Archive for category Radio Komunikasi

Frekwensi Bantuan Komunikasi Lebaran 2010

Sep 3

Posted by Mbah Paijo in Radio Komunikasi | 2 Comments

Buat Rekan-rekan yang mau mudik, hati-hati dijalan.
Arus kendaraan padat, utamakan keselamatan.

Bagi yang membawa radio, silahkan tune di frekwensi berikut ini untuk bantuan komunikasi.
Nanti akan di pandu tentang situasi jalan, jalur alernatif, kemacetan dan tentu sebagai teman dalam perjalanan.

Area Banyumas / Purwokerto:                                                  Baturaden (d/h. Rescue)
RX: 143.710                                                                         RX: 143.630
TX: 142.160                                                                               TX: 142.080

Purbalingga:                                                                               Wonosobo
RX: 142.650                                                                               RX: 143.150
TX: 141.100                                                                               TX: 142.030

Gombong: Kebumen
Direct: 142.470 Direct: 142.900
HF : 11.410 MHz Mode USB.

Purworejo:    RAPI Jateng
RX: 142.750                                                                              RX: 143.600
TX: 140.750                                                                            TX: 142.050
..                                                                                                 Coverage area: jabar, jateng, jatim

YANMAS:                                                                                    Triple One
RX: 148.130                                                                                RX: 141.110
TX: 149.130                                                                                TX: 149.130
Coverage area Jawa tengah, Jabar, jatim                                      Coverage: Jakarta – cirebon

RAPI Brebes
RX: 143.120 –> Inputnya kok sama dengan RAPI Jateng ya
TX: 142.050

RPU Jateng                                                                              RPU Jatim
RX: 146.780                                                                              RX: 141.680
TX: 146.72o                                                                              TX: 142.680

Bankom Nasional 1                                                                     Bankom Nasinal 2 / RAPI-DA JATIM
RX: 143.575                                                                              RX: 143.550
TX: 142.025                                                                              TX: 142.000

ORARI JAbar                                                                            ORARI Kebumen
VHF: 146.720                                                                            RX: 146.660
UHF: 434.580                                                                            TX: 145.660

Mohon rekan-rekan bisa melengkapi daftar frekwensi bantuan komunikasi baik RAPI / ORARI / Kesehatan ? dll.

Silahkan infokan ke kami di info@telomoyo.com

Semoga bermanfaat, hati-hati dijalan…..

Kegiatan Bankom RAPI Wilayah 26 Gombong – Jateng. Dalam Foto: Supriyanto, Mbah Paijo, Mas gembel, Pak Edi, dll

Review Icom IC-T7H

Aug 3

Posted by Mbah Paijo in Radio Komunikasi | 4 Comments

Pada tanggal 30 Juni 2010, ada seseorang dari seberang pulau Jawa.
Beliau tanya2 masalah radio.
Singkat kata singkat cerita, di belilah salah satu radio saya. Deal dengan harga yg disepakati.
Beliau cerita ada HT IC-7H. Saya tertarik sempat nyeletuk dihibahkan saja. Tapi tentu saja itu hanya bercanda… Masak ada yg mau menghibahkan radio hehehe.
Setelah tawar-tawar, maka saya beli radio itu. Dengan pembayaran dipotong dari radio yg saya jual.

Betapa kagetnya saya ketika lihat nilai transfer, jauh diatas harga radio yg saya jual. Wah apa tdk salah ini tranfer.
Saya kontak beliau, katanya tdk salah, utk uang capek…. wewwww…????
Dan kaget juga ketika T7H dikirim dan beliau tdk mau dibayar utk HT nya. Waduh… antara gak enak, serba salah dan macem-macem.

Semoga beliau diberi kemurahan rezqi, dilipat gandakan rezqinya oleh Yang Maha Kuasa. Sukses karir, sehat selalu beserta keluarga. Hanya ini yg bisa saya berikan.

