Monday, 1 October 2018

Pasir Ris Park - Ham Radio Camping Adventure

Campsite 1 @ Pasir Ris Park
Long overdue on my ham radio to-do list is to go on a camping adventure while operating a portable off-the-grid ham radio station. The challenge is to operate the station without relying on any mains electrical supply. The setup has to be practically light and portable for ease of deployment. Operating off-the-grid will sharpen your skills as a ham radio operator in emergency and disaster preparedness, keeping amateur radio on when the grid is gone.

Roughly a week ago, we applied for a camping permit using one of the AXS station near our HDB block. Then, we went shopping at Decathlon for essential camping gears. The Deer Creek Monsoon 4-man tent was bought in Malaysia and every other thing was from Decathlon. Okay, first thing first when arriving at the campsite is to establish a shelter and that is to erect the tent. The camping mallet (which I contemplated to buy at first) made driving stakes into ground an easy task.

With help from the XYL (wife in ham radio terminology), the shelter is up. Next, I will work on the antenna section. The rubber mallet did not help much driving the antenna's stake into hard ground, furthermore there was many roots beneath the grass patch. I looked around and found another sandy patch, using body weight as driving force the stake went right into the ground. Ribbon cables beneath the antenna feed section serves as counterpoises or also loosely known as 'ground'.

The antenna was set up close to the shoreline near seawater. I supposed ground conductivity is excellent giving the vertical antenna a low take off angle, perfect for reaching out to far away DX stations. Ideally, you could attach a piece of ground wire and dip the other end into salty seawater to enhance the vertical antenna's ground performance. In my setup, I should split the ribbon cables into individual wires and lay them evenly on the ground but it will look like a bunch of private hair scattered on the ground, no thanks.

Beautiful Seaview by the Campsite

Before going on HF, I operated 2m band for a short while. I removed the PAC-12 antenna feed section and attached the black aluminium poles directly on the ground stake. Then I attached the tee section with two telescopic whips and configured it into a J-pole antenna. To be a responsible ham and for the safety of other park users, the antenna was supported by 3 guy ropes anchored into the ground as risk control measure. Hence, likelihood of the antenna collapsing has been reduced to nil.

Black Aluminium Poles as J-Pole Support

The J-pole configuration tunes pretty easily. The long section is connected to the center conductor and the short section is connected to the coax shield. First, the long section's length is adjusted for lowest SWR. Then you may further fine tune for best SWR by varying the length of the shorter section. As you can see from the MFJ-259 antenna analyser below, a perfect match was achievable.

Unfortunately I couldn't reach any local stations on 2m simplex, not even SARTS 2m repeater. However, I was able to access MARTS national link through their Gunung Pulai repeater. After making contact with two 9V1 stations, I prepare the station for HF. I wish to showcase (uniHAM) UNI-715 portable CW paddle made specially for FT-817/818 series. If you glue a few strong magnets at the bottom, you could also use it with any other portable radio. It does not have the premium feel of Begali but it's cheap and gets the job done, period. My only complain is that a tool is required to attach and detach the key. A magnetic attachment would be great!

Portable Station Setup
2. MX-P50M HF Amplifier
3. LiPO Battery Pack x2
4. Tigertronics SignaLink USB
5. SOTAbeams Speech Compressor
6. uniHAM UNI-715 CW Paddle
7. Portable Fan for Amplifier cooling
8. Lenovo Miix 320 Laptop
9. MFJ-259B Antenna Analyser
10. PAC-12 Portable Vertical Antenna Kit

Chicken Rice for Lunch Break
Short Break zzz..
PAC-12 Portable HF Antenna

I worked a handful of cw stations. Furtherest was a station from Russia. Despite having difficulty receiving my signal, he kept returning my call and eventually the contact was successfully logged. As a matter of fact, I enjoyed every DX contact made using cw mode and the satisfaction was incomprehensible. It felt as if work was actually done to make each contact a success. I was calling CQ at a much lower speed, 16wpm and it felt warm at heart when stations return the call with the same slow speed just so you could understand. Such enjoyment was missing on voice and digital modes.

When the tide went out, I felt a drop in antenna performance. My calls no longer appear on reverse beacon network. Perhaps the seawater played an important role in reflecting radio waves. Took a break for shower and dinner before jumping over to FT8. As the seawater returns, the band got lively once again. Canada and USA came in strong on the waterfall. Europe was missing on the waterfall for some reasons not known to me but no complains as I logged a few US station one after another. Admittedly, FT8 is still the go-to mode when it comes to working weak signals during the bottom pit of a 11-year solar cycle.

Shortly an hour past midnight, I decided to call it a day and close down the station. Woke up the next morning before sunrise, took a shower and begun tearing down the tent. It was fun operating off the grid and I certainly enjoyed every moment at the campsite. Perhaps, my next objective is to give the low-bands a try.

Block Diagram for Nerds

Related Articles: Field Day - Woodlands Waterfront

Wednesday, 22 August 2018

470km QSO from Singapore to Perak with 5W Handheld!

The intention of this post is to demonstrate the accessibility of MARTS national linking repeater network from Singapore. The link has been broken for many years when the repeater in Ledang was experiencing some technical issues. 9M2RGP-L in Pulai was functioning, however due to the broken link it was working solo. Kudos to MARTS and its team in bringing back the glory days of the linking system. In addition, MARTS swapped the operating frequency between the linked and local repeaters. By doing so, 9M2RGP-L is now accessible to Singapore hams as the operating frequency is within the 144-146MHz band plan. Due to 9M2RGP-L high elevation, this is an easy repeater to work with from most part of Singapore.

YAESU VX-6R + 5/8 Telescopic Antenna
LiPO 12,000mAh Backup Battery
You shouldn't rely on a short little rubber ducky antenna to trigger the repeater from a handheld with 5W. Unless you're at the peak of a hill or on top of a building, you should at least pair your handheld with a decent antenna. Here, I've used a 5/8 length telescopic antenna. You can also use a magnetic base mount with a high gain mobile antenna to get the signal out whichever is convenient. To ensure a stable transmit output, I put my handheld on 'life support' with an external back up battery as the internal battery has already deteriorated.

View from the portable location, North facing
Testing from ground zero
From the Esplanade roof terrace, I managed to make contact with 9W2NBJ 470km away in Perak and 9M2CQC in Subang Jaya, Selangor. To put this into context, you would have to drive for 6 hours in order to arrive in Perak from Singapore. The contact was made possible through a series of linked repeaters along the peninsular of Malaysia without incurring any telco charges. For curiosity sake, I moved down to ground level and tried to make a contact. To my surprise, 9V1WO in Woodlands told me that I'm still holding the repeater. For more information about MARTS national linking network, visit MARTS official website.

5W APRS RF Beacon iGated in Ulu Tiram, 36km away
Distance to 9M2RGP-L from portable location, 48km away

A YouTube video of the contact made through 9M2RGP-L, Gunung Pulai.

Sunday, 5 August 2018

Reminiscences of a Singapore Ham by Joseph Seah, 9V1NQ

1945 saw the end of World War Two and for many in Singapore there was a keen sense of having to catch up with lost time and on the momentous events around the world. There was no television then and radio newspapers were the only means of bringing the world closer to us.

It was interesting to scan the radio bands for broadcast stations to listen to opinions and the music of many lands. It was this constant scanning of the radio bands which was to lead me to amateur radio.

In those days the majority of the transmission and radio traffic were either in CW or on AM. This meant that the average person could listen to special transmissions on an ordinary radio receiver as there was no need to beat the signal received with a special oscillator, which is required for single side band transmission.

It was with this advantage that I could stay tuned in to a number of AM stations which were in apparent conversation in a two-way link. But they were not in plain language! They were talking in English but the conversations were usually interspered with some strange code. The more I listened, the more intrigued I became.

Who were these people who appeared frequently on the band with CQ calls and chats about QRMs and QTHs? Yes indeed there was a pattern as many terms began with the letter Q. Ever so often I heard QSO, QRX, QSY, QRS, and invariably it was 73's and see you again.

My curiousity was aroused. They appeared a friendly lot. Surely there must be some sort of organisation behind the transmission of the link-ups for this kind of friendly exchange I thought.

It was when I tuned in to the 40m band one Sunday and heard obviously LOCAL voices having a chat in a similar fashion and the mention of a street name that gave me the final push.

Together with a friend, I was determined to get to the bottom of all this. With a portable radio working off the battery of our car and attached to a sort of lashed-up-direction-finding aerial and a sensitive field strength meter, we made a bee-line for the road mentioned in the conversation.

There were many houses on that road. So we took a chance and knocked on the door of a house which has a rather strange square antenna atop roof. We had struck the jackpot! The kindly gentleman gave us all the information to get us started. Information which was to lead us eventually to getting our passport to the fascinating world of amateur radio: our licence.

Obtaining and maintaining radio receivers in those days was quite a challenge. Test instruments and electronic components were in short supply. Transistors were unheard of. We had to use whatever substitutes that were available. And this meant scouting around in shops selling army surplus or using our own ingenuity. But messing about with a radio receiver's 'innards' was to me a fascination and a challenge.

And how do I feel after so many years spent in this scientific hobby? As must be true of any other radio amateur, I have made many friends all over the world, acquired useful electronic knowledge and a pretty good knowledge of geography. Such strange-sounding places as Crozet Island, Ulan Bator, Tuvula, are among the many places all over the world where there are radio amateurs reaching out.

All these many interesting and good people are bound together by the pursuit of a common interest. We are linked in a brotherhood which directly promotes a great deal of international goodwill. As all of us know, whatever the man's political persuasion, a radio amateur can find time to talk to a grandmother, a hospital patient, a king or a baker. Race, creed, colour, status, and all those other barriers to a more friendly world are non-existent among radio amateurs.

One of the results of this goodwill was the feeling generated among ASEAN amateurs that we should meet regularly for eyeball QSOs. Hence the origin of the SEANET conventions. And what better testimony to the ability of amateur radio to foster goodwill than that the fact that those coming to SEANET conventions are no longer confined to the South-east Asian region but from other parts of the world too!

Reference: SEANET '78 Singapore, 10 - 12 November.
8th SEANET Convention, Singapore as host for the second time.

Sunday, 1 July 2018

YAESU FT-818ND - 500Hz CW Filter

YAESU YF-122C - 500 Hz - Collins Mechanical Filter
Many modern HF transceivers are fitted with roofing filters to help cope with unwanted strong adjacent signals on a crowded HF band. By activating a narrow roofing filter, you will be limiting the passband bandwidth thus rejecting strong signals outside the filter's range. This will allow you to effectively pick out an incoming weak signal without the strong signals overloading your receiver. 2800 Hz - 1800 Hz are common for SSB signals while 500 Hz - 125 Hz are used mainly for CW signals. It is a pity that FT-818ND which is the so called updated version of FT-817ND does not come with any roofing filters pre-installed. Even Chinese made XIEGUs have built in IF roofing filters! Fortunately, I had one YF-122C lying around which I took out from my previously owned FT-897D.

Loosen the bottom screw
Installing the optional roofing filter in the FT-818ND is literally plug-and-play. There is only one slot available so choose which filter to install wisely. I'd recommend the 500Hz filter if you use CW often. First, you have to remove all the screws on the top panel. I recommend removing the top screw on the neck strap bracket and loosening the bottom screw. This will allow you to remove the top cover panel easily.

YAESU FT-818ND Internal Parts
Be gentle when lifting up the top cover as you do not want to accidentally break the loudspeaker wire. I would leave the speaker wire connected as the process does not take long. At the bottom right, close to the front display panel, you will see a slot marked 'Filter Unit'. That will be the slot for the additional roofing filter. Above this slot, is the factory installed muRata CFJ455K-14 SSB ceramic filter. Sitting on the last row are ceramic filters for FM/AM. These bastards tend to fail prematurely if DC blocking capacitor was not installed in line with the filters. 

Optional Filter Unit Slot
The filter unit installation is fool proof. It is 3 pin on one end and 4 pin on the other to make sure the filter is installed correctly. Just make sure to insert the filter into the slot with the filter unit facing up and you're good to go. Before putting the top cover back on, you may want to quickly test if the filter is installed correctly. Turn on the radio and enter menu item #38 (OP Filter). Choose the correct filter setting, CW / SSB. This function will tell the radio that an optional filter has been installed.

To turn on the optional filter, navigate to operating function row 7 [IPO,ATT,NAR]. Press C (NAR) key to activate the filter. To turn it off, just press C (NAR) again. You should be able to hear a difference in received noise.

Optional Filter Installed

Flat Screw vs. Cone Screw
When replacing the top cover, note that there are two types of screw involved. Pay attention to the shape of the screw hole to determine which screw to use, either the flat or cone screw.

Neck Strap Bracket - Cone Screw

Top Cover - Flat Screw
The following page is extracted from the user manual page-68 for easy reference. Enjoy your newly installed roofing filter.

FT-818ND User Manual - Page 68

Sunday, 27 May 2018

Field Day - Woodlands Waterfront

PAC-12 Vertical Whip Antenna
Woodlands Waterfront
If you're looking for an unobstructed Northern DX window in Singapore, you should pay Woodlands Waterfront park a visit. It has plenty of lush green fields with strategically placed rest shelters along the park trail. Common amenities such as washrooms, drinking fountain, vending machine and a restaurant is readily accessible. Situated along the coastal zone, soil conductivity should be great for vertical antennas. From Woodlands MRT station, you can use SMRT bus service 856 and alight at Bef W'lnds Waterfront Pk.

Yaesu FT-818ND - My new favourite!
Portable Station
At first I erected the PAC-12 vertical whip antenna, also known as a ham stick or buddistick. Using an extended version of the telescopic element which is about 5.6m long, loading coil is no longer required from 20m band upwards. Such antenna is a 1/4 wavelength long vertical, so an effective ground system is crucial for radiation efficiency. For non-hams reading this, don't panic as the 'radiation' mentioned won't turn you into X-man. As a matter of fact you're exposed to the same radiation everyday, your mobile phone. I find the PAC-12 much easier to deploy compared to the JPC-7 portable dipole system. With the JPC-7, I had to lug around a heavy light stand to support the antenna. On the contrary, the PAC-12 is self supporting by the ground stake. As I gain more experience operating portable, I will also appreciate every kg shed off my payload. In addition, the PAC-12 provides a much lower take off angle, more suited for long distance DX.

Yaesu FT-818ND Portable Radio
Yaesu FT-818ND
If you have been following my previous blog posts, you may notice my new fond for the Yaesu FT-818 radio. Although QSOs rate are miserably low, I find myself stepping into a whole new chapter of ham radio. Noise floor are naturally much lower with lesser QRMs to fight with at the field. Admittedly, I had to slap my past self in the face for saying QRP is just a matter of turning down the power knob. I was immature back then, period. I did not make any DX contact but I was able to receive a few Japanese and Chinese station with strong incoming signals on 20m. Every so often, I will send a few CQ calls on CW and see if I'm reaching out on the Reverse Beacon Network.

HAM Radio Field Day - SSB / CW
The station was closed down when it started to drizzle, a heavy downpour followed shortly. During this field day, I figured I needed a smaller lighter portable paddle for the station. Considering a Chinese copy lightweight paddle made for the 817/818 but the mounting screw is a huge disadvantage for me. A magnetic base mount will make it a no brainer. Any other recommendations? Till then, best 73's to all monitoring stations.

Disclaimer - Embracing the kiasu (scared lose), kiasi (scared die) nature henceforth this disclaimer is in place. No trees, no grass, no soil and no living organism was harmed during this amateur radio portable station setup. Tender, loving, care for the nature (and the public) has been observed as not to cause any permanent damage to the environment. Amateur radio operation is embraced worldwide, especially in developed countries like the USA and Japan.

Saturday, 26 May 2018

47th Floor Roof Garden - SkyVille @ Dawson

Sky View - North West Direction

Sky View - North East Direction
SkyVille @ Dawson
In search of great places for portable ham radio operation in Singapore, we stumbled upon another high floor roof garden nested atop SkyVille @ Dawson. Alight at Queenstown MRT station and the building is just a 5mins walk away. Access to the 47th floor roof garden is free for all, 24/7. There are tables and benches provided for your convenience but however most of them are rather dirty, some wet wipes will take care of that. Favourably, you get a 360-degree sky view and Indonesia is certainly in line of sight.

Do note that the elevator motor is in close proximity and may cause a high noise floor or introduce some QRM to the receiver. We did note a drop in receiving performance on VHF. Occasionally, the squelch will be opened by QRM.

VHF J-Pole Configuration

VHF L-Pole Configuration
VHF Buddipole
With the help of an antenna analyser, the Buddipole can be configured into different types of combination on the VHF band. J-Pole, L-Pole, Dipole, Sloped Dipole, V-Dipole, etc. I tried calling for a station in Woodlands but it couldn't receive my signal, signal report was faint. Possibly due to my excessively long coax cable, 17m that is! Big no-no for QRP. I have no problem receiving him, signal report R5 S6. Then I reconfigure the antenna to L-Pole setup. The L-pole should provide some directivity. Before I could get a signal report, his radio decided to rest-in-peace. Tough luck..

Warm Up Session - VHF Testing

20m Band Loaded Dipole (Buddipole)
DXing - 20m Band
Incidentally, CQ WPX CW contest is taking place throughout the weekend. The CW portion of the band is busy with CW contest so I decided to work SSB instead. I could use the WARC band on 30m but I do not have the loading coil tapping position and didn't want to waste any time tuning due to bad WX ahead. I'd like to limit myself to CW and SSB for QRP sessions for practical reasons, while the all mighty FT8 digital mode can be done at base. Didn't take long for the first drop of rain to come and I had to pack up and go. No contacts made but that's the norm for QRP ops, I guess.

SSB Portable Operation on 20m Band

Portable Equipment for the day
It was a chore carrying the tripod on public transport, different story if I could drive around in a car. There isn't any soil up there that I could plant a stake for a vertical antenna. Wire antennas may not be feasible too. Considering the effect of height from ground with relation to a dipole's radiation pattern, I will need to further study if the buddipole at such a height will provide any significant benefit in terms of DX performance. I'm hesitant to use a tall vertical antenna configuration on the tripod for safety reasons. It may topple over and worse, attract lighting. Otherwise, for HF ops the park is the way to go!

Horizontal Dipole Height Above Ground vs. Radiation Pattern