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Radio and Electronics Association of Southern Tasmanian Inc.
2006 Events and Meetings

2006 Events/Meetings/Gatherings:

Date

Event

Wednesday 6 December 2006

End of Year BBQ

We had about 20 people enjoy the free BBQ last Wednesday night up on the Domain. It was a nice weather and a good social night was had by all with all our food being consumed along with some strange amber liquid HIHI.

We had a great brainstorming session on visits, talks and activities for 2007, so, watch this space, thanks guys.

2006 has been a very full year for REAST with many activities, things to see, do and be involved with, in the area of amateur radio and associated disciplines and 2007 is shaping up to be an even bigger year.

I’m not sure about you but I’m looking forward to a rest over the Christmas break and playing a little radio.Goto Top of Page

Seasons greetings from Justin, VK7TW

Saturday 2 
December 2006

VK7 HamFest - Miena, Central Highlands hosted by CHARCT.

The following wrap-up of the Hamfest comes courtesy of Dave, VK7KDO:

Well, in fine Tasmanian tradition the weather really turned it on for us with four seasons in one day including snow but for those that attended I did not hear one complaint about the facilities and certainly inside the hall was VERY comfortable.

VK7_Hamfest_2006.jpg (95347 bytes)

The sprint to the car park depending on what season you chose to do it in was a little bracing!

We certainly over-catered in the food department and the unused surplus food and other items were donated to the hall committee for the pending central highlands Christmas party. My thanks go to those who put in a considerable effort in the kitchen and in other areas on the day to make the event run smoothly. I do not intend to name them but they know who they are.

REAST_Stand_Hamfest_2006.jpg (95766 bytes)Goto Top of PageThe REAST Stand with that warm luxeon glow!!

From door takings we had numbers at 173 and it was good to see some of our older amateurs making the effort to attend, one of the major traders stated that it was a better turn up than the Shepperton ham fest.

The competitions held through the day especially the morse code contest added some humour to the event and those lucky enough to win walked away with a nice prize.

Mitchell_onkey_Hamfest_2006.jpg (109526 bytes)Mitchell on the foot operated key

VK7RO_Hamfest_2006.jpg (201087 bytes)Richard the Morse contest invigilator (with innovative pre-loved equip sandwich board!)

All traders were satisfied with their sales on the day and if you chose your mark you could certainly pick up a bargain with prices in some cases hundreds of dollars below that seen advertised in AR Magazine.

Given the difficulty in accessing much radio and associated equipment in Tasmania and having to purchase sight unseen and with considerable freight costs involved it was certainly an opportunity to view some of the latest in ham radio gear and purchase items for the shack.

Whilst on the subject of traders, some coming from as far a field as Western Australia and incurring considerable costs getting here, without their support there would be no ham fest. When next you are considering a purchase remember those people that supported our ham fest and give them a chance to meet your needs.Goto Top of Page

The day finished off with the committee of The Central Highlands Amateur Radio Club and our trader visitors returning to our holiday home and enjoying a well earned rest, steak dinner and glass of wine.

Once again thank you to those who supported us I hope you had a great day.

(Cheers from Dave VK7KDO, Convenor)

Sunday 5 November 2006

2006 Sewing Circle BBQ

Sunday the 5th November was the Sewing Circle BBQ and by all accounts it was a great success. According to the attendance record we had over 60 people come up to the Domain and enjoy the day.

SS_BBQ.jpg (116702 bytes)The BBQ area

The broadcast started proceedings with the WIA National broadcast then a special treat of the VK7 Regional News Broadcast coming from the ATV studios and originating both from Repeater 2 and ATV on 444.25MHz. The broadcast was read by both John VK7JK and Ian VK7IR who were both well dressed presenters HIHI.Goto Top of Page

ATV_VK7_News_Broadcast_A.jpg (53993 bytes)Ian, VK7IR & John VK7JK reading the VK7 Regional news on ATV (photo courtesy of Harvey VK7HLE)

ATV_VK7_News_Broadcast_B.jpg (54098 bytes)(photo courtesy of Harvey VK7HLE)

ATV_VK7_News_Broadcast_C.jpg (135682 bytes)ATV Floor Manager Ken, VK7DY and assistant Clayton, VK7ZCR (photo courtesy of Harvey VK7HLE)

From the broadcast we went into the BBQ lunch, pre-loved equipment sales and mingling around the displays that were running throughout the day. There was a display of APRS on the Macintosh, SSTV on 20m on the PC that was connected to the club station VK7OTC. There was a display of what amateur radio is all about at REAST. Even a display of one of Mike Groth VK7MJ's optical transceivers that used the night before to set the inaugural digital DX record on the optical band.

SS_BBQ_A.jpg (28889 bytes)Inside displays and shrouded honour roll!

The ATV studio was open for people to inspect and video broadcasts where run throughout the day. Dave VK7DM gave a talk on repeaters and explained the ins and outs of repeater operation with repeater two the willing candidate!