RADIO….
Secara umumkondisinya oke. Fisik lumayan.
Saya ukur power dengan antena pada 13V keluar 5,5W. Kalau dengan dumyload mungkin bisa 6-7 watt. Ini adalah normal, power blm short.
Fungsi-fungsi masih normal semua.
Radio ini adalah kembaran dari IC-T7A. Tapi pada IC-T7A power yang keluar hanya 3 watt standar pabriknya.
Untuk T7H jika menggunakan batre AA maka akan keluar 2-3 watt saja. Karena batre AA voltase hanya 5,5V jika menggunakan rechargerable (@ 1,2V).
Saya pribadi lebih suka HT yang menggunakan batre AA. Kenapa? Karena mudah cari batrenya. Bisa diisi AA Recahargeable yang bisa diisi ulang.
Jika habis atau drop batrenya mudah dan murah untuk cari penggantinya. Jika pakai batre pack, jika batre drop cari gantinya mahal.
Antena bawaan kurang sensitif. Sama seperti radio lain. Maka untuk antena solusinya adalah diganti dengan yang after market. Pasti untuk TX/RX akan semakin bagus.

Rentang frekwensi RX Icom IC-T7H adalah 40 Mhz – 999 Mhz. Dengan mode AM dan FM saja.
Jadi meski mencakup frek radio broadcast (88-108 Mhz) dan TV (575-700 Mhz) radio ini tdk akan bisa menangkap siaran radio broadcast dan TV. Karena TV dan radio broadcast menggunakan mode WFM.
Frekwensi TX radio ini 40 – 500 Mhz. Cukup lebar, tapi harus hati2 TX di luar band amatir, karena antena yang ada didesain untuk TX di dual band saja (VHF/UHF).
Radio ini bisa menangkap airband (pesawat terbang).

Radio di hidupkan… calling-calling roger… bisa diterima lawan dengan jelas walau menggunakan antena bawaanya.Dengan bentuk yang sedang, tidak terlalu besar dan terlalu kecil, radio cocok buat dibawa kemana-mana. Apalagi dipadukan dengan acoustic tube mic/earpiece.

Kesimpulan saya, radio IC-T7H radio yang bagus. Cocok buat yang mau cari radio. Dengan power 6-7 watt pada 13,5V (menggunakan PS atau batre pack) maka ini sdh powerfull. Jika menggunakan batre AA power akan berkurang, tp radio akan awet.
Untuk yang hobi monitor, radio ini cocok dibuat koleksi juga. rentang frekwensi yang lebar (40-999 Mhz) bisa menangkap banyak frekwensi.
Kelemahanya adalah tdk ada mode WFM. Jadi tdk bisa menerima broadcast radio dan TV.
Silahkan buat yang mau berburu HT. Dipasaran masih ada yang jual baru. Tp maaf untuk radio ini TIDAK DIJUAL. Untuk koleksi pribadi.

Berikut Foto Icom IC-T7H, klik utk perbesar.

Icom IC-2GAT

Jul 22

Posted by Mbah Paijo in Radio Komunikasi | 7 Comments

Barusan dapat kiriman dari teman yang di Malang.
ICOM IC-2GAT. Spec bisa dilihat di http://www.universal-radio.com/catalog/ht/2gat.html
Lumayan buat ngebrik lokalan. Dengan DC-1 power keluar 5,5 watt. Soalnya DC-1 output cuma 11V.
Kalau pakai 13,8V bisa keluar 7 watt, asli dari icom. Frekwensi TX/RX 138.000 – 173.900.

Saya lebih suka ngebrik dengan HT, krn paling hanya lokal saja. Bahkan lebih sering pakai low power untuk 2GAT yang keluar 0,5 watt.
Dengan Low Power saja bisa sampai 20 KM (Gombong – Aliyan kebumen) walau agak noise krn ad nabrak bukit. Kalau pakai Hi Power clear sampai sana. Dipadukan dengan antena tuner dan G7 yang lokalan murmer dengan ketinggian antena hanya 5 meter dari tanah. Lumayanlah bisa sejauh 20KM dengan 0,5 watt ada bukit2nya lagi.

Klik gambar untuk perbesar.

Review Icom IC-R5

May 24

Posted by Mbah Paijo in Radio Komunikasi | No Comments

Klik Untuk perbesar

Spec:
- Frekwensi 100 Khz – 1300 Mhz
- Mode AM/FM/WFM
- 3,5mm jack mono
- 2x AA batre

IC-R5 adalah sebuah receiver. Seri R menunjukan bahwa itu singkatan dari receiver.
IC-R5 bentuknya sangat mungil. Menggunakan 2 buah batre AA dua biji. Radio ini cocok buat yang hobi nguping, enak buat diajak jalan-jalan.

