Radio signals passing through the ionosphere can be affected by small irregularities of the ionospheric plasma. This phenomenon is called radio scintillation and can strongly disturb or disrupt the signal transmission. As a result it can prevent a GPS receiver from locking on to the signal and can make it impossible to calculate a position. Less severe scintillation conditions can reduce the accuracy and the confidence of positioning results.
Transionospheric radio scintillation is statistically characterized by two parameters, amplitude and phase fluctuations indices, denoted respectively by S4 and σφ.
S4 is defined as the ratio of the standard deviation of signal intensity and the average signal intensity. Amplitude scintillations are prominent near the geomagnetic equator. They almost appear regularly in the evening hours.
σφ is defined as the standard deviation of a linearly detrended phase data segment. Phase scintillations are prominent in high latitudes, and their occurrence rate increases with geomagnetic activity.
SARTS received a request for statistics or help in acquiring statistics of ionospheric scintillation in the VHF range. VHF is not a common frequency range used in space infrastructure and there seems to be a lack of statistics in the area between tropics, where the ionosphere is bubbling quite frequently.
For interest or feedback, please comment below or contact the webmaster (9V1KG).
A short guide by Sampath how to prepare for and get the FCC license. The US FCC license is well recognized world wide and sometimes can be helpful to get a visitor’s ham radio license abroad.
This article was motivated by my fellow HAMs from the satellite group. Based on my success with the application of the concept of EME on 2 m to our SARTS Repeater without line of sight, I hope this write up can help those in the hobby with similar challenges to explore the concept of EME.
Earth-Moon-Earth communication (EME), also known as moon bounce, is a radio communications technique, which relies on the propagation of radio waves from an earth-based transmitter directed via reflection from the surface of the moon back to an earth-based receiver.
The challenge of my location (QTH)
I am located at the South Eastern Coast of Singapore, an apartment dweller with low elevation of 25 m facing south west. The distance to the Singapore VHF repeater is approximately 12 km. The small balcony with an opening of just slightly over 100 degrees is surrounded by tall buildings and makes it difficult for me to reach the repeater located at Dover.
For many months, when I first started as a new HAM, all I could hear was noise from my handheld (HT).
Each time I pushed the PTT, I couldn’t trigger the repeater, but even when I could trigger the repeater, I couldn’t hold it transmitting. It was frustrating, I fully understand, if you are facing similar challenges.
Photo of me during the contest. Taken by Amos Hoe 9V1HH.
Contest is by no means exclusive to the elite HAMs with large tower, yagis, fanciful equipment and years of experience. They do have an advantage, but we rookies have a seat at the contesting table too. On March 27th and 28th 2021, I participated in my first SSB contest. It was the CQ WPX SSB contest. It was a very fun experience, and I was extremely excited that I could have phone conversations with HAMs in places as far as Europe and North America. In this particular blog, I share my setup, experience, and the lessons I learned from this contest. I hope it might inspire you to get an amateur radio license and join us in the next contest to foster international friendship. If you already have a license, well then, what are you waiting for?
My setup for the Contest
HAMs always like to ask each other what equipment they use, and I see this question coming my way. This is my equipment list for the contest.
Power Supply
Alinco DM-330FX
Radio
Icom 718
Antenna
Icom AH4 + Random Wire Homemade Inverted V Dipole
Logger
Laptop running XLog
Contest Experience
Equipment in the trunk of my car. My radio is on the left. The antennas are on the right. The miscellaneous equipment is in the box in the middle.
I packed up my stuff into the trunk of my car. It fit nicely into a small compact compartment. I brought a few tools – like a screwdriver and a small knife – and spare items just in-case I had to make quick field repairs. This setup is almost impossible to carry by hand or public transport. After all, the Icom 718 was made to be a base station, not a mobile one. I set up my station on a nice hill in my school. It was one of the areas I identified as potentially suitable for radio operation given its decent radio horizon, and relatively less noise compared to my home.
Night time view from the hill where I operated from. Taken by Amos Hoe 9V1HH.
