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PRODUCT SHOWCASE WeatherVox – an automatic weather station with telephone access Sphere Communications has launched an innovative weather station system called WeatherVox. It has all the main features of a normal weather station except that you can phone it from any­where and get a voice report of the weather over the last 24 hours. Most of us rely on the Australian Bureau of Meteorology for the nightly weather report but more individuals and organisa­ tions, the Bureau’s re­ ports are insufficient or not localised enough. For example, a rural fire brigade may be responsible for a large region of rugged mountainous country which is heavily forested. Access may be vary difficult and the weather may easily vary between extremes on the one day and from one small area to another. The only way to know the weather in each location is to have a weather 82  Silicon Chip station in each area. That may be well and good but how do you access the weather information which is being recorded? This was the question that exercised the minds of the people at Sphere Communications. They could see many applications for this device, among rural fire brigades, boating organisa­tions, golf clubs, life savers, fishermen, farmers, foresters or anyone with a need for specialised weather information. Even people with holiday homes or boats on remote moorings could have an application for this device. What Sphere Communications did was to design a computer to interface to an Ultimeter 2000 commercial weather station made by Peet Bros Company, Inc, a company based in New Jersey, USA. The computer interface reads all the weather data from the weather station and stores it in RAM. Then, when ac­ cessed by phone, it will give a voice report on all the weather information that it has been programmed to give. The voice used to deliver the weather information is that of wellknown Sydney radio & TV announcer Grant Goldman. His voice, or rather, many words and phrases, are stored in two ISD 2590P 90-second voice recorder ICs (this device was featured in the February 1994 issue of SILICON CHIP). The WeatherVox is a actually a sin­ gle board computer with an RS-232 input for the weather station connec­ tion and a tele­phone interface, using American RJ-11 and RJ-12 telephone sock­ ets, respectively. A number of functions within the WeatherVox can be addressed or changed by pushing buttons of a standard DTMF tone phone. Three levels of voice report are available on the Weather­Vox: Brief, Intermediate and Detailed. The Brief report includes time of day, current outdoor temperature, overnight low tempera­ ture and time at which it occurred, wind speed and direction, peak gust today and time of occur­ rence, average wind speed over the last ten minutes, average wind speed over the last minute, barometric pres­ sure, relative humidity and this week’s rainfall. The Intermediate report includes all of the Brief report’s details and adds this week’s rainfall, this month’s rainfall, this year year’s rainfall, wind chill and dew point. The detailed report includes all of the Brief and Interme­diate reports and adds highest and lowest temperature today and times of occurrence, highest and lowest temperature this month and times of occurrence plus the high­ est and lowest temperature this year and the times of occurrence. The parameters can be measured in a choice of unit: Temper­ atures can be recorded in Fahrenheit or Celsius; Wind speed can be metres/ second, knots, km/h or mph; Rainfall can be in centime­ tres, millimetres or inches; Barometric pressure can be millime­tres or inches of mercury, hectopascals or millibars and finally, wind direction can be in degrees or Cardinal points. All of this information is obtained in raw data form from the Ultimeter 2000. It is a compact self-contained unit with a large LCD screen and 16 pushbuttons to display the various read­ings on the screen. It has inbuilt sensors for tem­ perature and barometric pressure and has external sensors for wind speed and direction, rain gauge, temperature and humidity. The WeatherVox unit itself is a grey plastic box about the size of a VCR tape housing. It measures 110 x 200 x 30mm. It contains a multi-layer PC board that accommodates all the circui­try. It has been wholly designed and manufactured in Australia. It car­ ries an Austel permit: A95/12/0464. For more information, contact Sphere Communications, 161 Bunner­ ong Road, Kingsford, NSW 2032. Phone (02) 9344 9111; fax (02) 9349 5774. New loudspeakers from Jamo Jamo has just released a new range of loudspeakers called the “8-Series”. This consists of three bookshelf and two freestanding models plus matching centre and surround sound speakers. All have similar styling with a moulded front baffle and they are available in black or mahogany finish. All have a nominal im­pedance of 6#. The details of Jamo 8-Series are as follows. The Jamo 28 is a compact bookshelf with a 130mm woofer and a dome tweeter. Its power rating is 55 watts and it is priced at $399 a pair. The Jamo 38 is a slightly larger bookshelf, again with a 130mm woofer and a dome tweeter. It is rated at 60 watts and retails for $499 a pair. The model 68 is the largest bookshelf with a 165mm woofer and a dome tweeter. Its rating is 80 watts and retails for $699 a pair. The model 98 is a 2-way floor-stand­ ing speaker with two 165mm woofers and a dome tweeter. Its rating is 90 watts and it retails for $999 a pair. AUDIO MODULES broadcast quality Manufactured in Australia Harbuch Electronics Pty Ltd 9/40 Leighton Pl. HORNSBY 2077 Ph (02) 9476-5854 Fx (02) 9476-3231 BassBox® Design low frequency loudspeaker enclos­ures fast and accurately with BassBox® software. Uses