Sebenarnya begitu mendengar kata recever dalam bayangan saya ini pasti canggih buat receive. Tentu lebih unggul jika dibanding dengan tranceiver soal receivenye.
Tapi kenyataanya saya kecewa begitu menerima pesawatnya.
Kecepan scan biasa saja, sama dengan transceiver lain spt yaesu VX3R. Kalah jauh dengan IC-R3 yang mampu scan 30 frek/detik.
Menu yang ada juga sangat sedikit.
Kepekaan juga biasa. Sama dengan radio lain.
Keluaran suara audio pakai jack 3,5mm mengecewakan. Hanya bunyi satu earphone saja. Suara tdk jernih, cenderung mendesis. Tapi jk earphoone dilepas suara lumayan jernih.
Batre bawaanya boros banget, setengah hari habis. Harus diganti dengan batre lain.

Keunggulan dari radio ini adalah bentuknya yang sangat kecil. Bisa memakai batre AA yang banyak beredar. Jadi kalau batre drop gampang carinya.

Dengan harga saat ini 1,750,000, saya akan lebih memilih Yaesu VX3R dg harga saat ini 1,8 juta.
IC-R5 Dibandingkan dengan VX3R.
- VX3R bisa transmit — R5 hanya RX
- VX3 pakai batre litium — R5 pakai batre AA mudah diganti
- VX3 ada frekwensi counter — R5 tdk ada
- VX3 ada smart search — R5 tdk ada
- Antena lebih peka punya R5
- Kecepatan scan sama
- VX3 frekwensi 1-999 mhz — R5 frekwensi 1-1300 Mhz
- VX3 mode stereo — R5 keluaran mono
- Menu lebih komplit VX3R

Spec IC-R5 sangat mirip dengan IC-Q7A. Bedanya IC-Q7A bisa transmit walau power kecil. Rentang frekwensi sama.

Review Yaesu FT-3000M

May 24

Posted by Mbah Paijo in Radio Komunikasi | 4 Comments

Klik untuk perbesar

Spec:
- RX: 110.000 – 999.000 / TX: 140.000 – 174.000
- Power 10 / 25 / 50 / 70 watt. 15A max.
- Dual frekwensi. Dual Watch, band scope.
- Half duplex, FULL Duplex
- Tone / TSQ / DCS

Saya dapet radio ini kondisi second. Alasan beli karena frekwensi radio ini lebar. Karena saya juga sering monitor frekwensi yang aneh-aneh.
Pertama pakai radio ini sangat bingung. Hand Mic hanya bisa untuk PTT saja. Angka2 dan tombol fuction gak fungsi. Katanya yang jual seh emang dari sananya gak bisa.
Semua menu harus diakses dari tombol-tombol yang ada di RIG. Kalau yang pernah pegang yaesu VX1 / VX2 / VX3 / IC-Q7A / dan sejenisnya pasti sdh terbiasa dengan menu spt ini.
Tombol rotary dial ada 2. Yang satu untuk step MHz yang satunya untuk Hz. Cukup memudahkan untuk penggesaran frekwensi.
Menu-menu sangat banyak, ciri khas yaesu untuk frekwensi lebar. Pengaturan duplex repeter juga sangat mudah. Hanya dengan 3 kali langkah sdh bisa disetting untuk repeter bebasnya.