I set up my random wire antenna right beside the down slope. I did not want anything to block my signal. The white box is the AH-4 antenna tuner. It gives me the ability to switch bands at will. An antenna typically needs more time to be tuned and adjusted when the operator wishes to change bands. In this setup, a wire of random length is attached to the AH-4 tuner, and suspended off the ground by a fishing pole about 16′ high (5m). A ground wire is attached to the other end of the tuner and thrown down the hill. Antenna theory is very complex, especially with impedance, resonance and radiation pattern, I may have given you the false impression that I had taken them all into consideration in my setup. This was a bare minimum setup. I made no such fanciful consideration. My priority was simply to get on the air.
My random wire antenna setup, tuned by the Icom AH-4.
Unfortunately, barely half an hour after I set up, a huge storm streamed by and took away four hours of valuable contest time. What a wet blanket! The wind was so strong it bent my fishing pole a good 45°. But I wasn’t too concerned about the pole breaking. I had a spare. I almost always bring a spare antenna. I resumed the contest immediately after the rain stopped.
My point of view (literally) during most of the contest. I eventually got back pain as the radio was placed too low to the ground. I moved it later to the top of the shelf.
For almost the entirety of the contest, I either called CQ CONTEST on an empty frequency, or I tuned around on the dial to find others calling CQ CONTEST. I had my hand on the mic and the other hand on the electronic logger, XLog, on my laptop. During the first two hours of the contest, I only got contacts from Indonesia. Then I got contacts from Japan, and Australia. In the evening, I was very surprised to hear European and North American stations!
Time (UTC)
Locations Heard
0230 to 0320
Indonesia
0720 to 0920
Indonesia, Philippines, Hong Kong, China, Japan
0920 to 1030
Indonesia, Japan, Australia, China
1130 to 1300
Indonesia, Malaysia, Philippines, China
1300 to 1800
Indonesia, Philippines, Australia, United States, Ukraine, Slovenia, Serbia, Italy (but Italy could not hear me), Poland
A contest SSB QSO goes like this:
Me: “CQ CONTEST CQ CONTEST 9 VICTOR 1 BRAVO CHARLIE CONTEST” Him: “NOVEMBER DELTA 7 KILO ” Me: “NOVEMBER DELTA 7 KILO, YOURE 59, 068. QSL?” Him: “QSL QSL. YOURE 59, 1509. GOOD LUCK FOR THE CONTEST. 73” Me: “THANK YOU. YOU TOO. 73. THIS IS 9V1BC. CONTEST. QRZ?”
The key exchange in this contest is the signal report and the serial number. The serial number is particularly important as it is used to verify QSOs. In this case, ND7K’s report to me is that my signal is 59 (meaning readability of 5 out of 5, and signal strength of 9 out of 9) and that I am his 1509th contact for the contest. My report to ND7K is that his signal is 59 (meaning readability of 5 out of 5, and signal strength of 9 out of 9), and that he is my 68th contact.
Sometimes I call CQ for a good 15 minutes or so before a station even responds to me. I would tune around the band then to see if the band had died. I wouldn’t want to waste energy calling when no one can hear me. But that’s how it is even more exciting when a station finally responds! My eyes light up and I get all excited!
Sometimes, the QSO does not go as well. Here’s one example. He couldn’t hear my callsign. Maybe I was being stepped on by other stations which could not hear me. Needless to say I gave up. I’d be wasting his time and my own trying to force the QSO through the QSB.
Me: “9 VICTOR 1 BRAVO CHARLIE” Me: “9 VICTOR 1 BRAVO CHARLIE” Him: “IS THAT A KILO BRAVO?” Me:“9 VICTOR 1 BRAVO CHARLIE” Him:“9 VICTOR 1. OK OK. QSB. QSB.” Me:“9 VICTOR 1 BRAVO CHARLIE” Him: “I’M HEARING A 1 KILO BRAVO CHARLIE. AGAIN?” Me: “9 VICTOR 1 BRAVO CHARLIE” Him: “KILO 1 BRAVO CHARLIE?” Me: “NUMBER 9. VICTOR. NUMBER 1. BRAVO CHARLIE” Him: “OK. VICTOR ECHO 1 BRAVO CHARLIE. YOU’RE 59” Me: “NEGATIVE NEGATIVE. NUMBER 9. VICTOR. NUMBER 1. BRAVO CHARLIE” Him: “VICTOR ECHO 1 KILO BRAVO CHARLIE. Roger?”