both Thiele-Small and Electro-Mechanical parameters with equal ease. Includes X. Over 2.03 passive cross­over design program. $299.00 Plus $6.00 postage. Pay by cheque, Bankcard, Mastercard Visacard. EARTHQUAKE AUDIO PH: (02) 9948 3771 FAX: (02) 9948 8040 PO BOX 226 BALGOWLAH NSW 2093 THE “HIGH” THAT LASTS IS MADE IN THE U.S.A. Model KSN 1141 The new Powerline series of Motorola’s 2kHz Horn speakers incorporate protection circuitry which allows them to be used safely with amplifiers rated as high as 400 watts. This results in a product that is practically blowout proof. Based upon extensive testing, Motorola is offering a 36 month money back guarantee on this product should it burn out. Frequency Response: 1.8kHz - 30kHz Av. Sens: 92dB <at> 1m/2.83v (1 watt <at> 8Ω) Max. Power Handling Capacity: 400W Max. Temperature: 80°C Typ. Imp: appears as a 0.3µF capacitor Typical Frequency Response MOTOROLA PIEZO TWEETERS AVAILABLE FROM: DICK SMITH, JAYCAR, ALTRONICS AND OTHER GOOD AUDIO OUTLETS. IMPORTING DISTRIBUTOR: Freedman Electronics Pty Ltd, PO Box 3, Rydalmere NSW 2116. Phone: (02) 9638 6666. February 1997  83 Finally, the 128 is a large 3-way tower design with two 200mm woofers. It is rated at 140 watts and retails for $1499 a pair. Both floor-standing models have magnet­ic shielding of the drivers. All Jamo loudspeakers come with a 5-year warranty and are available from selected hifi dealers around Australia. For more information contact Scan Audio Pty Ltd by phoning 1 800 700 708; fax 03 9429 9309. Monolithic wireless IC converts both ways a range of phase-shift (PSK) half-du­ plex wireless digital communications transceivers. These includes wireless local area networks, time-division duplex quadrature modulated commu­ nications systems and time-division multiplex access packet protocol radios. Due to its power management mode, the HFA3724 is suitable for use on PCMIA cards and other portable ap­ plications such as wireless handsets. It comes in an 80-lead TQFP package. For further information, contact the Australian distributor for Harris Sem­ iconductor, BBS Electronics Australia Pty Ltd, Unit 24, 5-7 Anella Ave, Castle Hill, NSW 2154. Phone (02) 9894 5244; fax (02) 9894 5266. 1kV miniature ceramic capacitors The Harris HFA3724 is the world’s first monolithic IF/quad­rature mod­ ulator/demodulator which converts in both the receive and transmit di­ rections between baseband and inter­ mediate fre­quencies from 10-40MHz. The chip simplifies the design of KITS-R-US RF Products FMTX1 Kit $49 Single transistor 2.5 Watt Tx free running 12v-24V DC. FM band 88-108MHz. 500mV RMS audio sensitivity. FMTX2A Kit $49 A digital stereo coder using discrete components. XTAL locked subcarrier. Compatible with all our transmitters. FMTX2B Kit $49 3 stage XTAL locked 100MHz FM band 30mW output. Aust pre-emphasis. Quality specs. Optional 50mW upgrade $5. FMTX5 Kit $98 Both a FMTX2A & FMTX2B on 1 PCB. Pwt & audio routed. FME500 Kit $499 Broadcast specs. PLL 0.5 to 1 watt output narrowcast TX kit. Frequency set with Dip Switch. 220 Linear Amp Kit $499 2-15 watt output linear amp for FM band 50mW input. Simple design uses hybrid. SG1 Kit $399 Broadcast quality FM stereo coder. Uses op amps with selectable pre-emphasis. Other linear amps and kits available for broadcasters. 84  Silicon Chip Philips has recently extended its range of miniature ceram­ic capacitors with the release of a 1kV DC series. These are available in values from 0.47pF to 3300pF with tolerances of ±0.25pF or ±5% for SL types and ±10% or ±20% for class II types. The operating temperature range is PO Box 314 Blackwood SA 5051 Ph 0414 323099 Fax 088 270 3175 AWA FM721 FM-Tx board $19 Modify them as a 1 watt op Narrowcast Tx. Lots of good RF bits on PCB. AWA FM721 FM-Rx board $10 The complementary receiver for the above Tx. Full circuits provided for Rx or Tx. Xtals have been disabled. MAX Kit for PCs $169 Talk to the real world from a PC. 7 relays, ADC, DAC 8 TTL inputs & stepper driver with sample basic programs. ETI 1623 kit for PCs $69 24 lines as inputs or outputs DS-PTH-PCB and all parts. Easy to build, low cost. ETI DIGI-200 Watt Amp Kit $39 200W/2 125W/4 70W/8 from ±33 volt supply. 27,000 built since 1987. Easy to build. ROLA Digital Audio Software Call for full information about our range of digital cart players & multitrack recorders. ALL POSTAGE $6.80 Per Order FREE Steam Boat For every order over $100 re­ceive FREE a PUTT-PUTT steam boat kit. Available separately for $19.95, this is one of the greatest educational toys ever sold. -55°C to +85°C but types an extended operating temperature of +125 degrees C are also available. These latter types could be used in power sup­ plies, electronic ballasts and automotive applications. For further information, contact Philips Components, 34 Waterloo Rd, North Ryde, NSW 2213. Phone (02) 9805 4479. New colour printer from H-P has photo quality Hewlett Packard has released the HP DeskJet 690C colour inkjet print­ er for home and office use. The new printer in­ corp­o­rates HP’s Photo REt (Resolution Enhancement technology) for photo quality images and uses a new ink cartridge which quickly snaps into place along­ side the standard colour cartridge, when printing high resolution images. Naturally, for such images, the computer will need to be equipped with a colour scanner or CD-ROM drive to read photo-CDs. The HP Deskjet 690C will print at five pages a minute (PPM) for black and 1.7PPM for colour images. It has a recom­mended retail price of $654 including sales tax. The HP Photo Colour kit sells for $102 while HP photo paper is priced at $25 for 20 sheets of A4. Further information on HP products can be ob­ tained by phon­ing 131 147 (toll free).