7DM_Repeater_Talk_SS_BBQ.jpg (19726 bytes)7DM explaining about repeaters

We started the official part of the day with Bill VK7AAW giving us a great outline of how the Sewing Circle BBQ started way back at Forcett and there were a number of people present who attended the original BBQ gatherings. Then Ken, VK7DY presented the Terry Wilson VK7HTW (silent key) memorial award for services to Amateur Radio for 2006 to Ben, VK7HAH.

7dy-7hah-terrywilsonaward_B.jpg (29527 bytes)7DY presenting 7HAH with VK7HTW (SK) award

Phil, VK7ZAX then unveiled the VK7 Divisional Honour Roll after a great speech which acknowledged the near-on 80 year heritage of amateur radio in VK7 and I include a small segment of the speech here:

“So many of those listed have passed on, but I will mention a few. Phil Fysh, VK7PF, whoGoto Top of Page attended the first National Convention in Perth WA in 1925, and on his return convinced  Tasmanian amateurs of the need for greater participation in Institute affairs, leading to incorporation of the Division in 1925. The first President, A. Harold Masters, architect, & lecturer in Electrical engineering at Launceston Tech. is credited with being the first person in Tasmania to demonstrate communication by Wireless Telegraphy. “Pop” Medhurst, VK7AH with Mr. Hallam successfully communicated with a visiting warship over distances of up to 60 miles in July 1901. Institute patrons have been “Pop” Medhurst and Len Crooks VK7BQ, described at the time of the Tasmanian Golden Jubilee in 1973 as the “Grand old man of radio”.

Tom Allen, VK7AL was our longest serving President, and H. M. (Chummy) Moorhouse secretary from 1933 to 1945.”

unveilingwiahonourroll.jpg (31078 bytes)7ZAX unveiling the honour roll

The honour roll’s purple shroud was then released and the roll officially presented to all present at the BBQ. We then moved into some amateur radio direction finding (fox-hunting) in the bushland of the Domain, much to the amusement of those bushwalkers and their dogs!

Hayden VK7HAY was our first winner and Steve, VK7XOR was our second winner. Certificates and prizes were given to Hayden and Steve. The home brew competition was then judged by Eric VK7TAS and Richard, VK7RO with Rex VK7MO taking out first prize (a 2m/70cm j-pole and certificate) with his 1296MHz septum feed, Bill, VK7AAW taking out runner-up with his 40m amplifier and Justin VK7TW taking out the encouragement award for his 70cm big wheel antenna.

The VK7 Advisory Committee then met for it’s inaugural meeting to discuss a number of matters from the implementation agreement.Goto Top of Page

The day finished up after this without a drop a rain falling, great friendships were renewed and some serious amateur radio fun was had by all.

Thanks to all involved in making this a fantastic day, it was a great team effort.

(73, Justin, VK7TW)

PS. The official parts of the day were videoed and will be shown at an ATV night soon. So if you missed it, stay tuned on a Wednesday night in the Hobart area.

Wednesday 1 November 2006 at 8pm

The Top Band and Much More

November 1st saw about 20 people attend the presentation called “The Top Band and Much Much More”. This were two presentations with the first being given by Dave, VK7DM. Dave started with a detailed explanation of his 160M AM valve transmitter. This was a design that used the best from the American and British designs and Dave designed and built it to broadcast specifications.

7DM_160M.jpg (55037 bytes)

Dave took us from the 6AM5 crystal oscillator in a modified pierce circuit through a 5763 driver and link coupled driving the power amplifier that uses an 813 beam power pentode which is capable of delivering 150watts AM continuously. The 813 is running 1000volts on the plate and 300 volts on the screen. The modulation transformer and a number of the modulation components were donated from Ron VK7ZRO.

Dave then ran through the construction techniques he used in the unit including getting the chassis electroplated in passivated zinc. The transmitter, modulator and power supply all mounts into a neat 19 inch rack.Goto Top of Page

7DM_Transmitting.jpg (108367 bytes)

Dave then went on to outline his 160m vertical complete with loading coil from a old Racal transmitter. Dave ran through the matching on the loading coil which is critical for this type of short vertical antenna and distributed a sheet of radiation pattern diagrams showing 160m radiation patterns for different types of 10m antennas.

Dave then handed over to Ron VK7ZRO who brought along his recently restored 1929 vintage tuned radio frequency receiver. Ron outlined the history of this unit from the original state along with pictures of the original unit. Ron rebuilt the entire including the reconstruction of the capacitors both fixed and variable. The only thing that is not original is the wiring which was originally 1/16 inch square copper wire. The receiver was definitely amateur in origin and Ron has recreated coils for 160, 80, 40 & 20m bands. The receiver uses a Philips A442 which was released in 1927/28 and the radio seems to follow the design of the Pilot Super Wasp of 1928 vintage.

P1010129sm.jpg (41978 bytes)

In Ron’s words it is a “beast” to operate with all elements of the receiver inter-reacting with the others so, there is constant adjustment required to tune a signal.

7ZRO_tuning.jpg (90169 bytes)Goto Top of Page

Ron installed the 160m coils and Dave fired up the transmitter into a dummy load and with a little tuning we were hearing AM signals on the 1929 receiver from the 2006 valve transmitter.

7ZRO_Demo.jpg (160542 bytes)

These presentations were video taped and we will also be playing these on an ATV night in the future.

Thanks to Dave and Ron for coming along and sharing their experiences with these fascinating pieces of equipment.

 

Saturday 21st & 22nd October 2006

Jamboree on the Air/Jamboree on the Internet 2006 Wrap-Up

We start with the report from the Blackmans Bay Scout hall from Rod, VK7TRF. A relatively quiet time was had by the operators at the Blackmans Bay Scout hall. Atmospherics gave us quite a bit of noise in the background to several of our H.F. contacts. Those contacts that we did make, reported much the same. The Canberra region gave us most of those contacts. 2 Metres allowed for some local activity and IRLP got us out farther a field.Goto Top of Page

jota2006_blackmans_bay.jpg (32619 bytes)(photo courtesy of Chris VK7FCDW)

However, while our contacts were down, they enabled us to get all that visited the Hall on air.

Several stations experienced the same as we did: It is certainly the younger ones that want to talk, those of High School age are relatively scarce at JOTA these days.

jota2006_blackmans_bay_2.jpg (27083 bytes)(photo courtesy of Chris VK7FCDW)

Thanks must go to those who helped man the controls: VK7's FTML, FDCW, HDS, and to those who helped with the rig/de-rig: VK7TPE and his mate John.

(Rod, VK7TRF)

Our second report comes in the way of a BIG Thank you from The Wellington District Commissioner on behalf of all her leaders and Scouts for an excellent week-end.

The use of your equipment and the operator’s time was very much appreciated.

The team at The Lea included: Roger VK7ARN, John VK7ZZ, Bruce VK7MBD, Scott VK7FREK, Christopher VK7FCDW, Graham VK7ZGK, Brian VK7HSB and Gavin VK7HGO.Goto Top of Page

jota2006_the_lea.jpg (27292 bytes)(photo courtesy of Chris VK7FCDW)

Thanks again guys see you next year.

(Gavin, VK7HGO, the Wellington JOTA coordinator)

Wednesday 4 October 2006 - 8pm

Men's Health - The inside line on men's health issues.

Promo:

Our “Ockertober” presentation is all about Men’s Health and the inside line on all the issues with Dr. Michael Boxhall. 

Yes….you know all the stuff you hear on the radio and television and never take any notice off HIHI.

All the stuff your partner, YL, XYL or mate tells you that you really should be taking seriously. This is really the talk for you!

The following is a summary of a document called “Wrestling the Tiger” and “The GP for He” by Laurie Bourke which can be found on the Health and Human Services website.

 “Men and their health have a relationship based on the 'need to know' principle.

A sudden death or a chronic illness that may have been preventable has far-reaching consequences for everyone.Goto Top of Page

The impact of the tragedy or the ongoing care that is required to look after someone with a debilitating chronic disease, have huge ramifications for the welfare and lifestyle of the individual and their family.

Former Premier Jim Bacon's story is one example of this impact, and so is that of every other Tasmanian man who dies prematurely from preventable causes.

Most men avoid their GP like the plague - only turning up to see their doctor when they are virtually at death's door.

Men often put off a visit to their GP because they are too busy, because they don’t think their condition warrants it, or because they might be seen as “less of a man” if they complain about their ailments.

The danger is that when it comes to health - like most of the good things in life – we sometimes don’t appreciate what we have until it is gone.”

Our talk on the 4th of October at 8pm is by Dr. Michael Boxhall who is a GP at the Cascade Rd Medical Practice and he has seen and heard it all and I have no doubt is frustrated like most GPs that they only see men at their worst – when they are really sick!

Don’t be shy come along and hear what it’s all about. If you don’t come along for yourself then come along for the XYL and you can then say you now know it all!!Goto Top of Page

Report:

The night saw about 15 people hear a very interesting and helpful talk by Dr. Michael Boxhall on a broad range of men’s health issues.

And yes, Michael did not beat around the bush….straight into the problems with the prostate, what’s it all about, prevention, symptoms, etc complete with illustrations! Michael went through the treatments and I think most people had tears in their eyes after that HIHI.

Michael then covered prostate cancer, symptoms and treatments then rose to the occasion, as they say, and talked about erection problems and, yes, there were the obligatory questions about Viagra.

Dr. Michael then covered bowel cancer, kidney stones, diabetes and finished off with osteoporosis and joint problems, etc.

There were many questions asked and myths dispelled and we got into the details of men’s health with Michael even giving us a demonstration at one point.

I have recorded the presentation and we will hopefully play this in a future ATV broadcast for those who missed the session.Goto Top of Page

Thanks to Michael for giving us his time.

73, Justin, VK7TW

Wednesday 6 September 2006

8:00pm (20:00)

Modern Computer Controlled Process Electronics

Dale, VK7DG took a group of REAST members and friends for a detailed tour of the National Foods milk processing facility in Lenah Valley.

I start this outline of what we saw with the comment, I was and I think I speak for the group, blown away by the amount of technology used throughout all areas of the plant. We were equally blown-away by the amount of knowledge and experience Dale has with all this advanced process electronics and computing control!

We started funnily enough at the start, where the milk comes in via the tankers. All through the plant there is a complex network of food quality stainless steel pipe-work. Even the electrics and control lines are routed around the plant in stainless pipe!Goto Top of Page

In the loading dock there is a LCD touch screen and all control is done via the screen, even down to turning the mercury vapour lights on. All monitoring is done via the panel, tank levels, flow-rates, etc. There are interlocks on everything so it is impossible to connect the wrong things or open valves that shouldn’t be. The “block & bleed” valves are intelligent in that they are connected via a two wire “proffy” buss system back to networked node controllers which are all around the facility and all connected via networks. The valves report back to the controller what they are doing and when they have completed the operation and if there is a problem they report what the problem is. The valves are either 24VDC or pneumatically operated and cost about $4,500 each! Mind boggling when you consider there are matrices of these valves under the three 95K litre tanks to feed the raw milk around the plant and another partially built matrix in the processed milk area.

Hot water for cleaning and chilled water is fed around the facility and cools the milk down to about 3degrees whilst it is in the plant. Most monitoring devices like flow-rate meters, conductivity, temperature, butter-fat content monitors, level meters, etc all operate on the industry standard 4-20mA interfaces. This makes them less susceptible to voltage changes, spikes, etc. These interfaces are then converted to digital and fed back to programmable logic controllers which feed back into the main control systems.

There is a cleansing and cleaning system throughout the plant that cleans using industry standard caustic sodium hydroxide, Peracetic and nitric acid solutions dependent on what they are cleaning. Conductivity measurements ensure that pipes are fully flushed prior to running food product through and the flushing process is fully automated. The cleaners are filtered and recycled.

Within the plant Dale explained the various processing stages like the homogenizer that uses high pressure (150bar) to pulverize the fat in the milk. The pasteurization processes that heats the milk to 78 degrees for 30 seconds to kill bacteria. In this area is also the separator to extract the cream from the milk and complex mixing valves and monitoring sensors to reduce or raise the fat content of the milk using permeates. The butter-fat content sensor alone costs $6000 and works on light passing through the milk. Heat recovery is also used throughout the plant to reduce the energy usage.Goto Top of Page

All sensors and valves are controlled using a Siemens SCADA system and the processing lines and plant floor is graphically represented on the LCD screen and any number of sensor readings and process related measurements are displayed on the PC and yes the PC was running XP. Dale proudly showed us the main processing module which is in a fully air conditioned and monitored environment.

We then moved into the packaging area and inspected a new carton packaging line that is fully automated and again contains a mass of sensors, touch screens and some interesting use of fibre optics to sense and adjust for the carton stock. We moved to the bottle filling machines and the final crating machines that load 13-14 crates per minutes and we could get an understanding why there were cages around this machine!

Dale then took us through the refrigeration plant and showed us power engineering at its best. There were four large compressors that were all electronically controlled using three phase 150A SCR/Triac controllers and associated PLCs and electronics. Most of the monitoring panels were saying 400V at 75A, now that’s serious power! The refrigeration uses both ammonium and glycol systems. The last stop was the boiler house and this is definitely the place to be in winter HIHI. Again everything is electronically controlled in the boiler house with two unattended boiler supplying 45K litres of hot water at 95degrees for the plant.

I think we all came away very impressed with the stat-of-the-art technology employed in this plant and Dale’s vast knowledge and skill with it.

Thanks a million  Dale for taking the time to show us through.

Goto Top of Page73, Justin, VK7TW

Wednesday 2 August 2006

Optimised Radio - Contesting and DXing

Martin VK7GN, our very own resident hardcore contester and DX operator give us an illustrated powerpoint presentation called Optimised Radio – Contesting and Dxing from a Portable Location.

The session included info on operating both portable and from a base. The session also included a detailed explanation of the High Frequency Terrain Assessment (HFTA) program written by N6BV and Martin explained and demonstrated using the program why good HF operation is all about Location, Location, Location, whether you are a portable or fixed station.

vk7gn_HFTA.jpg (66127 bytes)

vk7gn_HFTA_b.jpg (82012 bytes)

Martin took us through the development of contests through field days and activity times and related the different types of amateur operators who operate contests. From the pro-contester, clubman contester, award hunter and just the participant. Martin related what sets a pro-contester apart from other contesters and outlined that your score in a contest is proportion to BIC “bum-in-chair”!Goto Top of Page

vk7gn_portable_operation.jpg (69168 bytes)Yeah right!

Always operate like a pro-contester and Martin took us through some of those techniques and an important one for any contest was learn to live with QRM. The essentials to increase your score through higher BIC are 1). Comfort 2). Ergonomics 3). Antenna and Location and 4). Your equipment and the key in the equipment department was spend the money on a good receiver, you can always operate with just an adequate transmitter but, a great receiver is what you need to hear those stations between the QRM!

vk7gn_speech_processor.jpg (101869 bytes)Extreme Speech Processors!

Martin related his vast amount of knowledge and experience that has only been built up through years of HF operation and I am very appreciative that Martin is willing to share this knowledge with us.

Thanks Martin.

Goto Top of Page73, Justin, VK7TW

Wednesday 5 July 2006, 8pm

Communication at 474 terahertz*

This was a great night demonstrating what electronics and optical experimentation is all about. About 20 people enjoyed a demonstration and talk by Mike Groth VK7MJ. Mike has been experimenting with optical communications methods for over 40 years along with Chris Long from VK3.

Mike and Chris Long set the Australian duplex optical communications record on 19 February 2005 from Mt Wellington to Mt Barrow (167.7km). Mike has been working on the new transceiver and will be demonstrating it on the night and running through the theory and practice of optical communications.

vk7mj_with_tranceiver_outside.jpg (46921 bytes)Goto Top of Page

The first part of the evening was a demonstration of Mike’s new transceiver from the Domain to Reg VK7KK who was on Mt Rumney with one of Mike’s other transceivers. In fact the one that set the record between Mt Wellington and Mt Barrow.

vk7mj_with_tranceiver_front.jpg (127830 bytes)

Mike pointed out that optical communications is the oldest form of wireless telephony and is 126 years old and was first patented by Alexander Graham Bell as the photo-phone. The military took some interest early in the 20th Century however current modulation of carbon arcs only got them about 8 miles!

vk7mj_with_tranceiver_VK7TAS.jpg (96142 bytes) Eric, VK7TAS talking with Reg VK7KK via the photo-phone

The transmitter uses a 3w luxeon LED which has greater intensity than a quartz globe. The luxeon draws 1.4A at about 2.5V and only dissipates 1 watt. The modulation peaks the current at 2.2A. The red Luxeon is about 630nM which equates to 474THz.

vk7mj_with_tranceiver_side.jpg (45350 bytes)

Transmitter modulation is straight DC applied to the Luxeon via current limiting resistors (4 x 27 ohm) which is modulated with the audio voltage.

vk7mj_with_tranceiver_inside.jpg (168959 bytes)Goto Top of Page

The Fresnel lenses are the flexible vinyl inexpensive book reading type of lens that are available from a range of sources including the blind society and even Book city! These are glued to a piece of glass with 5minute epoxy which is mounted in the box. Remembering that the lens is always with the light entering from the convex to the planar side and this is the same with the Fresnel lens. A layer of black tape around the outside finishing the lens module off.

Mike even went into the internal construction of the LEDs and why certain types are better for optical communications.

Another hint is the transmitter beam is wider than the receiver beam (0.5 degree) to assist alignment with the other station. The ratio of the size of the source to the focal length gives the beam width and you need to get the maximum intensity of light in the beam. Mike and Chris have found that the best arrangement is a focal length of 1-2 times the lens diameter. The size of the transmit lens does matter, it doesn’t change the intensity but a bigger lens does average out the flutter caused by scintillation. To assist the alignment of the transceivers Mike suggests that you place the detector/ photodiode into a larger tube with a small lens on the outside that acts as a magnifying glass and you use align the light from the other transceiver through the tube until it disappears behind the detector.

Mike has constructed a new transceiver with Fresnel lenses of approximately 300mm square. The box construction is plywood and the electronics uses commonly available components and Mike took us through the design in some detail.Goto Top of Page

vk7mj_with_tranceiver.jpg (26996 bytes)

The detector preamp needs to be a high impedance, very low current FET input of either opamp or discrete junction type. For example a basic MPF102 will work. Fed that into BC559 GP bipolar transistor into an emitter follower acting as a current mirror feeding back into the detector diode to put some back bias on the photodiode. This is similar to an opamp and is very low noise. This is then fed into a headphone amplifier with switchable gain up to about 500 and/or a low impedance output amplifier into a speaker. This arrangement is AC coupled which overcomes background light/noise levels ie. a moonlit night. This has a flat response up to 30kHz. Mike has built into his circuit switchable narrow and wide bandwidth detector responses. We are only talking 20-40 pico-amps coming from the detectors.

vk7mj_with_tranceiver_inside_theory.jpg (177770 bytes)

To align the detector all you need is a light source and you adjust the detector diode for maximum noise. Then to align the transmitter all you need is a wall that is couple of hundred metres away and you align the transmit beam to give you maximum signal with a suitable offset. There is some trial and error to get the offset correct. The transceivers will run in the daylight however the noise levels are higher and you need baffling around the transmitter/detector to prevent background light getting into the detector.Goto Top of Page

Every time you double the distance you lose 6dB and this assumes perfectly clean air which it isn’t. Dependent where you are the transmission losses through the air equates to between 0.6 and 1dB per kilometre. This varies dependent on whether is has just rained, etc. Mike suggested that the path loss between the Domain and Mt Rumney would be in the order of 0.1-0.2dB per kilometre considering it had just rained and was a clear night. The record between Mt Wellington and Mt Barrow Mike and Chris worked out there was about 15-20dB path loss. If there is smoke or moisture in the air then the losses are much higher.

The original record for one way speech using a 300mW laser through telescopes was set in 1964 over 118miles. They drove the laser with a 10W AM transmitter!

Experience has taught that lasers are not the way to go due to atmospheric absorption. Two problems – 1. Convergence means that beams width are small and therefore you have problems aiming it and 2. The small beam width also causes scintillation from turbulence in the atmosphere causing the coherent wavefronts to not reach the destination at the same time causing phase distortions therefore the light appears to scintillate or selectively fade.

The question was asked are their longer paths available and Mike pointed out that the issue is the earth’s curvature which goes up as the square of the distance. For example to get across Bass Strait there would need to be an extra 200-300 metres at each end to be able to see across the Strait and not graze the water.

A few words of warning – do not look into aGoto Top of Page Luxeon LED it is VERY bright. You also need a flap on the front of the Fresnel lenses. If you point these lenses into the sun it will cook the detector and LED and probably set fire to the wood! Just ask Chris Long he has experienced this!!!

Mike’s key message was simplicity in this application is the best which makes it great for experimenters!

Thanks to Mike for giving us the time and vast experience with this fascinating subject.

73, Justin, VK7TW

(* 474 THz = red light)

Saturday 3 June & Sunday 4 June 2006

REAST FIELD WEEKEND

The REAST Field Weekend was held at The Lea Scout Camp. The weekend focused on portable/mobile operation and the theory and practicalities of this exciting mode of amateur radio.

We started the weekend with some great hands-on knowledge and experience shared about antennas, rigs, rope work, (and getting things stuck in trees, HIHI). Rod, VK7TRF and Martin brought along an extensive range of poles and elevation methods and talked through them. We did manage to get the G5RV high in the air after a few goes!

Masts_Hanging_Antennas.jpg (35740 bytes)VK7GN relating his antenna hanging experiences.

After lunch we headed into the theory and practicalities of Amateur Radio Direction Finding (ARDF). We built four tape measure yagis and went through attenuator designs including Richard VK7RO's dry grass method using body absorption. The fox took off a few times and tried to fool those intrepid fox hunters however, it was found everytime!

ARDF_Antenna_Assembly.jpg (72337 bytes)Foundation Licensees assembling the tape measure yagis.Goto Top of Page

The next session on Saturday was given by Rex VK7MO on Digital DXing. This illustrated session demonstrated that you can operate up to approximately 2000km with VHF and a relatively simple setup using the new digital modes. Rex went through the EME, Meteor scatter and SSB modes. After a coffee Martin, VK7GN gave us an illustrated talk on contesting and HF DX operation. For those who are not aware Martin is a hard-core contester and DXer and he relayed a wealth of knowledge about contesting and operating HF. A BBQ tea was enjoyed, the open fire stoked and some archival films from the 1940 played on the big screen - Radio at War was particularly rousing with it soundtrack and mysterious enemy that the Army & Navy were fighting!

Rex_Digital_Talk.jpg (22914 bytes)VK7MO talking about Digital DX

On the Sunday morning the National and Local broadcasts emanated from the field weekend then it was off in convey for a BPL tour of Mt Nelson. About 15 people were treated to BPL - up close and personal. Starting from the first injection point we moved up to the top of the bends then around to the areas around the shop where notching is evident. This gave people a visual and audible look at the BPL trial along with a demonstration of FSM software developed by Owen Duffy VK1OD. It was then back to The Lea for Lunch.

BPL_up_close_and_Personal.jpg (153033 bytes)BPL - Up close and personal!

Ian_Broadcast.jpg (29794 bytes)VK7IR reading the Regional Broadcast.Goto Top of Page

Brian VK7BW gave a great session on connectors, coax striping, connector crimping, and standard low voltage power wiring that has been developed within the WICEN group. Danny, VK7HDM & Scott, VK7HSE then gave a hands-on talk and a practical demonstration of APRS equipment and software. Scott went for a drive around The Lea and was watched on the map as his journey progressed. We finished up with a talk by Roger 7HRW on professional on-air operation. Roger related his vast skill and knowledge of radio operation from his many years with the Tasmanian Ambulance Service.

Brian_Connectors.jpg (28084 bytes)7BW on all things connectors.

APRS_Expectancy.jpg (28038 bytes)Group APRS watching the map!

Roger_Operations.jpg (16075 bytes)Roger with on-air operation.

All up about 30 people enjoyed the weekend including many current and soon-to-be Foundation Licensees. Most sessions were taped with video so we can run them at the ATV and Wednesday afternoon sessions. There are also some still pictures available on the REAST website.Goto Top of Page

Thanks to all people who were involved in the weekend, it was a great success and something for the committee to look at again for next year or maybe even sooner!

Draft PROGRAM of activities.

(Justin, VK7TW)

Wednesday 24 May  2006 - 7:30pm

Military Signals and More!

REAST’s May visit was last Wednesday night the 24th of May and was a visit to the Military Museum of Tasmania at Anglesea Barracks.

About 25 members, friends and XYLs came along for a very informative night from our two guides – Lt Col. David John (Ret), VK7DJ from the Royal Engineers and Lt Col. Owen Winter (Ret) from the Signal Corp.

MMTOWGroup.jpg (27250 bytes)Lt Col Owen Winter (Ret) in Green Coat and tour group

The museum is in the original heritage sandstone Barracks Military prison and was built in 1846 and was designed by Lt Col Victor and the façade of the building is a blend of Romanesque and Grecian influences. The interior is double storeyed with six cells on each tier and built in goaler’s quarters.

The building has been used for many different functions starting as a goal, then being used as the Hobart Girls Reformatory, Army personnel department, volunteer military forces leading up to the 1878 Defense Act. The goal was based on the Pentonville Model Prison (1842) and are similar to the model prison found at Port Arthur. It had pipe warm air from a furnace and each cell had running water which is still evident today.Goto Top of Page

Each cell has been setup as a different aspect of Tasmanian military history ranging from the 1804 original “Red Coated” British Army forces that came with Lt Governor David Collins through the Boer War into the Great War, WWII, Vietnam up to the modern day peace-keeping forces. The current feature exhibition is on the Korean war.

MMTRedCoat1829.jpg (17448 bytes)1829 British Foot Soldier

There are a number of pictures available on the website of the visit and David, VK7DJ, our guide can be seen at the gun emplacement in the Korea exhibition.

MMTKorea7DJ.jpg (20109 bytes)Lt Col David Johns (Ret), VK7DJ demonstrating in the Korean Exhibition

MMTKorea7DJGroup.jpg (20845 bytes)L to R - Peter VK7TPE, David VK7DJ, Gary VK7JGD and Stu VK7NXX.

There is a room dedicated to signals from the heliograph (sun & mirrors) used in the Boer War through to the sets used within the Vietnam conflict. The replica of “Winnie the War Winner” built by Barry, VK7RS is on display along with flag signaling, signaling lamps from different eras, a 101 set, antennas, through to VHF radios used in Vietnam.Goto Top of Page

MMTHeliograph.jpg (27331 bytes)Heliograph and signaling flags and lamps

WinnetheWarWinner.jpg (84301 bytes)Winnie the War Winner replica

MMT101set.jpg (21198 bytes)101 set

One particular area of interest was the WWII covert operations room which featured a disguised UHF (yes ultra high frequency) transceiver which looked like a water bottle and could be used for short range comms to aircraft.

MMTUHFCovertOpsTcver.jpg (19381 bytes)UHF Covert Ops Transceivers

This is a fascinating place and if you missed the tour then the museum is open each Tuesday and is well worth a visit. It is a real credit to David, Owen and museum staff.Goto Top of Page

Thanks to David and Owen for giving us their time and showing us through.

Wednesday 5 April  2006

Antarctic Adventure - Ben Tucker, VK7FSNP

We had 23 people along to our presentation night including visitors Jim, N9GFT/VK4GFT and XYL Anne and Di VK7ACW who is XYL of Mike VK7ACQ.

The illustrated presentation was given by Ben Tucker, VK7FSNP about his trip down to Antarctica in the 34 foot vessel Snow Petrel. Ben outlined that sailing down to the frozen continent has always been a dream and three years of preparation saw it all happen before Christmas 2005. His crew was his younger brother Matt and father Jon.

vk7fsnp-A.jpg (59981 bytes)

Ben emphasised the massive amount of preparation that was undertaken not only on the boat to strengthen and prepare it but, also the supplies, safety and backup equipment. Ben estimated there was 2 tonnes of supplies on board for the 6 week journey! The distance is 1500 nautical miles one way.

vk7fsnp-C.jpg (33101 bytes)Goto Top of Page

They sailed due South and reached Commonwealth Bay and Cape Denison and sat out the catabatic storms off the ice of greater than 60 knot winds. Fortunately they had 5 shorelines and one anchor to stop the boat going anywhere in these conditions. They then sailed onto the French base at Dumont D’Urville and the hospitality was incredible.

vk7fsnp.jpg (27734 bytes)

Ben "in the shack" on board the Snow Petrel.

The technology used was HF transmitted and received weather faxes on computer. Regular skeds with Mike, VK7ACQ on marine 4, 6 & 8MHz frequencies and the 40m amateur band. An interesting observation was that the solar panels work much more efficiently in the cold and they had 22 hours of daylight to charge the batteries. The safety equipment included two dingys, four EPIRBs on two different frequencies, survival suits for each member of the crew and an iridium sat phone.

vk7fsnp-B.jpg (33653 bytes)

Ben’s brother Matt took video and we were luck enough to see a teaser of the film he is currently putting together and it looks fantastic.

This was a very inspirational and fascinating presentation by a young guy with a goal and is a classic example of an ordinary person doing extraordinary things.

Thanks Ben, it was great.Goto Top of Page

BenTuckerMerc20060318.jpg (108130 bytes)

The Saturday Mercury Article 19/03/06 on trip

Wednesday 1 March 2006

Lightning and Lightning Protection

Remember this a few weeks ago?

Lightening_Nth_Hobart_20060120.jpg (26396 bytes)
Taken from North Hobart 20 Jan 2006

It was great to see about 30 people along to this talk and we had a number of visitors including Ed W0SD and XYL Edith from South Dakota who were guests of Martin, VK7GN, also there was Wally, VK5TW, OM of VK7TW and Joe, VK7JG down from the North. 

7ssA.jpg (69406 bytes)

Phil Tompson, VK7SS from Novaris gave us a detailed illustrated talk on all aspects of what lightning is, its effects, the analysis of strikes on structures, the relevant standards and the models used to simulate a strike.Goto Top of Page

7ssB.jpg (53489 bytes)

There are frightening levels of current and voltage that nature unleashes in a fraction of a second. Phil then went into all the aspects of providing lightning protection of the structure, powerlines and equipment connected to the powerlines. Phil covered the different types of surge protection and the strategy for employing these devices at a site.

7ssC.jpg (62065 bytes)

Some of the pictures of lightning strikes and the damage it makes were VERY impressive.

Thanks to Phil for giving up his time to give us a talk and it was great to see so many amateurs along.

Sunday 5 February 2006

REAST 2006 Annual General Meeting Report

This year's REAST AGM could stand for All Goes Magnificently.Goto Top of Page

A great turnout with over one third of members attending and with membership applications submitted on the day taking membership past the one hundred mark.

REAST_AGM_2006.jpg (39492 bytes)

Tom Andrews who recently completed his Foundation licence and soon to become VK7TAA - a fitting call for this friendly guy, obviously going places who became REAST member number one hundred.

And we have a member number one hundred and one our long standing HF CB rebroadcaster Damien VK7HDS.

One member, not known for his happiness with matters administrative or political said it was the most positive AGM he had been to.

And another rare positive we had more nominations for Committee positions than there are positions.

A unanimous vote directed the Committee to find a way round the rules to enable all nominees to be appointed.

Dale VK7DG - our Hon Sec of seven years decided it was time to take a break and our quill pusher is now

Ben VK7FBCS who joinsGoto Top of Page

Justin VK7TW - President

Vice President - Clayton VK7ZCR

Treasurer - Roger VK7ARN

and Committee members

Brian VK7HSB and Rod VK7TRF

The agenda for the first Committee meeting has already grown to a marathon indicating a busy year of growth ahead.

The mix of new and old blood in terms of experience and age provides the profile suited to our future membership.

All ex-officio position holders were happy to continue in their roles providing us with continuity and assurance of their expertise for the coming year.

Following the close of the meeting, Rex VK7MO gave us an interesting update on his current experiments. Rex's enthusiasm for his specialty shone through more brightly than the focus of his signals.

7MOTalk_REAST_AGM_2006.jpg (38554 bytes)

The next stage in the proceedings was the auction of two pieces of generously donated as new Hi-Fi equipment.

The day concluded with a barbeque in perfect weather.

Overall - perfect outcomes all round.Goto Top of Page

(Roger, VK7ARN)

28-29 January 2006

January Foundation Licence Course

REAST's January Foundation Training and Examination Session was held last weekend with 8 participants gaining their Foundation Licence. Included were 3 school students with 12 year old Sam our youngest Foundation success.

REAST_2nd_Foundation_Licence_Course.jpg (54867 bytes)

Thanks to all who assisted in this activity.

Foundation Licence Manuals and CD's are available for purchase from McCann's Model World in Elizabeth.St. Thanks Barry for making this service available.

Contact Reg Emmett VK7KK on 0417 391 607 for more information or to book for the next course.

(Reg, VK7KK)

2007

Events/Meetings/Gatherings in 2007

2005

Events/Meetings/Gatherings in 2005

Nov & Dec 2004

Events & Meetings in Nov & Dec 2004

 


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