It’s normal to copy the wrong callsign and serial number. Everyone has a different accent. A few stations will do the exchange in their native language. I heard a few Indonesian stations do that with other Indonesian stations. A Chinese station gave me my report in Chinese. But not everyone understands each other’s native language or heavily accented English. Thus, it is normal to hear people use other forms of phonetics to complement the NATO ones. Some examples are listed in the table below.
Letter
NATO Phonetic
HAM Lingo
Q
Quebec
Queen
U
Uniform
United
O
Oscar
Ontario
G
Golf
Germany
J
Juliett
Japan
V
Victor
Victoria
K
Kilo
Kilowatt (not to be confused with kW)
F
Foxtrot
France
For example, the callsign KJ7VOU could be phonetically spelled as “KILOWATT JAPAN 7 VICTORIA ONTARIO UNITED” instead of its NATO form, “KILO JULIETT 7 VICTOR OSCAR UNIFORM”.
Sometimes when the signal is poor, HAMs will read back what they copy to verify. This is normal because some contests penalize for wrongly copied information. Those who watch military films like Generation Kill, police documentaries like COPS, or listen to online Air Traffic Controllers would be familiar with confirmation phrases like “read back correct”, “affirmative” or “10-4”. HAMs have a similar lingo. It is called “QSL”. It means I acknowledge receipt of what you told me.
“NOVEMBER DELTA 7 KILO, YOURE 59, 068. QSL?”
“QSL QSL. ROGER THE 59, 068. YOURE 59, 1509. GOOD LUCK FOR THE CONTEST. 73”
However, like the NATO phonetics, many HAMs have their own unique way of confirming that the read back is correct. These are usually replies to the question, “IS THAT A QSL?”, which asks you to confirm whether I have copied you correctly.
Phrase
Example
“Roger Roger”
Him: “9V1BC, YOU ARE 59, 1509” Me: “059 3509. IS THAT A QSL?” Him: “NEGATIVE. NEGATIVE. 1509. 1509” Me: ”ROGER. 1509. IS THAT A QSL?” Him: “ROGER ROGER”Me: “THANK YOU. 73 ”
“QSL QSL”
Him: “9V1BC, YOURE 59, 1509” Me: “59, 1509. IS THAT A QSL?” Him: “QSL. QSL” Me: “THANK YOU. 73 ”
This contest got so addictive I decided to pass on lunch and dinner. I had some contest rations on me, so I consumed those as my “meal” instead. I would have continued the contest through the night, but my mom called me at 2am and chased me home. So too bad for me. This is a map of the QSOs I made by the time the contest ended. I logged a total of 88 contacts (pun unintended). To be brutally honest, 88 is nowhere impressive. Many other stations rack up thousands of QSOs. My 88 is not much numerically, but it is a huge morale booster for me. For many months, I complained about the terrible noise level and poor propagation on HF. It was hard to even establish a FT8 QSO, let alone a SSB one. This contest proved me wrong, and I’m happy that it did. It is possible to have SSB contact with just about anyone anywhere with a humble setup and 100W.
Map of my 88 contacts.
Acknowledgement
I would like to convey my thanks to all the HAMs who shared their invaluable experience, advice, knowledge and even gear with me to get me started in HF, especially Daniel 9V1ZV, James 9V1YC, Peter 9V1PK, Roland 9V1RT, Ben 9V1KB, Darryl 9V1DE, Emmanuel F5LIT, and Jie Feng 9V1BD, who introduced me to HAM radio back in 2018 in the first place!
It makes no sense to do HAM alone. Part of the fun comes from making, laughing at and learning from silly mistakes I make along the way. You make my HAM experience fun and meaningful, and for that, I thank you.
The CQ WPX Contest is one of the big international contests during the year. In 2021 the SSB part took place on the weekend March 27 – 28. This year we had a record in participation of Singapore hams.
Call Sign
Category
Band
Power
Overlay
9V1BC
Single OP
All
Low
Rookie
9V1BD
Single OP
20 m
Low
Rookie
9V1CD
Single OP
40 m
High
9V1DE
Single OP
All
Low
9V1KB
Single OP
All
Low
Classic
9V1KG
Single OP
All
Low
Classic
9V1HY
Single OP
20 m
Low
9V1PL
Single OP
All
Low
9V1YC
Single OP
All
High
9V1ZV
Single OP
All
Low
Singapore participation CQ WPX SSB `2021
Raw scores will be published in about 2 weeks. Thanks to all for your active participation!
We will have our SARTS Annual General Meeting (AGM) on Jan, 28th, 2021. Due to the pandemic the meeting will be held virtually via Zoom. Members already received the meeting id and passcode via email.
Nominations
The following have been nominated by the council to serve for the 2021 work year:
President : James Brooks 9V1YC
Vice President: Benjamin Koe 9V1KB
Hon. Secretary: Jeff Yeo Nai Kwang 9V1AS
Asst Secretary : Aaron Wong 9V1AW
Hon. Treasurer: Harish Pillay 9V1HP
Council Member: Roland Turner 9V1RT
Council Member: Chu Haoyuan 9V1HY
Council Member: Arnold Cabahug 9V1CD
Agenda
Confirmation of the Minutes of the 50th AGM held on 24th Sep 2020 2.
Matters Arising from the Minutes of the 50th AGM 3.
To consider and accept the Council’s Annual Report for 2020
To consider and accept the Statement of Accounts for the year ended 31 Dec 2020
Election of Council Members and Office Bearers for 2021.
Welcome address by new council members
Election of Hon. Auditor for 2021
To consider the matter of monthly meetings by Zoom until such time when eyeball meetings may be resumed.
The K-index quantifies disturbances in the horizontal component of earth’s magnetic field with an integer in the range 0–9, with 1 being calm and 5 or more indicating a geomagnetic storm. Rising K-index results in a higher noise level, mainly below 10 MHz. A high noise level on 40 m does not imply a high noise level on 20 m.
The Solar Flux Index (SFI) is an indication of the degree of ionization in the higher stratospheric regions. Higher SFI values favor good propagation conditions on the amateur radio bands 20 m and above.
A special case is the 30 m band: both, SFI and K-index can have an impact on the propagation on this band. It is actually a good band in times of the solar minimum as well as the solar maximum.
Best time to operate on HF is after a solar flare eruption. As soon as the solar storm declines, the noise on the bands decreases, combined with an increase of the maximum usable frequency MUF. This often last until sunset. Propagation conditions on 40 and 80 m in the following night could be excellent. On the following day the MUF still can be raised, good for propagation on the higher HF bands.
In addition – after a solar storm – the magnetic disturbance is often very low, a good opportunity to work on 40, 80 and 160 m with low noise.
In order to improve the coverage of our SARTS VHF repeater and sort out technical problems, it is very helpful to have a list of practical issues experienced during operation. Therefore, please help and report any problem using either this Github link, or our contact form.
Please state your call sign, the power and antenna used with the description of the issue and date/time, when it appeared.
On Sunday, 15 November SARTS will be conducting a test of a potential new VHF and UHF repeater site. We are looking for volunteers in all parts of Singapore to assist us with signal reports and two-way contacts. If you are available, please meet us on 145.550 MHz between 3:00 pm and 3:15 pm, and on 433.625 MHz from 3:15 pm – 3:30 pm local time.
To promote social distancing in the global battle against COVID-19, IMDA has granted SARTS the shared use of the special callsign 9V1STAYHOME from 6 May through 30 June 2020.
update May 6update May 6
Licensed radio amateurs in Singapore who wish to use this callsign on a shared basis please sign up at this website:
