Pallets RF amplifier 144 MHz, coupled with Wilkinson coaxial cables by I0FTG

How to achieve Pallet RF high power devices for VHF, using the SD2942 MOSFET power devices, reliable and affordable for amateur radio operators who can then assemble one or more Pallets RF power, as well as describes in his interesting article of IØFTG, Pippo. – Thanks Joseph for this courtesy and for the excellent work.   – [IØFTG you can reach at > [email protected]]

“” Da qualche anno il mercato dello stato solido LD Mos si è “arricchito” con dispositivi da oltre 1kWatt CW. – Il rovescio della medaglia è l’alto costo del dispositivo e la conoscenza delle tecniche d’impiego che risultano poco note alla maggioranza degli improvvisati utilizzatori. – La mia esperienza professionale, maturata nei laboratori R&D delle aziende che progettano e costruiscono TX analogici e digitali per il broadcasting, mi suggerisce che un amplificatore con un solo dispositivo è a rischio durante il servizio, essendo senza ridondanza……..e quando si rompe, oltre al fermo dell’attività, per le tasche di un radioamatore sono dolori!
La mia proposta è quella di utilizzare un dispositivo, di potenza più bassa, immesso nel mercato da oltre cinque anni con buone doti, sia robustezza, sia di costo: il Mosfet di potenza SD2942 o SD2942 in versione custom. Il progetto è nato circa un anno addietro ed è stato eseguito per ottenere un amplificatore da circa 400 Watt, da un solo dispositivo, per la banda dei 6 metri.”"
(Please click the images below to enlarge !!)

Qui a fianco il progetto tramite CAD meccanico 3 D per la posizione ottimale dei componenti. – Il progetto prevede un filtro passo basso a bordo che elimina tutte le armoniche in uscita ad oltre -60dB rispetto il picco di potenza d’uscita. Il dispositivo è un “geminato” in altre parole all’interno del “case” sono contenuti due dispositivi con unico “source”.
Questo consente di ottenere un amplificatore push–pull che, se ben bilanciato, riduce drasticamente tutte le armoniche pari in uscita.

L’amplificatore di potenza è stato progettato come un “pallet RF” professionale, in altre parole si compone di tre elementi base; un supporto in alluminio fresato, un circuito stampato d’ingresso e un circuito stampato d’uscita (naturalmente i due stampati sono a doppia faccia). Si evidenzia, che il circuito stampato d’ingresso comprende anche il circuito di bias; il circuito stampato d’uscita comprende anche il filtro passo basso.

Due pallet RF accoppiati consentono di ottenere oltre 750 Watt con un semplice divisore e sommatore due vie (wilkinson); questo è realizzato con semplici cavi coassiali da 75 ohm e relativi resistori da 100 ohm, per lo sbilanciamento in caso di guasto di un pallet RF. Questa sistemistica consente di avere una ridondanza, in caso di guasto di un pallet RF si continua a trasmettere con una riduzione della potenza d’uscita (-6dB rispetto l’uscita totale). Quindi un amplificatore molto concorrenziale rispetto a quello ottenuto con un solo dispositivo di ultima generazione. Pochi giorni addietro ho progettato e realizzato la versione per i 2 metri, la potenza d’uscita risulta di circa 320 Watt all’uscita del filtro passo basso; sono stati utilizzati gli stessi elementi base del 6 metri con piccole modifiche ai due circuiti stampati.

Utilizzando la stessa tecnica del 6 metri, per accoppiare due pallet RF, si ottengono circa 600 Watt in uscita (ridondanti, in caso di guasto, durante un contest). L’immagine a lato indica il test di due pallet RF, per i 2 metri, accoppiati tramite Wilkinson in cavo coassiale: è visibile lo spettro in uscita con la sola fondamentale (la misura reale della potenza è effettuata tramite bolometro)

Un punto di “forza” dei due pallet RF (6 e 2 metri) è il basso prezzo del Mosfet in caso di sostituzione: ho una buona scorta di dispositivi, messi a disposizione di chi acquista il pallet RF, ad un prezzo molto basso ovvero alla portata delle “tasche” di un radioamatore medio.

Altro punto di “forza”: non bisogna equipaggiarsi di un filtro d’uscita, nei pallet RF “della concorrenza” non sono compresi, è considerato un complemento d’acquistare a parte.

L’ultima mia “fatica”, in ordine di tempo, è l’accoppiatore direzionale d’uscita da abbinare alla scheda servizi: in caso di antenna rotta…….. l’amplificatore si blocca! – Come anche indicato sulla foto qui a lato: sopra l’accoppiatore direzionale per un amplificatore da circa 500 Watt, sotto quello da 1kWatt già assemblato con l’uscita del sommatore di Wilkinson per due gruppi di due pallet (out da oltre 1.1 kWatt). – La direzzionalità ottenuta, per la misura della potenza riflessa, è di oltre 30dB: un risultato similare ad un complemento passivo professionale! – Nella foto, sono stati messi accanto agli accoppiatori due toroidi; questi costituiscono il “cuore” per il funzionamento dei due complementi. -

L’amplificatore si completa, sia per un uso in stazione, sia in portatile, tramite un buon alimentatore da tarare a 42 Volt massimi, con una capacità ad erogare 15 Ampere per ogni pallet RF; una coppia di relè coassiali con quello d’uscita dimensionato correttamente; un dissipatore ventilato; una scheda servizi per gestire ritardi e preamplificatore, infine un buon contenitore………
Buon lavoro a chi ama divertirsi anche con il saldatore oltre al microfono! 73, Pippo, IØFTG. [mail: [email protected]] – - Link to: Web-page > RF-DesCom

Baofeng UV-3R MkII Dual band HT and the VGC co. UV-X4 similar feature – FCC / CE ok!

The Baofeng UV-3R Mark II  Dual-Band HT VHF UHF Dual frequency on display, Dual Watch – They copied the VX-3R ?… very similar indeed – at least on the outside!! – US Market List Price $69.99 / Special save: $59.99 US  - (source: Fleetwood web,  powered by ©CafePress.com)

For European customers,1750Hz tone burst is standard. For North Americans, unlike other micro radios, we offer 5k frequency spacing. The dual-band DSP chip also allows you to work U/V -
The UV-3R Mk-II Transceiver has also passed CE, FCC and RoHS certification – !!…now, we buy regular equipment !!

Again the ©VGC Vero Global Communication Co.,LTD has announced another model similar to the UV-3R: the UV-X4 Dual Band Dual Watch Pocket Radio – Change the type of buttons on the front panel and Color body! –  See the ©VGC image (click to enlarge) –  Only the model name, trade name, and FCC ID are different. – The CE Code 0678 (!) is identical

[Note] Change the FCC ID of identification from the Baofeng Co., Ltd UV-3R Mk II (currently approved device) to the new VGC Co., Ltd  UV-4X (electrically identical). – This….  for purpose of marcheting.

Link to: Download the (first) UV-X4 brochure in PDF (from vgc hk)
Link to: The UV-3R Baofeng Yahoo Group support and discussion

[Note]: This Radio Requires a License – !! Use Responsibly:
It is the buyers responsibility to ensure that your Two Way Radio or Amateur Radio is operated under, and controlled, within the laws that govern your respected area – Please consult your local radio/spectrum/government agency prior to any and all use

TH-D72 V/U APRS Launch in December 2010. The News Release and Jp Brochure

TH-D72A and TH-D72E Data Communicator FM Dual Bander -(Click image to enlarge) See the Link below for Download the Brochure in Japanese lang. and the TH-D72 News Release in EN  and Prices Jp and US and more…

Kenwood has announced it is launching 2 new FM dual band transceivers in December 2010. Featuring a high-performance GPS receiver, the TH-D72A and TH-D72E support a easy APRS® operation without requiring a computer and wide range of APRS® (Automatic Packet Reporting System) functions can be used if the TH-D72A/E is connected to a PC with the  supplied USB cable to enable control of the TNC.

TH-D72 144/430MHz FMデュアルバンダー – 高性能GPSユニットを内蔵。 – データ通信システム「APRS®」を標準搭載。- 操作性、視認性を考慮したデザイン。
(Click image to enlarge) Display DF0TK  APRS® operation
TH-D72A/E 144/430-144/440 MHz FM Data Communicator FM

Japan Prices:  Kenwood Suggested retail price: 62,790 yen – (excl. tax: 59,800 yen)
US Prices:  List Price:   $512.00 – Your Price: $499.00 (by Universal Radio)

Main Features:

The EME Conference 2010 in Dallas US – KP4AO on the air for 432 MHz EME

International EME Conference, 2010 (August 12-14, 2010) takes place in Dallas, Texas – Noise Figure Workshop – EME Demonstration by WA5WCP – Dealer Room featuring a number of dealers, – Tours of historic sites and Ladies program. The EME conference will conclude with the traditional Saturday night banquet! — My friend I0NAA Mario (ARI Honor Rool) will be the EME Conference in Dallas!

Moon-bounce from Arecibo Observatory (KP4AO AOARC), last April 2010. (Source: QST August, 2010)

Joe Taylor, K1JT, and Jim Breakall, WA3FET (left), together with a team from KP4AO, the Arecibo Observatory Radio Club, completed almost 250 contacts via EME using the Arecibo Observatory at the National Astronomical and ionospheric Center in Puerto Rico. (Insert photo by QST August 2010 Cover). –  (Click the image for enlarge)
Equipment Setup for 432 MHz EME: For extra flexibility we used two TS-2000, one for trasmitting and one for receiver, included a GaAsFET pre-amp with noise figure 0.5 dB. We had two power amplifiers, one using a 3CX800 we started with 350 W. - [Note]: Read, please, the entire report on QST, Aug. 2010 written by Joe, K1JT, Angel,WP3R and Jim, WA3FET.

Link to:  The Page’s WSJT, MAP65, WSRP and WSJT8 available for testing (Many thanks Joe, K1JT)

International EME Conference, 2010 takes place in Dallas, Texas

[Nota]: EME Communications (Earth Moon Earth) also known as moon bounce, is a Hamateur 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!

W5LUA, VE4MA, WA8RJF and the North Texas Microwave Society officially announce the 14th International EME Conference in Dallas, Texas on the 12th,13th and 14th of August 2010. The conference Hotel is The Westin at the Dallas Fort Worth Airport which is just a short shuttle ride from DFW Airport. We have over 100 pre-registered for the conference. To see if you are fully registered, please go to http://www.ntms.org/eme/ and check the  “Registered Attendees.

E.M.E. Conference 2008, there were more than 168 EME Operators at the 13th International EME Conference 2008 in Florence, Italy (Click on the left to very impressive big image). Ricordo che a Firenza si è tenuta la 13° Conferenza Mondiale EME nel 2008 organizzata in Italia dal CRT Toscana, a cui parteciparono ben 168 Operatori dalle varie parti del mondo. (Cliccare la piccola immagine qui sopra per vedere la grande foto ricordo 2008!!)

Paul, WA5WCP, will be giving an EME demonstration on 1296 MHz out in the hotel parking lot. On Friday at 1800Z (1PM Local) the moon will be up at 22 degrees elevation. This is a low declination moon which won’t give us very much time towards Europe. System will be a 12 ft dish and several watts. Paul will also be on after about 1900Z on Saturday.

Link to: 2010, Intern Confer EME – General Conferenze schedule
Link to: 2008, Intern Confer EME in Firenze Italy – Report and photo

Leggi tutto l’articolo in italiano qui di seguito….. leggi tutto/full story

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IC-9100 at last Ham Radio, 2010….. The projected release is araund October

At Friedrichshafen, last Ham radio 28 June, 2010, Icom Europe said that the IC-9100 would be released around September / October — The projected release is around October 2010!
Watch the photo inside the IC-9100 (click below for larger images) !!→ Updating: Andrews Comm  Now it is * Due Sept/Oct? (see the link below)

The IC-9100 covers 100W on HF, 50MHz and 144MHz, 75W on 430/440MHz and 10W on 1200MHz (option). The radio simultaneously receives two different bands (1. HF/50MHz + VHF/UHF – 2. VHF + UHF – 3. 430/440MHz + 1200MHz) and works as if there are two independent receivers in one radio. (Source by © 2010 Icom Inc)

Two 32-bit DSP and double conversion superheterodyne → Each main and sub-receiver has a dedicated DSP unit → The D-STAR mode (option) is available in 28MHz and 50MHz  bands simplex mode as well as in VHF and UHF bands → USB connector for PC control → Modulator, received audio,  RTTY demodulator, DV mode data can also be transferred over the USB cable  → GPS position reporting functions → Satellite mode operation or even moonbounce → Optional CS-9100 programming Software → The built-in RTTY demodulator and decoder → Optional 1st IF filters for HF/50MHz bands → Optional D-STAR DV mode UT-121 Unit → And more Features: → Download the  new Brochure released from Icom Inc. (Link below)

Link to:  Icom America IC-9100 –  has updated their web page
Link to:  Download the new Pre-release Icom inc (14.05.2010) – 2.6MB .PDF
Link to: The IC-9100 web-page by Adam,VA7OJ/AB4OJ

TS-590S new HF/50MHz Transceiver. TH-D72 APRS® Dual Band HT – 1st Video at Dayton

TS-590S HF/50 MHz Transceiver and New TH-D72 APRS® Dual Band FM Portable with internal GPS and a mini-USB connector (See the photo below) – The TS-590 in the Kenwood booth at Dayton Hamvention 2010 – Photo: click for larger image - (by www.radiocronache.com®)

Press Releases, May 7, 2010:  Kenwood Corporation, an operating company of the JVC Kenwood Group, is proud to announce the autumn/winter launch of two new Amateur Radio transceivers: the TS-590S and TH-D72. – Watch the 1st video at the Dayton Ham below !!

[Kenwood announces]: Anyone interested in these two models will be able to view product samples at: Dayton Hamvention 2010 (Dayton, Ohio, USA, May 14-16), and HAM RADIO 2010 (Friedrichshafen, Germany,  June 25-27).
APRSハンディ「TH-D72」、HF～50固定機「TS-590」[アマチュア無線] – デイトンでお目見えするそうです

TH-D72 Video 15.05.2010: A quick look at the NEW Kenwood TH-D72 APRS HT. Shot this on location at the 2010 Dayton Hamvention by W6GPS,Donald H Arnold,Jr (very interesting, thanks)

Link to: Kenwood Corporation – EN Complete News Release

Kenwood Corporation, una società operativa del Gruppo JVC Kenwood, è orgogliosa di annunciare che in autunno/inverno prossimi lamcerà due nuovi transceiver per Radioamatori: il TS-590S HF/50 MHz All Mode, basato su 32-bit floating-point DSP  e il nuovo TH-D72 APRS® Dual Band FM portatile dotato anche di un connettore mini USB e GPS incorporato

Kenwood annuncia che i due prototipi vengono esposti sia alla  Dayton Hamvention 2010, che alla Ham Radio DE in June 2010 !! -

Yesu VX-8DR Tri-band and VX-8GR Dual Band GPS/APRS® enhanced. FTM-350R Bug Fixed

VX-8DR All-in-one Tri-band (50/144/430 MHz) Transceiver Bluetooth for hands-free Operation with optional accessories. Waterproof/Submersible IPX7 rated-3ft for 30 minutes (Optional FGP-2 GPS and antenna unit, CT-136 Adapter or MH-74a7a external mic. for GPS/APRS® operation) -

VX-8GR 144/430 Dual Band Transceover with GPS unit included Built-in GPS Antenna which is based on a 12-channel receiver for GPS/APRS® operation.  Wide Band Receiver for 108-999 MHz, IPX-5 Water jets. – A  lower cost V/U APRS® handheld.
Minus a few VX-8R/DR features you may not need: No 6m – TX/RX – No 220 TX/RX – No HF RX – No Bluetooth – No SU-1 Barometer sensor – No WFM RX – No water immersion.
!! See more info, Price, Link and FTM-350R Bug Fixed …..below
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IC-9100 HF/50MHz + V/UHF Satellite Base Station Shown at Tokyo 09. Update now

The all-round transceiver IC-9100: HF/50 MHz (100W) 144/430 MHz (50W) 1200 MHz (10W) with optional 1.2 GHz UX-9100 module. Optional D-STAR Unit, DV mode operation on the esport version.

* HF/50MHz, 144/430 (440)MHz  &1200MHz coverage (UX-9100 Optional)
* 100W     on HF/50/144MHz
* 75W     on 430 (440)MHz
* 10W     on 1200MHz >(UX-9100 Unit Optional)
* Roofing     15kHz (FL.431 3kHz/ FL-430 6kHz 1st IF Optional for HF/50MHz)
* D-STAR DV (D-STAR Unit optional in combination with operating bands and mode)
* Satellite mode operation
* SSB, CW, RTTY, AM, FM & DV (D-STAR optional)
* 32-bit floating point DSP & 24-bit AD/DA converter
* Double superheterodyne with 2nd IF image rejection mixer
* This device requires 13.8 VDC

Icom introduces a direct competitor to the Kenwood TS-2000 TS-2000x!…. The IC-9100 has only one main DSP unit. In the 9100′s price class, it would not be cost-effective to include a second DSP board (ADC, DSP, DAC, support IC’s) for dual receive. No VHF and UHF at the same time.

アイコムよりHF～1200MHz固定機が参考出品されるようです。

See the Link below for download the Pre-release product information .PDF 2.2MB

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FTM-350 new APRS capable Mobile Amateur VHF/UHF was on display at the Tokyo Ham Fair 2009

The Yaesu FTM-350 new APRS capable Mobile Amateur VHF/UHF was on display at the Tokyo Ham Fair 22 August, 2009.
The new FTM-350 GPS/APRS Yaesu’s answer to the Kenwood TM-D710. Standard FTM-350 upgrades the FTM-10 to add packet radio and GPS/APRS capabilities and very large LCD with a radical change of style! Recalls the style of competitors Kenwood TM-D710 and Icom IC-2820. Now the functions of the controls are on the edge of the LCD…….

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IC-E80D Vs IC-E91D Disply and Panel-Key. D-STAR Hot Spot V2.29 is available! Satoshi Node Adapter and..

IC-E80D Vs IC-E91D Disply and Panel-Key. D-STAR Hot Spot V2.29 is available with latest Node Adapter, PCBs and PICs are available from Satoshi Yasuda 7M3TJZ/AD6GZ . More news:  see the info and data with the link below

The IC-E91D and IC-E92D Using a large full dot-matrix LCD! VHF/UHF Dual Band. D-STAR DV mode and 950 bps data capability with the optional UT-121.

Wideband receiver* with V/V, U/U dualwatch capability (*1 Receiver range differs from depending on version)

The IC-E80D Using LCD and keypad backlighting! Switchable VHF/UHF dual bande. Can transmit and receive D-STAR format digital voice and 950 bps data communication, simultaneously….

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