We have successfully conducted a live demonstration of DIWATA2’s Amateur Radio Unit, showcasing the satellite’s capability to relay signals not only to and from any point in the country, but to other nearby countries as well. In this demonstration held earlier today in UP Diliman, Quezon City, an inexpensive home-brewed antenna connected to a low-cost radio transmitter was used to access the DIWATA2 satellite. Contact was established via satellite among the amateur radio operators in various location: Anthony Guiller Urbano (4I1AWN, Quezon City), Jharwin Barozzo (DV2JHA, Pangasinan), JP Almonte (4I1DIT, Quezon City), and other stations from Japan such as IjiYoshitomo (JA6PL, Japan) and JR6DI (Japan).
To listen to a complete uncut recording featuring the Japan-Philippines contact via Diwata 2 satellite (recorded by DV2JHA), click here.
There is something special about receiving a paper-QSL card (a postcard-sized document confirming a radio contact). I have received these cards from JA3FWT (Japan), for our AO-91 satellite contact on April 16, 2019. Thanks for these great-looking QSL-cards Kiyo!
Thanks JA3FWT!
For more posts about QSL cards I’ve received from fellow hams, click here.
Interested in a paper QSL-card exchange? Catch me on one of the satellites, then send me an email:
The ability to operate off-the-grid is a huge advantage when hunting satellites. Coupled with a portable antenna, this battery-operated radio setup can be easily carried to any remote DX location while requiring only very minimal prep time (5 minutes). Simply connect a satellite antenna, turn the radio on, select the pre-programmed uplink and downlink frequencies, and you are ready to make contact!
The portable satellite radio setup consists of the following:
1. Kenwood TMV71A full-duplex VHF-UHF radio with microphone
2. 12V 8AH lead-acid battery pack with volt meter
3. Sony recorder
4. Headset
5. Other accessories (not shown) such as SWR meter, patch cable, compass, flashlight, notebook, pencil, etc.
Everything fits in a small waterproof camera bag, with room to spare for some accessories.
This setup has been used recently in a satellite demo at a local hamfest. Since only 5 watts of power is needed to access the FM satellites, this setup lasts for one week of use (about 50 satellite contacts) in a single charge, perfect for DX-peditions!
Check out more photos of the go-bag below:
In my next post, I will feature the DIY split-boom antenna I use with this setup. To learn how to access satellite repeaters, head directly to Satellite Communications.
CQ satellite! I’ve conducted a live demo of a satellite QSO at District 1 Pakulo 2019, a local hamfest held in Tagaytay, Philippines on May 11, 2019. The demo showcased a satellite repeater’s capability to relay signals and enable two-way communications to any point in the Philippines, as well as nearby countries, using inexpensive ham radio equipment.
To the following stations I’ve worked with during the AO-91 pass: JS6DRQ, DU6DKL, DU2XXA, DU4PGS, 7J1ADJ/JR6, and JA6PL—you are all 5-9, thanks for the contact, 73!
To learn how to access satellite repeaters, click here.
DIY Satellite Antenna. To view larger, click here.
My satellite antenna is a Moxon-Yagi-Uda dual band VHF-UHF antenna with a single feed point (connects directly to the radio, no duplexer needed), based on the original design of LY3LP. This allows using a full duplex radio to simultaneously transmit in one band and receive in the other. Properly tuned, this antenna has an SWR (Standing Wave Ratio) of 1.0:1 in VHF and 1.1:1 in UHF.
The antenna’s boom may be split in the middle, for easy storage and transport.
Features
1. Very good RX and TX signals. Check out the logs on my QRZ page or hear the audio recording as received by this antenna in this video prepared by DV2JHA. 2. Easy to build. This antenna build is intended to be very easy to replicate. Very few tools and materials needed to build one. No special parts needed. Anyone can build it. 3. Elegant design. Because it only has one feed point, you only need one dual-band VHF-UHF radio to use this antenna (instead of using two different radios and feed points for each band, thereby eliminating the need for a duplexer). The coaxial cable from the radio connects directly to the antenna (no baluns). To maximize the full capability of this antenna, use it with a radio with full-duplex capability. 4. Easy to tune. You only need to adjust the gap between the Moxon (VHF) driven element, and the Yagi-Uda (UHF) driven element to achieve perfect SWR. If you wish to move the center frequency (the frequency with the lowest SWR), adjust the length of the driven elements. 5. Lightweight. You will begin to appreciate this once you compare it with other antenna designs. Heavy antennas are not particularly useful for hand-held satellite work. 6. Portable. With the split-boom feature, you can easily store and transport this antenna. If needed, you can always disassemble and collapse everything into a very small package. 7. Durable. This antenna design is built to last a lifetime of satellite work. 8. Low-cost. How much does a commercial satellite antenna cost? To build this antenna, I spent an equivalent of 5 USD.
This antenna has been fully tested to work with satellites such as AO-91, AO-92, SO-50, IO-86, and PO-101 (Diwata 2). To build your own satellite antenna, kindly refer to the antenna plans below.
To view at full resolution, click here. Adapted from the original design by LY3LP. This particular version with a number of modifications is created by 4I1AWN. It uses 3 mm copper tubing elements.
To see this antenna in action (a recorded ‘live’ satellite demo), head directly to Satellite Communications. To view the portable radio setup I use with this antenna, head directly to Portable Radio Setup.
My portable satellite radio setup.
Portable radio setup in an easy-carry camera bag.
The DIY antenna described on this page was used during the live contact via Diwata 2 satellite’, reported on CNN Philippines
A go-box is essentially a bunch of radio equipment placed in a box for easy transport and storage. Go-boxes may vary on its size and contents depending on the intended application. To take a look at the go box I use for satellite work, click here.
On this page you will find information on how to access amateur radio satellites such as Diwata 2 (PO-101), AO-91, AO-92, IO-86, and SO-50. By using amateur radio satellites as voice repeater, it is possible to contact fellow satellite operators in nearby countries (such as Japan, Malaysia, Singapore, China, and anywhere in the Philippines) using only a 5W handheld transceiver.
We’ve observed last night’s super moon using a 4-inch f/9 telescope. While it is true that the moon will be closer to Earth during a super moon, the difference in size and brightness compared to a non-super moon is so small and so subtle that it will be very difficult to detect such an almost negligible difference, even for amateur astronomers who regularly observe the moon, and use astronomical equipment such as a telescope.
For featured photos, click here.
For tutorials on how to get started with astrophotography, click here.
For DIY astronomy projects useful for astrophotography, click here.
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We’ve visited the Philippine Air Force Aerospace Museum at the Villamor Air Base in Pasay City. The museum features a comprehensive history of the various aircraft and aircraft-related artifacts of the Philippine Air Force, as well as an outdoor exhibit of actual decommissioned aircraft. We were surprised to see a full-size model of the Apollo 11 Command Module in the museum.
A scale model of the Apollo 11 Command Module (CM)
To view more photos of this visit, head directly to my other blog.
