Hardware, Software, Experiences
SARTS talk by Klaus, 9V1KG, 29th July 2021
Klaus presented his setup and experiences working linear Satellites.
From Sat, July 11, 12:00 z (20:00 SGT) to Sun, July 12, 11:59 z (19:59 SGT) the international IARU HF World Championship takes place. Details and rules are given on the ARRL website.
SARTS will participate with a IARU Member Society HQ Station under the call sign 9V1HQ. We hope to see a good participation.
If you want to renew/apply for SARTS membership from overseas and you don’t have an SGD bank account, please use the information below.
Beneficiary Bank Information (mandatory)
Bank Name: Oversea-Chinese Banking Corporation Limited
Address: 65 Chulia Street, OCBC Centre, Singapore 049513
SWIFT Code : OCBCSGSG
Beneficiary Information (mandatory)
Account Name: SARTS
Account No: 524701182001
Same as above plus:
Intermediary/Correspondent Bank Information for USD only
Bank Name: JP Morgan Chase Bank
Address: 1 Chase Manhattan Plaza, New York, NY 10015, USA
SWIFT Code: CHASUS33
Last updated: 2021-08-01
|9V1AJ||G. S. Balakrishnan|
|9V1BC||Solomon Tan Wei Jie|
|9V1BG||Achala Daarshana Senaranta|
|9V1CC||Soh Cheah Choon|
|9V1CE||Kevin W Rogers (KF7TUU)|
|9V1CK||Claus J Karthe|
|9V1CL||Daniel Deng Jue|
|9V1CS||C. S. Lim|
|9V1CV||Choong Sek Yeen|
|9V1DT||Sampath Kumar Padmanabhan|
|9V1FH||Thum Fu Hang|
|9V1JN||Jothinathan G. S. Sundram|
|9V1JT||Jose Carlos (JC) Cortez Tupaz|
|9V1KS||Tan Koh Siang|
|9V1LC||Choong Lee Song|
|9V1LW||Chia Lih Wei|
|9V1OD||Tan Lian Huat|
|9V1OG||Rene Atienza Ogie|
|9V1OW||Dr. Masahiro Wada|
|9V1PL||Philip Lai Yong Yeow|
|9V1SV||Azhaga Muthu Siva|
|9V1XK||Andy Yee Lai Seng|
|9V1YP||Chew Lip Heng|
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).
by 9V1DT, April 2021
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.
One page guide as pdf (9V1YP):
by Philip Lai, 9V1PL
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.
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.
Using a Diamond AS1430 Yagi directional antenna, I pointed it towards the repeater as good as possible. The building walls on the right would affect the radiation pattern; that would likely have a negative impact to my transmission.
Our veteran HAMs often advise us to be creative in our thoughts and design of antenna type and locations. With that in mind, I decided to try out a higher gain vertical antenna. On the same spot, I erected a Diamond NR22LH vertical. The test was a complete fail!
Now the NR22LH became one of my best antennas in the field of “Parks on the Air” (POTA).
“Poke the sky”
In the midst of my frustration, I decided to explore working on satellite. That was when 9V1KB introduced me to a group of satellite HAM led by 9V1YP.
We began hitting satellites such as LAPAN IO-86 and the ISS. By hitting I mean that I was very successful with the Automatic Packet Reporting System (APRS).
Through IO-86 and ISS, my APRS packets were received in the Philippines, Thailand and Indonesia with replies from other HAMs. This motivated me to use my yagi antenna almost every day, quoting 9V1YP “Poke the sky”!
So what happens, when the satellites are out of sight? There’s really nothing else to poke out there. This was, when I got bored cursing at those buildings in front of me. Then I started thinking about the theory. If one could bounce signals off the moon, the satellites, why not these buildings?
That gave birth to another experiment bouncing my APRS packets off these buildings.
To my surprise, the success was beyond my expectations. I actually managed to hit an APRS iGate in West Malaysia’s Batu Pahat, which got me to another station in Malacca!
Different buildings send signals to different directions
Day after day I would point my Yagi at these buildings in front of my balcony, although I must say there were fair amounts of time between successes and failures.
I began plotting these building for which direction it would send my signals. Subsequently, I decided to dive deeper into the facet of these buildings, each square or rectangular block presented a few angled surfaces to me.
I could bounce my signal backwards to the north (Remember, my balcony faces south west). I could bounce it towards the north east, and then I found the side of two of these buildings allowing me to bounce my signals to the west! Yes, that’s where I hit and held the SARTS repeater successfully.
We often look at how much power our equipment can transmit; often a very good antenna setup gets us our contacts with very little power needed. I could now trigger and hold the repeater at 0.5 W!
In conclusion, I hope this article provides an alternative to those of us facing similar challenges. I learn as a HAM to be creative, to explore within the boundaries and rules governing this hobby, and never give up since there are always many solutions to a given challenge.
9V1PL / KJ7VOT
by Solomon, 9V1BC
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?
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|
|Antenna||Icom AH4 + Random Wire|
Homemade Inverted V Dipole
|Logger||Laptop running XLog|
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.
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.
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.
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|
|K||Kilo||Kilowatt (not to be confused with kW)|
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.
|“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 ”
|“Over Over”||Me: “CQ CONTEST. 9V1BC. CONTEST”|
Him: “OVER OVER”
Me: “7C8C, 59, 060 ”
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.
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.
73 Solomon, 9V1BC
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.
|9V1BD||Single OP||20 m||Low||Rookie|
|9V1CD||Single OP||40 m||High|
|9V1HY||Single OP||20 m||Low|
Raw scores will be published in about 2 weeks. Thanks to all for your active participation!
The CW part will take place on May 29/30, 2021.