Terdapat dua kipas di belakang bodi radio. Yang satu untuk putaran udara masuk, satunya keluar. Kipas akan berputar jika pesawat sdh mulai panas dan bekerja otomatis. Ini sangat membantu, tdk perlu kasih kipas tambahan.
Untuk dipasang di mobil sangat cocok. Krn sdh ada kipas otomatisnya. Untuk RIG jika tdk ada kipasnya running di hi-power akan sangat panas.
Modulasi mic yang diterima lawan bagus. Dominan tanpa ketinggalan.
Audio speker standar. Untuk penggunaan sehari0hari saya pakai speker external Kenwood. Suara sangat mantappp…

Kelemahanya jk tdk terbiasa dengan menunya akan terkesan sulit. Tapi jika sdh terbiasa akan mudah.
MIC hanya untuk PTT saja. Angka2 tdk berfungsi, jika ditekan malah merubah tingat power dan mode momory/vfo.
Radio ini memakan power yang besar, 15 Va. Jika power kurang maka akan “nggereng” radionya. Krn power besar, jika running di hi-power kadang konektor sekering di dc cord sangat panas. Jika sangat panas arus kadang putus sementara (buka sekering putus). Mungkin konektor sekeringnya kendor memuai jk panas. Padahal sdh pakai sekering 15A. Rencana mau saya by pass saja tdk pakai sekering. Krn Power Supply sdh ada protector jk short akan mati sendiri, relatif aman.

Secara umum saya sangat menyukai radio ini. Walau awalnya sangat bingung soal menunya.
Semoga radio ini awet di tempat saya….

Icom IC-R3 Unblock

May 17

Posted by Mbah Paijo in Radio Komunikasi | 2 Comments

Kali ini saya dapat Icom IC-R3 NOS alias New Old Stok. Dapat dari salah satu instansi.
Kondisinya kayaknya lama tersimpan. Dus nya sdh tdk keliatan spt baru. Maklum mungkin di taruh saja di instansi tsb. Tp kalau Radionya dijamin masih mak nyuss krn emang baru.
Kotak / kardus wall charger yang satu unit ada kehitaman dikit krn lama disimpan. Tp bukan jamuran loh. Hanya sedikit saja.. Mungkin krn kertas dismpan lama jd spt itu.

Yang disayangkan adalah wall chargernya 120V. Yach sama sekali tdk bisa digunakan disini (Indonesia).
Satu unit langsung saya potong kabelnya, disambungkan dengan charger lain. Toh wall charger 120V bawaanya ini benar2 gak bisa dipakai.

Kelengkapan Radio ini: Unit + Belt Clip + Wall charger 120V + Batre lithium + Spare batre untuk isi batre AA + Manual.
Semua blm pernah dipakai… tepatnya hanya dipakai untuk test saja.

Receiver ini adalah UNBLOCK version. Spt kita tahu, untuk versi USA sono yang beredar adalah yang selular block. Jadi frekwensi 815 – 870 MHz tdk bisa diakses. Padahal di frewkensi itu ada banyak yang mengudara spt polisi, instansi, dll. Juga 900 – 1300 Mhz versi USA tdk bisa diakses.
Yang saya miliki 2 unit ini adalah UNBLOCK, jadi semua frekwensi bisa diakses, No GAP. Frekwensi 100 Khz – 2450 Mhz.

Untul LCD saya blm tahu ini versi NTSC atau PAL. Krn saya test untuk TV blm bisa. Lokasi saya sangat jauh dari relay TV. Untuk nonton TV saja saya hrs pakai parabola. Jadi blm bisa test untuk jenis LCD nya.

Test secara umum bagus. Fungsi normal semua. Penerimaan amatir, Radio bradcast, airband semua oke. Sayang tempat saya jauh dari kota besar. Frekwensi UHF, 800 Mhz, 2400 Mhz (camera) tdk bisa ditangkap walau dengan antena tinggi. Jika nanti di kota besar akan saya coba kemampuanya.
Yang saya suka dari receiver ini VERY FAST SCANNING. Dari sekian banyak pesawat yang saya coba, blm ada yang mampu scaning secepat IC-R3.

Kalau menggunakan main LCD akan boros batre. Maka bisa digunakan sub LCD, yang LCD kecil dibawah itu. Jika hanya untuk monitor saja sebaiknya gunakan sub LCD dengan mode save power. Batre akan hemat sekali. Jika pakai external power suply bisa diguankan main LCD. Kecuali lagi jalan2 dekat hotel kalau mau scaning HIDDEN CAMERA di hotel biar keliatan videonya, sebaiknya bawa batre tambahan yang awet. Spt batre eneelop yang bisa di cas ulang.

Rencana satu unit saya pakai sendiri, satu unit saya lepas. Gak mungkin saya pakai semua heheheheheh

Berikut beberapa penampakan dari IC-R3. KLIK untuk perbesar………

Military Radio Communications Testing

Apr 8

Posted by Mbah Paijo in Radio Komunikasi | 2 Comments

The technology is used to test military voice over IP systems against a range of environmental conditions, whilst reducing the need for field trials.

Simulating Adverse Weather & Terrain Condition to Test Radio Over IP (ROIP) EquipmentArmed Forces around the world have, for many years, relied on analogue based radio systems to communicate between infantry, vehicles, aircraft etc and great strides have been made to make these more reliable and efficient. However, analogue based systems are increasingly being replaced with IP communications over radio networks as this allows not only voice to be sent but also data, including commands, positions etc.

The importance of Radio over IP (ROIP) to military operations was recently demonstrated by the announcement in January 2008 by US Central Command that it is now using its new RIPRNET (Radio-over-IP Router Network) for convoy operations in Iraq.

Unfortunately, all radio networks are subject to problems with terrain and adverse weather etc.. Troops, tanks etc, which are deployed in mountainous regions or built-in urban environments frequently suffer radio interference. This interference can be due to the local terrain or adverse weather conditions, and IP transmissions are particularly sensitive to this. And of course the interference could be deliberate as well.

Radio Over IP Network Environtment SimulationRecreating the Right Radio Networks in the Lab

Recognising these issues, the producers of Radio over IP [ROIP] equipment are looking for ways to ensure that any new products they are developing are capable of operating effectively in adverse conditions.

An approach to this has been to attempt to simulate field conditions by creating radio reflections and interference etc, in a laboratory whilst using radio reflectors and radio sources. Unfortunately, this approach is flawed. Using these methods to set-up a particular networked radio environment, never allows the re-creation of the same conditions, so you would never be able to repeat the test or make it just the way you want it – it would be difficult to get the reflector to get it right.

Itheon Networks, as a company that specializes in the testing and performance of IP based data applications is helping a leading defense sector contractor to develop simulated IP network environments that can be used to test the resilience of Radio over IP [ROIP] systems and equipment before they are actually deployed in the field. Itheon’s network emulation products enable the tester to program whatever conditions are desired, be it equivalent to mountains and rocky terrain, a violent thunderstorm or a battle environment.

Radio Network Emulation
Network Emulation Provides the Key

The defense contractor using Itheon’s technology researched the market place and found that the Itheon Network Emulator-Enterprise (INE-Enterprise) offered unique functionality to enable the reproduction of easily repeatable but very realistic test environments. Using wired connectors, INE is able to test devices and can emulate the behavior of radio networks, allowing for full and repeatable controls of issues such as data loss and interference.

Another unique feature is that it has built in to the system a concept of a shared radio net – including the ability to control the amount of time the radio net must have before another station begins transmitting. Additionally the ability to limit the maximum time a station can transmit before bring forced to cease transmission correctly mimics real world transmissions, as there can be only one transmitter operating at any given time on a given frequency.

Radio Thunderstorm TestingA Radio Thunderstorm in a Box!

Suppose for example, the testers know that the electrical conditions in a thunder storm are likely to adversely affect the Radio over IP communication devices being used out in the field – how do they test that? Do they sit with multiple devices in a field waiting for a thunder storm? No. By using INE – Enterprise they can create a virtual thunderstorm on an emulated radio net. So there is no need to wait for a thunderstorm to happen to test that condition – they can call the thunderstorm to order and further more can repeat the same conditions over and over again.

Repeatable, Consistent and Controlerable IP Network EmulatioThe big advantage is that all the variables that can happen out in the field conditions can be accurately created and controlled. One distinction that does need to be made, is that IP network emulation allows the data transmitted to have ‘real’ conditions such as packet drop / damage and reordering applied to it, as opposed to simulators that simply calculate the impact of the proposed changes.

Therefore, with emulation, it is a case of “what you see is genuinely what you get” and it allows testers of prototypes the ability to see exactly how radio communication devices are working in a ‘real’ networked scenario, and therefore fully comprehend how the ROIP will behave, in the field.

Reduce the Need for Field Trials

In addition to the ability to set up consistent and controllable ROIP test condition, using the Itheon Network Emulator also helps to reduce the need to conduct real field trials until much later to the product development lifecycle which can really help cut costs.

Itheon Network Emulators are also used to simulate satellite, ship to shore and land to air radio comms systems.

Radio Encryption for Military IP Networks: HF, VHF, UHF - HC-2650

The flexible and universal MultiCom Radio Encryption HC-2650 can be used for virtually all frequency ranges (HF, VHF, UHF, SatCom) and operating modes (narrowband/wideband digital voice encryption, data encryption, secure messaging, IP VPN). MultiCom Radio Encryption HC-2650 is suitable both for single channel applications (mobile, desktop) as well as for integration in multi-channel command and control systems. MultiCom Radio Encryption HC-2650 allows connection to all radio or military IP networks. The system is extremely robust and can be used it in vehicles, tanks, coastal and ocean-going ships, aircraft and helicopters.

TRC-20H Croatian made military radio based on PRC-515

Frequency range 2 to 30MHz with 1kHz step

PEP output power 20W or low 2W

TRC-20H with voice cripto and frequency hopping for secure comunications

Tags: Radio Militer

Military Long-Range 2-way Radios

Apr 8

Posted by Mbah Paijo in Radio Komunikasi | No Comments

The military have been using long-range two-way radios for nearly 100 years already, and naturally, the technologies used have changed a great deal in that time.

The first military radios were morse code transmitters and receivers, used in the trenches of the Great War in Europe, which nowadays is referred to as World War 1 (1914-1918).

Armies began to use 2-way radios to pass messages between the front lines and their battalion headquarters, because the army field telephones needed to have wires laid between both stations. And these telephone wires were easily damaged or cut by enemy action.

But wireless could still get a message through.

The early army radios were crude transmitters and receivers which only sent and received morse code signals. They needed large and heavy batteries to power them, their antennas made them prime targets for enemy snipers and artillery. What is more, the enemy would try to listen in to their radio signals and make sense of the information. So signals had to be coded or enciphered, which took time to put into code and more time at the other end to decode each message.

The world’s navies made good use of their long range two-way radios to send coded messages between ships, and to naval stations on shore who could relay those messages back to the home base.

And in both World War 1 and World War 2, Germany used its long-range radios to stay in touch with their U-Boats (submarines) which attacked convoys of supply ships and enemy vessels (usually British or US) that they hunted and destroyed very successfully.

And while military radio transmissions are always at the mercy of jamming attempts, the signallers found they could change frequencies without too much difficulty. (Modern military radios can do automatic frequency-hopping, controlled by an inbuilt computer chip, which allows the radio sets in a network to stay in touch but which makes it extremely difficult for an outsider to follow as they keep changing channels back and forth all over the place.)

By the time of the second world war (1939-1945) two-way radios were much more sophisticated. Most radio sets could use voice (amplitude modulation, or AM) as well as morse code (continuous wave, or CW).

Single Sideband (SSB) mode of transmission was not invented until the 1960s, I believe.

Unlike World War 1, where air force pilots had no radios (and no parachutes), military aircraft could stay in contact with their bases over distances of hundreds of miles – and the pilots could talk to other planes while they were in combat.

The military radios had been made smaller so they were more portable. Voice transmissions were used mostly for short range contacts, while CW or morse code was able to get through clearly over much longer distances.

Even spies could operate from enemy-occupied countries with small suitcase-sized radios and tap their secret messages back to their home base. They were at great risk from counter-intelligence forces who used radio detector vans to pinpoint where a transmission was coming from, and would rush to find and arrest the secret agent. And spies who were caught were usually tortured for information before being shot.

Modern military long-range 2-way radios include various army packsets which cover most of the HF (shortwave) bands. To stay small enough to be carried as a backpack, they usually have a maximum power of 20-25 Watts and cover around 200,000 possible channels between 2-30 MHz. Most can handle AM, SSB and CW signals and some have digital and encrypted modes, plus ALE (automatic link establishment) and frequency-hopping technologies.

Some licensed radio amateurs actually collect these military radios and use them, all perfectly legally. Secondhand military radios can be bought legally in the USA and in the UK. The problem is they will often need some repairs, and you probably have to make your own power supply or battery packs to suit. Also, even the newest ex-army radio sets are quite heavy so they will be very expensive to send through the post or by courier. You will occasionally see one on sale in eBay. But it is a case of Ceavat Emptor, which means buyer beware!

If you do a search for Green Radios or Military Radios, you will find more information. There are also very active groups to be found in Yahoo Groups.

I haven’t even mentioned Satellite Communications, which are very secure because they use satellites which are owned and controlled by the military themselves. However, the satellites are so expensive that only the biggest and richest of governments can afford their own satellites. So many armies, navies and air forces still use radio for their long range comms.

AN/PRC104 Photo

Tags: Militer

Alinco DR-620 Review

Mar 16

Posted by Mbah Paijo in Radio Komunikasi | 2 Comments

Ini adalah RIG dual band kedua saya setelah Yaesu FT-7800R.

Spec nya adalah:
- Frek TX: Dual Band
- Frek RX: 88-999 MHz.
- Dual Receive, Dual Volume, Dual Display
- Power VHF 50W, UHF 35W
- Internal Duplexter
- RX mode V+V / V+U / U+U
- Ada kipas otomatis di panel belakang
- LCD bisa dilepas dari bodi, ditaruh di dasboard atau meja
- Bisa cross band repeat dg sedikit pencet menu.

Pertama memakai radio ini saya agak bingung. menunya kurang praktis.
Memang radio ini bisa dual display. Tapi dia hanya bisa TX di bagian main display (A) saja. Di sub display (B) dia tdk bisa TX hanya monitor saja. Jadi kalau frekwensi di sub band mau dijadikan untuk TX, maka harus dipindah dulu ke main display (A).
Sub band hanya bisa menampilkan frekwensi 136-174, 420-470 dan 800-999 Mhz. Tdk bisa continue, sama persis dengan Yaesu VX7R. kalau main band bisa menampilkan 88-999 Mhz.

Oh ya, main Band dan Sub Band posisinya bisa dipindah2. Kadang Main di A (kiri), kadang bisa juga di B(Kanan). Kalau sub band mau untuk transmit, dia hrs dipindah ke A (main display), jadi main band pindah ke B (sub display).
Walau radio ini bisa terima U-U atau V-V tapi tdk bisa menampilkan 2 frekwensi yang sama bersamaan. Misal frekwensi amatir 136-174 bersama2 di A dan B. Atau 440 dan 450 di A dan B.
Dia hanya bisa menampilan yang beda area. Misal radio FM dan amatir, atau air band dan amatir. Kan sama-sama VHF. Kalau UHF nya 400 Mhz dan 800 Mhz.
Kalau A dan B sama2 radio atau air band atau sama2 amatir tdk bisa.

Radio ini mempunya display yang bisa dilepas, sama persis dengan FT-7800R. Tp kabel bawaanya sangat pendek. Yang punya saya sdh ada kabel extender kira2 satu meter. JAdi display RIG bisa ditaruh di meja, bodi dibawah.

Mempunyai kipas pendingin attached. Lagi2 sama persis dengan FT-7800. Jika PTT ditekan kipas akan berputar selama kira2 1 menit setelah PTT dilepas baru berhenti. Kipas ini disatu sisi sangat mebantu. Tp disiisi lain kadang mengganggu. Misal di malam hari yang hening kipas kadang berisik. Padahal kita hanya pakai 5 watt yang nota bene pesawat tdk panas, tdk perlu kipas. Tp kipas tetap saja berputar.

MIC memakai konektor ulir. Ini saya suka. Dari pada pakai konektor RJ yang kayak kabel LAN / tlp. Kalau konektor RJ lebih cepat rusak, apalagi jika tertarik-tarik.
Ada internal duplexter. TApi fungsi ini saya gak bisa begitu mengerti.

Ini adalah radio RIG pertama saya yang ada mode WFM. Jadi bisa denger suara radio. Sayang tdk bisa untuk TV. Walau sebenarnya bisa juga krn mode WFM. Tp frekwensinya gak tdk tercakup. TV frekwensinya 570-799 Mhz. Radio di DR620 lumayan peka. Beberapa radio dari malaysia dan singapore bisa saya tangkap dari kota bengkalis.

