thys ZS1TBP - VHF tests.
  
• Tjaart ZS3DR - Starter pack for Amateur Radio
• Janco ZS6LVJ -  First time that I can sit down and talk on the radio this week.
• Danie ZS3DNH - Work and Amateur Radio
  
• Johan ZS1I - I do the following: https://grhubnetwork.blogspot.com/ and  http://www.sarl.org.za/forum/topic.asp?TOPIC_ID=17401&whichpage=1 and Amateur Radio 101 Telegram Group.

Questions and Answers:

Q - Can I paint my antenna and or antenna traps with silver aluminum paint? 

A - Come and listen next week to hear the answer.

Q - What type of wire can I use to construct a 40m dipole antenna?

A -  Come and listen next week to hear the answer.

Q -  Can I log Echolink contacts as I do with RF contacts and will QSL cards be valid?

A -  You can log Echolink contacts in your log as a reference only.  It is not advisable to try and log Echolink contacts on Logbook of the World, Club Log etc.   You can also send QSL cards to the stations you contacted.  These cards will not be considered to be a valid contact for any awards.  Maybe one day VOIP contacts will be recognized as valid contacts.  Maybe somebody will establish a World Wide Log and QSL Card Service for VOIP and Digital Radio Contacts. 

Swop Shop:

1. Johan ZS1I is looking for 70cm Cavity Filters that are in a good working condition.  
2. Janco ZS6LVJ is looking for TK805 and TK8180 VHF Kenwood Radios
3. Thys  ZS1TBP has the following for disposal:  1  x Vertex VHF Radio and 1 x Kenwood TRC70 HF Radio
4. Tjaart ZS3DR is looking for an HF Linear Amplifier in  good working condition to relay bulletins.

If you interested in buying or providing any of the above contact Johan ZS1I by clicking HERE and I will put you in touch with the radio amateur.

There you have it.  A short summary of events that took place last night during the NSN - Net.  Once again a wide variety of amateur radio activities, something for everybody.  Can you provide more activities?  Please join us.  Your presence will be most welcome.  We need you expertise!!

If there is any questions you can contact me via email by clicking HERE.

All that remains is the next date for  "The NSN Net" gathering which will take place on Thursday, 3 March 2022 @ 19h30 on the GRHub Network.  Please diarize the date and time as to ensure that you can join us for another interesting Net.  A big thank you to those that reported in last night..  Highly appreciated!!

73

Johan ZS1I

Mossel Bay

 

 

GRHub Network live stream ARISS contact of students at Sussex Country Charter School for Technology Sparta, NJ, USA

Amateur Radio on the International Space Station (ARISS)  has received schedule confirmation for an ARISS radio contact with astronauts.  ARISS is the Group that puts together special amateur radio contacts between students around the globe and crew members with ham radio licenses on the International Space Station. (ISS)

The contact was live streamed by the GRHub Network as a test stream onto Echolink (ZS1I-L), AllStar (49355) and the 145.550 Mhz Simplex Link in the Mossel Bay area as scheduled for February 23, 2022 at 10:31 am EST (New Jersey).  This was a direct contact via amateur radio between students at the Sussex County Charter School for Technology, Sparta, New Jersey and Astronaut Mark Vande Hei, amateur radio callsign KG5GNP.   Students took time to ask questions.  Amateur Radio operators, using the call sign KD2YAQ operated the ham radio ground station for the contact.

You can listen to the contact by clicking HERE.   (MP3 Format)

Sussex Charter School for Technology (SCCST) is a STEM-focused, rural middle school in Sparta, NJ, serving 225 students. In preparation for this ARISS contact, through hands-on activities and class instruction, students worked with the local HAM radio club, high school, and university Physics departments to learn more about radio communications and solar influence on such communications. Members of the Sussex County Amateur Radio Club are supplying the direct contact equipment and will be conducting the ISS radio contact. New Jersey Institute of Technology (NJIT) has partnered with the school to introduce modules on space weather, solar cycles and ionospheric phenomena into their curriculum. Faculty members of NJIT’s amateur radio club, K2MFF, are founding members of HamSCI, and will lead the NJIT-SCCST collaboration and assist in the ARISS event and follow-up activities. Sussex County Technical School is their neighboring vocational/technical high school.

The following questions were asked and answered:

1. Do you have any telescopes on the ISS and, if so, how far can they see?
2. In the event of space debris, asteroids, or solar flares collisions, what are the safety protocols or systems to ensure the astronaut's/cosmonaut's safety in situations like that?
3. How do you exercise on the space station if there’s no gravity?
4. What science experiments are you working on that will have an impact on the future?
5. How do you feel about private space companies trying to make space travel open to civilians?

6. What is the best space food you’ve eaten, and do you notice any improvement in the quality of the food since the Deep Space food challenge started?
7. How often do you need to communicate with the Earth (Mission control)?
8. What would you do if the communication with Mission Control broke down and you couldn't communicate with Earth?
9. Being that you see 16 sunrises and sunsets in each day, how do you regulate your sleep schedule?
10. What steps are taken on the ISS to shield you from the pathway of the Sun's radiation?

11. How do astronauts control the robotic arm on the outside of the space station? Do you use a computer program or use a joystick like on a game controller?
12. Who put the first pieces of the International Space Station together and will any of it be reused after the mission ends?
13. How do astronauts maintain good hygiene on the ISS if there are no showers?
14. What happens if an astronaut gets a serious virus or other illness while they are on the ISS?

Amateur Radio on the International Space Station (ARISS) is a cooperative venture of international amateur radio societies and the space agencies that support the International Space Station (ISS). In the United States, sponsors are the Radio Amateur Satellite Corporation (AMSAT), the American Radio Relay League (ARRL), the ISS National Lab-Space Station Explorers, Amateur Radio Digital Communications (ARDC) and NASA’s Space communications and Navigation program. The primary goal of ARISS is to promote exploration of science, technology, engineering, the arts, and mathematics topics. ARISS does this by organizing scheduled contacts via amateur radio between crew members aboard the ISS and students. Before and during these radio contacts, students, educators, parents, and communities take part in hands-on learning activities tied to space, space technologies, and amateur radio. For more information, see www.ariss.org.

-  ARISS 

Ed.   -  The test transmission was a great success and will future space audio transmissions be streamed on the GRHub Network.  I will try to issue prior notifications of such events on the GRHub Network Blog.  So listen out for space and satellite transmissions on the GRHub Network in future!

The 2m Stacked "Dip-Yag" Antenna Project

Photo: Dip-Yag Antenna (Bottom view)

During December 2002 I worked up the design for this antenna purely by co-incidence. I needed two stainless steel self-tapping screws and my eye fell on the 3 element Yagi that I constructed for 2m operation. This “odd” measurement Yagi with stainless steel self-tapping screws were mounted on a mast 4m high from the ground. I unscrew and remove both the reflector and director elements in order to obtain the said screws. The driven element and funny looking boom were left intact on the mast. Later that evening I decided to contact Francois ZS1Q in George. I was greeted with the following remark ”Wat het jy nou aangevang? Jy blaas my uit die hok uit. Wat se versterker gebruik jy? “

I only then realized that I was using this “funny looking” Yagi. Tests were conducted and this led to the constructing of the odd measurement ”DIP-YAG” antenna. In amateur circles the “DIP-YAG” will rightfully be called a 2 Meter Dipole Antenna. Or will it? Be as it may this antenna give excellent results and is cheap and easy to construct.

To construct the antenna we first drill the hole for the element through the boom.  Push the element through the hole and affix the element with a self tapping screw exactly in the center of the element.  You will now have a T-shape antenna.  Fit 2 X 10mm Plastic end caps to each opening of the element and 1 X 20mm plastic end cap to one end of the boom. The SO239 connector is affixed to a piece of aluminum plate bent in a “L” shape.  A hole is drilled at the short end of the “L” through the plate, the SO239 is fastened with 4 X 8mm bolts and nuts.  The long end of the plate  is fastened to the boom with a rived-gun,  approx. 80mm away from the element.

Photo: Showing the Gamma Match of the Dip-Yag Antenna


The gamma match consists of a 150mm length of 10mm aluminum tubing. The 200mm piece of RG213 co-axial center (the outer cover and braid is removed) is slipped inside this tubing which telescopes into the aluminum tubing. One end is then soldered to the connector. Sliding the RG213 center in and out of the tubing tunes the gamma match. Take the 60mm aluminum tube and drill two 10mm holes 25mm appart through this piece of tube. Fit the 2 x self-tapping screws on the side of this tube. These screws act as a “lock-nut” to tighten the element and the gamma match for the best SWR. Affix the boom with a mounting bracket to the mast. Note: The best SWR is obtained by moving this matching stub up and down, as well as the sliding of the RG213 center core in and out of the 150mm piece of tubing. After obtaining a 1: 1 SWR tighten all screws and affix the co-ax cable to the boom and mast with cable ties. One 10mm- and 20mm plastic end cap is affixed to the other end of the boom and to the end of the gamma match. Seal all holes and openings with an appropriate water tight sealer.

One of these “Dip-Yag” antennas works fine for a basic, slightly off center, omni-directional antenna. The angle of radiation is lower than that of a ground plane so it does tend to work better (I guess 3 db in the favored direction). You can use more than one by stacking them vertically. Losses might make it undesirable to stack more than 2 or 4. I am currently using a two stack arrangement with the following phasing harness measurements.

PHASING HARNESS:

2 X 1.36m 50 ohm RG58 co-ax cable
2 X 386mm 75 ohm Good TV co-ax cable

The 50 ohm and 75 ohm cable is joined together for each “Dip-Yag”. The 50 ohm length is affixed to the antenna while the 75 ohm section on the other side is affixed to a ”T” piece connector. A identical harness is made for the second antenna. A 50 ohm feed line is connected to the ”T” piece and fed to the 2m radio. Note the distance I used between the two antennas is 2 meters.

PARTS NEEDED:

3m x RG58U Coax Cable
1.2m x 75 Ohm TV Cable
6 x PL259 Connectors
1 x "T" Connector that except PL259 connectors.
15m x RG58, LMR400 or RG213 Coax Cable

IMPORTANT NOTE:
Always use good quality connectors and cable to curb excessive losses.  Bad connectors and cables will give bad results.
Seal all connectors and joints with a good quality sealer.

This antenna is quite broad-banded and performs well during static buildup in the summer months.  Thanks to Nico ZS2N for the his MFJ Analizer and for the constructing of the phasing harness during his visit to Mossel Bay in April 2003.

I have done extensive tests with this antenna and has subsequently got rid of a Ground Plane Antenna, J-Pole and Slim-Jim.  Construct this antenna and you will see why. If you build one of these antennas I'd love to hear from you and see pictures of your work.

Finally I would like to thank all Radio Amateurs for their input and help with initial tests.  Without this help the project would not have been possible.

Photo:  Co-phased Dip-Yag's on the mast.

ADDITIONAL NOTES 6 JUNE 2008:

As a result of several e-mails received I decided to post new photos and more information including a diagram of the phasing harness.

This antenna gave very good results.  This antenna was used for 2 Meter Simplex Communications with the one Dip-Yag antenna facing towards Hartenbos and the other in the direction of the greater Mossel Bay, George and Sedgefield area.  The top antenna facing towards Hartenbos had the task of getting in behind a hill where one of my good friends stayed at the time.  The J-Pole and Slim Jim used previously could not deliver the goods.  The Dip-Yag did and excellent job in delivering what was expected from it.   A Yagi would possibly have done the job, but then the George radio amateurs could not hear me and I could not hear them.  The stacked Dip-Yag solved the problem and we could continue with our nightly 2M Simplex Nets.  This antenna construction could also be used for a repeater.  By stacking 4 of these "Dip-Yag's" your repeater could have a reasonable coverage area.  A plus would be the cost to construct a 4 stack "Dip-Yag" antenna.

What about feed-line and connector losses?  I used RG58 and a good quality 75 Ohm TV line for the phasing harness and still received 5.9+10 reports from Hartenbos and George.  Use the best connectors and coax you have.  If you use other cable that RG58 and 75 Ohm TV line then you have to re-calculate the length of cables as the velocity factor of cable differ.  However the use of RG213, LMR400 and RG58 for the cable going to the radio need not be re-calculated.  The following formula can be used for the re-calculation of the 50 and 75 Ohm cables:

(234/145(Freq.)) x 12 = 19.23 inches
19.23 inches x (Velocity Factor) =  (Inches)  x 25.4 = (Millimeters/Length of cable)

I trust that the new information provided will be of further assistance to those currently busy constructing this very useful antenna.  A single Dip-Yag is also very portable and could be installed and used for emergency communications.   I  have one in my  "Ready to go bag"!!

The weekly NSN - Net #3 is taking place this Thursday, 24 February 2022 @ 19h30

 

THE WEEKLY NSN NET:

The "Net Sonder Naam" Net meets every Thursday evenings at 7.30PM SAST and typically runs around hour and a half in length depending on how large the net is and how many topics there are for discussion.  This Net is not a Club activity!!  It is constituted by interested radio amateurs in South Africa and even Worldwide.

ABOUT THE NET: 

The preferred languages will be English and Afrikaans.  You use the language of your preference. The net provides a forum for participants to discuss amateur radio topics, ask amateur radio related questions, and to receive advice, information, and guidance from the pool of knowledge and experience of the net participants. The net is open to all amateurs worldwide and we encourage your participation. We hope you have a little time on Thursday evenings to report in and say hello. 

ORDER OF THE NET: 

The following is the order of segments of the NSN - Net : Rapport in, Welcoming, Apologies, Announcements, Radio amateurs new to the Net, Weekly topics, "Rondomtalie"/Round robin, Questions and Answers, Swap & Shop listings and Late rapport in's, Date and time of next NSN - Net, Closure.

WEEKLY TOPICS:

Every week we choose a topic question and ask it to each participant. If you have an amateur radio related topic or survey question that you'd like the net participants to discuss, we'd love to get your suggestions and input. Please email your topic suggestions by clicking HERE. If you prefer that your name/call not be used when we pose your topic to the net, please state so in your email and we'd be glad to respect your privacy. 

QUESTIONS:

If you have an amateur radio related question or technical issue that you'd like advice, answers, or guidance, you can ask it during the Q&A portion of the net, or you can email it to me in advance and I will ask the question/s to the net on your behalf. Someone on the net probably has an answer for you. If you would like to submit a question to the net, please email by clicking HERE  Also, if you prefer that your name/call not be used when we ask your question on the air, please state so in your email.

SWAP AND SHOP:

The purpose of the "Swap-Shop Portion" of the NSN - Net is to list amateur radio related items for sale/trade/want. The NSN - Net assumes no responsibility or liability for any transactions, items sold or purchased. Everyone is welcome to email items for sale/swap by clicking HERE. 

NET LOG:

A net log (participated stations and log in's) will be available after the Net has closed. If you would like a copy of the log send me an email by clicking HERE 

FEEDBACK NSN NET: 

Every week I will post feedback on what happened on the NSN Net. The posting will be available on the GRHub Network Blog and Amateur Radio 101 Telegram Group. I will only provide a short overview. If you would like to know more then I suggest you join the weekly Net.

JOINING THE NET: 

You can access the Net as follow:

• Echolink - Connect to ZS1I-L

• AllStar - Connect to node 49355

• VHF - 145.550 Mhz Simplex in the Mossel Bay area.  Remember the 88.5 khz CTCSS tone

• Any other Echolink, AllStar repeater or link station that is connected to either ZS1I-L or node 49355

• Use of your cellphone by installing Echolink on your phone

• By means of a Network Radio example Enrico TM8 etc.

FINALLY:

Please feel free to join us tomorrow evening at 19h30 SAST.  We are all looking forward to you company and inputs in this regard.  Please also tell your amateur radio friends about the Net. Get rid of that daily stress and enjoy a good hour or two in the company of amateur radio friends.

Hope to hear you tomorrow night at 19h30 SAST on the GRHub Network!!

Foolproof Power Backup Controller Project for your Radio, Radio Link or Repeater (Part 2)

Updated:  23 Feb 2022 10h35 SAST  - I was asked to publish an outlay of components.  Now here is the article, diagram and hand-drawn outlay.

 

Click on images for larger view.

Part 1 of this article available HERE

In Part 1 I described the controller and tested it on the workbench.  In this posting I will display images of the project build and the completed controller that was build into a cabinet.  I tested the unit and it is working great.  Uninterrupted operation is realized even in the event of a commercial power outage, without the radio "dropping out" at all. This circuit is now used on the 145.550 Mhz RF Link Radio of the GRHub Network. No manual switching from power supply to battery and from battery to power supply.  As indicated before this unit has many other uses.  Can you think of any? 

Finally:  This unit can only be used for 12 - 24 DC batteries and power supplies.  It is really simple to construct but do what must be done,  switching between power supply and battery in the event of a power outage.  I am considering to add a low voltage battery circuit to the unit to warn me should the level of the battery fall below the set voltage for gel-type batteries.  This will prevent any damage to the battery.  I just decided to install the low voltage battery unit as per photo.  Found one in my module box.  Was this a worthwhile project?  By all means, yes.  I actually need 3 of these units.  Who knows I might just build two high power/current units in future.

DIY Helical Antenna 5.8GHz (10 Turn): Mossel Bay Mesh Network

Here is my version of the 10 turn 5.8Ghz Helical Antenna described by Andrew McNeil

Link: https://www.instructables.com/Helical-Antenna-58GHz-10-Turn/

This antenna is currently installed on the ZS1I-5 Mesh Node and pointing towards the ZS2I-1 Mesh Node.  This antenna is very directional but work extremely well.  Up to now this antenna has proven itself and till today no connectivity losses occurred even in rainy weather. Approx cost of this antenna = R100 bucks as I had many of the required parts in my junkbox.  Thanks must go to
Andrew MCneil for his guidence and well explained tutorial for this antenna.

Bad audio quality on Echolink. Do something about it!!

I recently received a Telegram message from Curtis ZS6CMO informing me that my audio on Echolink and AllStar was scratchy and not my normal "pleasant" audio that he is used to.  Well I get very agitated with somebody telling me my audio is bad.  Do you also get upset?  No, just joking.  I appreciate the message from Curtis immensely.  If you are not told that your transmit audio is poor or bad then how will you know it.  Listening to bad audio quickly make me QSY to another station or frequency.  In the olden days your were quickly told that your audio is bad and not acceptable.  Do something about it!!  I am old school and believe that your audio must at all times be acceptable and pleasant to listen to.  Unfortunately I cannot change my voice the good Father gave me but I can do something about bad audio.  I decided to investigate and explore why the audio was scratchy as I did not alter any settings of the network or radio.

Now where do one start? Here is a few pointers to look at:

• Power Supply functionality.  Does you power supply provide the correct voltage and amps.
• Power Supply interference.  Check EMI and EMC.  (EMC =  “ability of equipment or a system to function satisfactorily in its electromagnetic environment without introducing intolerable electromagnetic disturbances to anything in that environment”. This phrase can be simplified to ‘tolerate outside disturbances and do not disturb the outside world’.  EMI = “degradation in the performance of equipment or transmission channel or a system caused by an electromagnetic disturbance”. This phrase defining EMI can be simplified to ‘degradation in performance due to outside disturbances’.
• Noise over the Ethernet coming from switches, hubs, routers, raspberry pi's etc.
• Cooling Fans.  Noise generated by cooling fans or their circuitry.
• Internet noise aka WiFi Interference. 
• Bad audio from Echolink or AllStar servers
  
• Microphone issues like bad connection, to close to monitor speakers, bad microphone, incompatibility with PC Soundcard etc.
• Bad Internet connection
• RAM of Raspberry Pi getting full  
• Failure to reboot computers and router to reset connections
• Interference from outside my QTH
• Interference from household equipment in the home
• Pre-failure of equipment or dry joints
  

Now this is quite a comprehensive list but before you say I will not use Echolink or AllStar as there could be  more issues that normal RF Radios, I want to assure you that this is not the case.  I took a  shortcut because I know that if the system has been up and running for some time it needs to be rebooted.  This include every item connected to the network or a radio.  This will sometimes solve a few hick-ups that might be present.  This morning a did a complete shutdown of the network and then restarted everything. After starting up the network the audio issue was solved and the "pleasant" audio was back again.  But not for long.  After a while it was back. This time around the audio had a buzzing sound and there was no RX.  I did some fault finding and found that the USB Soundcard was the culprit. I replaced the unit and low and behold the "pleasant" audio was back.  I will later look at the faulty soundcard.  At this stage a suspect a dry joint could be the problem.

So I do not have the perfect audio in Echolink or Allstar but I try to provide good audio as far as possible.  I think you will agree that many of the above mentioned pointers could occur and cause problems and therefore I listed them here.  Hopefully this can help others that do experience problems in this regard.

Just goes to show my audio on Echolink can also be bad and unacceptable.

Homebrew: 16 Element DK7ZB 70cm Yagi Antenna

 

Top: DK7ZB 70 cm Antenna constructed by ZS1I
(Apologies for the quality of the outside photos as it was very foggy when these were taken.)

The antenna describe here is a 70 cm DK7ZB - Design antenna. Constructing this antenna is straight forward, to the point and you should not have any problems if you stick to the basic rules of antenna construction. This antenna is a 16 element closed-spaced 70 centimeter beam. It features high forward gain good pattern and acceptable bandwidth. It has a excellent front to back ratio and is especially suited for DX contacts where maximum gain and narrow beam width is required.

The feed point impedance for this yagi is 28 Ohm, the radiator is a simple split dipole with the DK7ZB-match.  The yagi have insulated mounted elements above the boom.  This is the best way for mounting, because the formulas for mounting through the boom and on the boom are not very trustworthy.

I prefer elements with 8mm or 10mm diameter, because they are much less critical than smaller diameter.  Bandwidth and tolerance against rain, fog and stacking harnesses are much better with thicker elements.  The elements are mounted insulated with insulators  I made on the milling machine.  The screw fixing the element to the boom has no influence to the length of the element  as it is in the electrical "zero - point" and is connected to the boom.

Specs:

High-gain, high front to back ratio. Freq. 430 - 435Mhz
Boom 3.88m
Gain 15.5 dBd  F/B > 40dB (!)

Top:  Completed Antenna (Note: Some of the elements must be re-aligned and tightened after they were accidentally bumped while testing the antenna.)

Top: 16 element Yagi for 70cm

Top:  Driven Element, Match and other elements.

Top: PVC holder for match and driven elements

Top: Driven elements fitted with insulator visible.

Top: DK7ZB Match

Top: Completed driven element.

Top: Closeup of the DK7ZB Match
(Click on images for larger view.)

OK time for and update:

Construction info can be found by clicking HERE

Many thanks to DK7ZB for making yagi construction information available to all radio amateurs!

ZS1I notes on the construction of the above antenna:

All the construction material were available at a local emporium.  I had 99% of the material in my garage and decided to build a 16 element 70 cm DK77ZB Yagi. As the elements have to be isolated from the boom I had to mill my own insulators.  The milling of the insulators took time and 15 isolators were milled over a period of two days.  Construction is straight forward and to the point.  The assembling of the driver element also took time as I wanted it to fit snugly into the  PVC electrical box.  The parallel 75 Ohm cables calculations for the DK7ZB Match came to 11.5 cm using RG59.  I used a good quality RG59 which was very hard to bend and fit into the PVC box.  I managed to fit it snugly  with very little extra space left in the box.

Once every element was fitted it was time to test the SWR.  I do not have the luxury of a MFJ antenna antenna analyzer so all SWR tests and measurements were conducted with a small but effective Nissei SWR Power Meter.  I used this meter in many projects before and when tested afterwards with an MFJ antenna analyzer it confirmed all the readings as before.  The fist test was 1m above ground and it reflected an SWR reading of 1.2 on 433.895 Mhz.  I decided not to trim the driver elements and pushed the antenna up to  about 9m above ground.  SWR:  1.1 on 435 Mhz.  Good enough for me.

Now for the real test.  Willie ZS2CC obliged and we tested the antenna on air for nearly an hour.  Different antennas for reception and different power levels.  Distance 40km.  Although the distance is very short, the antenna performed as expected.  5/9 + 20 on any external antenna at 1 watt power output level.  ZS2CC even received the signal on a rubber duck antenna at his QTH.  I am quite happy with the performance of the antenna and will in future test it over longer distances.  Hope to use this antenna in future VHF/UHF contests.

That's it.  A very effective antenna at a reasonable price tag.  After all I experienced great satisfaction in homebrewing this antenna in my backyard.  Now why don't you join in on the fun and construct this antenna?