Dengan power 50 watt untuk VHF saya rasa sdh cukup jika hanya untuk cuap-cuap say hello. Toh saya perlunya radio juga untuk komunikasi, bukan untuk pentung-pentungan. Modal blm ada jk untuk mentung orang. Dengan 50 watt sdh bagus diterima lawan bicara dari jarak 150KM (laut view). Sayapun tdk kesulitan menerima lawan bicara dengan jarak yang lumayan jauh.

Kelebihan:
- Wide band RX, dual band TX
- Bisa radio FM
- LCD bisa dilepas
- Ada kipas walau kadang mengganggu
- Bisa cross band dengan sedikit modif (non standar spec)

Kekurangan:
- menu rumit menurut saya. Hrs pindah2 dari main ke sub jk mau tukar TX
- Tdk bisa TX V-V di band yang sama (misal 144 dan 143)
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Tags: ALINCO

Antena Discone

Jan 11

Posted by Mbah Paijo in Radio Komunikasi | 11 Comments

A discone antenna is a version of a biconical antenna in which one of the cones is replaced by a disc. It is usually mounted vertically, with the disc at the top and the cone beneath.

Omnidirectional, vertically polarized and exhibiting unity gain, it is exceptionally wideband, offering a frequency range ratio of up to ~10:1. The radiation pattern in the horizontal plane is quite narrow, making its sensitivity highest in the plane parallel to the Earth.

History

On February 6, 1945, Armig G. Kandoian of New York was awarded patent number 2,368,663 [1] (assignor to Federal Telephone and Radio Corporation (later merged with ITT Corporation) for a “broad band antenna”, from an application made on May 15, 1943.

Excerpt from the Kandoian patent:

In keeping with progress made during the last few years in the development of ultra-high frequency radio technique, and applications thereof to aircraft communication, direction finding, and so forth, it has become necessary to develop special antennas and antenna systems suitable for installation on such aircraft. Flying conditions are such that these antennas must necessarily be small and rigid in their construction and also offer a minimum of wind resistance, in order that the flying efficiency of the aircraft will be unimpaired. In accordance with my invention I have provided a small rigid antenna suitable for mounting on the surface of the fuselage or other component of the airplane structure and in certain embodiments I have also provided a streamlined protecting shield or housing covering or so cooperating with the construction of the antenna system as to greatly reduce wind resistance.

Aplications

The discone’s wideband coverage makes it attractive in commercial, military, amateur radio and radio scanner applications.

When employed as a transmitting antenna, it is often less efficient than an antenna designed for a more limited frequency range. SWR (standing wave ratio) is typically ~2:1 over the range of the design frequency to the second harmonic and ~3.1 thereafter.

The discone’s inherently wideband nature permits it to broadcast undesirable spurious emissions from faulty or improperly filtered transmitters.

Construction Materials

A discone may be made from solid metal sheet (often copper), which is practical for small indoor UHF antennas, such as for Wi-Fi.

At lower frequencies a sufficient number of metal wires or rods in a spoke configuration is often used to approximate a solid surface. This simplifies construction and reduces wind loading.

The spokes may be made of stiff wire, brazing rods or even coat hanger wire.

The optimal number of rods comprising the disc and cone is often quoted as being from 8 to 16.

Components

A discone antenna typically has at least three major components: the disc, the cone, and the insulator.

The Disc

The disc should have an overall diameter of 0.7 times a quarter wavelength of the antenna’s minimum frequency.

The antenna’s feed point is at the center of the disc. It is usually fed with 50-ohm coaxial cable, with the center conductor connected to the disc, and the outer conductor to the cone.

The Cone

The length of the cone should be a quarter wavelength of the antenna’s minimum operating frequency.

The cone angle is generally from 25 to 40 degrees.

The Insulator

The disc and cone must be separated by an insulator, the dimensions of which determine some of the antenna’s properties.

Extending Low-Frequency Response

A vertical whip may be placed affixed vertically to the disc in order to extend the low frequency response, but this may reduce efficiency at higher frequencies. In this configuration, at lower frequencies the discone may more closely resemble a ground plane antenna or a coaxial dipole.

Picture: