Saturday, 9 July 2016
Peter VK3PF the Conference convener welcomed everyone and reminded them that the WIA bestowed many awards on people who are regulars to the conference.
Dale VK1DSH – GA Taylor Medal, David VK2JDS – Ron Wilkinson Award, David VK3QM and Lou VK3ALB – Technical Excellence Award and Ron VK3AFW received a President’s Commendation.
We remembered friends who were no longer with us – VK1WJ, VK1VP, VK3UM
David VK5KK started the presentations with an excellent expose on his VHF and microwave SDR adventure.
He started with his experiments with the mCHF from M0NKA which is a KX3 equivalent and used this HF SDR transceiver to drive the UHFSDR by WB6CGR.
David used the SDR2GO software with the WB6CGR board. David also experimented with the STM-32-SDR and SDR2GO software but shelved as other options became available. David uses a DDS as a VFO with a optical step encoder with 600 steps. David claims he gets 2-4dB better SNR on an SDR than an FT-817.
The mcHF is still in development out of Germany and uses the I/Q signals into NAP65.
This is primarily sad a User Interface for the UHF SDR board. He uses external DDS – from Minikits (si570PLL) or the PLL boards from VK3XDK. You do need 144/432 helical filters for block filtering and uses a Mitsubishi module for a 2.5W PA from Minikits. The DDS is a AD9951 up to 160MHz and uses the 2 phase shifted outputs to double up to 288MHz for 144MHz SDR.
There was some noise from the user interface and needs a shield between the PCB and shielding the CPU. Sequencing was done in software through UI libraries available. Another SDR was the Russian Tulip SDR – all in Russian! David also mentioned G0ORX and the piHPSDR available from GitHUB. PI3 using Hermes board. Definitely follow-up on that one!
LimeSDR is the next BIG thing – US$289.00!! about AU$400 and this is a game changer for us and will enable microwave operations as an SDR. The next generation apparently goes to 10GHz!
The next presentation was by Alan VK3XPD for the Microwave Enthusiasts Award which went to Doug Friend VK4OE.
Very impressive glass engraved plaque that lights up!
The next presentation was by Joe VK3YSP and Julie VK3FOWL and was on the Schools Amateur Radio Club Net activity on ANZAC day with the SARCNet school kids, scouts and volunteers. This event included a high altitude balloon launch and Joe and Julie took us though the technical aspects and the colour and movement they have added to make a balloon launch appealing to primary school kids. This included the ability for the kids to track the balloon on their smartphones via the web.
The SARCNet has a website – SARCnet.org.au and has been setup to inspire primary school age kids who are at an age where they must differentiate from parents and peer group – the ANZAC day celebration provided a great day of combined activities to showcase amateur radio.
The schools program also run a grade 5 elective for soldering where they build a LED flasher kit which goes into owls eyes. There is Morse Code, First Aid – CPR Course, the High altitude balloon launch. There was also ARDF on the day. Murray Taylor VK3MJT helped with the Scout side.
They demonstrated the colour and movement of the HAB launch including strobe – beeper and count down!
There were over 300 HABS around the world – huge event. The balloon regs currently allow up to 50grams with no approval BUT the law is changing on Sept 29.
Joe used an interesting techniques of working the PSK numbers out on a spreadsheet for the function to create the lookups table in the Arduino that was used to transmit the PSK. Joe then went through the process of uploading the data on the notebook into the HABHUB website for tracking using DLFLDigi
The story will be in the August Issue of AR has the Anzac Day event
The next talk that Joe and Julie did was the AIS Saves Lives presentation. This is the automatic identification system on ships around the world.
There are many AIS black spots and amateurs can help to fill the black spots – on 162MHz and is easily decoded and uploaded to the 5 websites that display this information. All Class A vessels over 300tonnes are required to have AIS and it’s optional for class B below 300 tonnes.
You can use a cheap RTL SDR and even an early RaspberryPi version will work and it can be stand alone. Need to calibrate it using the local Cell tower 900MHz signal but this is easy to do using some Linux programs. (Linus – Kal -2 GSM900, Kal -c 15, RTL AIS software)
The next presentation was by Glenn VK1XX on the next generation of semiconductors that are hitting the market – Gallium Nitride and Silicon Carbon devices.
These devices have very low capacitance and therefore are excellent for microwave frequencies and the SiCs have high breakdown voltages and high power levels and can run hotter than most silicon and germanium devices.
The SiC are high voltage – 1200-1700V 100A on resistance of 50milliohms!
The current LDMOS will be around for a while but will be soon overrun by the GaN and SiC – the devices are Broadband = no capacitance = less matching required and are more efficient and therefore less heat sinking for equivalent power levels. These are Game Changers in the high power microwave space
The next talk was by Roger VK2ZRH about where regulation is going. Roger started by mentioning that VK amateur numbers have actually increased from 14035 in 2014 to 14144 in 2015 whereas in Germany and Canada they have dropped. There is SIGNIFICANT change ahead for the industry, Technological Change is upon us and demand for the spectrum is increasing incredibly.
The WIA’s position is we cannot go backwards with conditions, bands, modes, etc as they start the negotiation.
The Q&A afterwards showed the need for Digital Modes for Foundation licensees, that the Curriculum will need to change and the WIA is waiting on ACMA/Act Review results, Regulation will go to the industry in the new world order, Power assessments are SAR based – Technical standard needs work – ARPANSA sets this and the regulator is responsible for setting the standard, Global EME band plans are not aligned – IARU pushing the relevant regulators in each country, ACMA wants to make their life easier therefore functionality will Probably come to WIA, Amateur service is competing for spectrum along with all the other users that need spectrum and 5G is coming along with IOT, etc. Bill for the new act is out there and ACMA digesting – caretaker has stopped progress. Watch this space!
Great lunch as usual!
The first afternoon presentation was David Rowe VK5DGR on his open source – SM-2000 VHF SDR with embedded FreeDV. David showed the evolution of the SM-1000 an then the development and progress on the VHF SDR radio – SM-2000.
He was accompanied by Brady KC9TPA from the US who has been helping David with development. There was a demonstration of the latest FreeDV modes and SSB signal in dodgy conditions and then the fully digital chained SDR and the results were remarkable from 3/1 to 5/9.
David passed around the SM-2000 PCB and it is a great development board with the discrete RF and radio blocks accessible and understandable. These boards, circuitry and software are all open source – great work David! There was a plea from David for more people to get involved with the team and actually help with different aspects of the project. This presentation was videoed and is available with last Year’s FreeDV video.
Joe VK3YSP and Julie VK7FOWL then did a presentation on a. Homebrew Speech synthesiser for the FT-817
Joe took that audience through the process of using the Arduino and voice synthesis chipo to take the various settings on the FT817 the voice used was the British female voice nicknamed Rachel. Enough Said!
The next presentation was by Glenn VK1XX on the near effects of ground on your field day setup or repeater site.
Glenn took us through the theory of Fresnel zones, wavefront and Ray diagrams and the different diffraction patterns
The key principle demonstrated was the Knife edge diffraction attenuation through the blocking of the various fresnel zones.
Glenn applied this knowledge to Rex’s 10GHz operation and concluded that on flat ground Rex really needs to be on top of his vehicle to improve performance!
For field day operation with a tower and 6/2/70cm Yagis it would actually be better to put the 6m yagi on the top of the tower to clear the fresnel zones unless on a cliff or steep sloping ground.
The last presentation for the day was Tim VK5ZT with his alternate 3.4GHz Panel mods
These panels have been made popular by the Geelong ARC and Tim has improved on the modifications and simplified them.
VK5ZT mod doesn’t require as much mod as GARC. Tim also reprograms the Microcontroller ATMega with the help of VK3HZ who disassembled the code. Tim uses an Arduino Nano to the ISP port to the on board ATMEga to reprogram the on board ATMEga8 – use io pin 10 for reset to the on board atmega8.
Tim finished up with the faults and issue with the boards that he has seen – Yellow boards worse than green versions – be careful.
Gippstech Dinner – Morwell Club
Rex VK7MO presented about QRP EME on 10GHz
Rex took us through the intricacies of his tests with Charlie G3WDG and the EME low liberation path which enabled them to drop the power to 5W between the 77cm and 3m dishes. Rex then used a neat feature in WSJT which allows you to introduce random noise that degrades the SNR to test what level you would be able to receive the signal at and Rex estimates that it would be in the order of 2W when moon liberation is low.
Julie VK3FOWL and Joe VK3YSP – az-el satellite antenna rotator
Joe and Julie took us through the project they built for an az-el portable satellite antenna mount.
Joe took us through using an $11 accelerometer as a gravity meter, etc module with an Arduino which is mounted on the boom to calculate convert the position to Az-El and that enable you to feed the positioning servos with power to position the boom of the arrow 2/70cm satellite antenna at the satellite and track it through the sky. Joe uses GPredict on Linux to drive it and the Hamlib Libraries. Joe took us through the mechanical challenges and the operation.
Roger Harrison VK2ZRH – Norfolk Island microwave jaunt
Roger took us though a pictorial collage of the 3.4GHz microwave activity on Norfolk Island during the WIA AGM weekend using the GARC modified 3.4GHz panels.
Dale Hughes VK1 DSH – Arduino SSTV TX/RX
Dale took us through his project to build Arduino Robot20 SSTV transmitter and receiver using Arduinos. He related some of the coding issues he had and some interesting solutions like self aware adjusted timing to ensure the horizontal sync was in the right place. Dale promoted this project as a possible advanced STEM project to introduce students to TV technology.
Rex VK7MO – Update on WSJTX
Rex gave us a look at the latest version of WSJTX and its performance improvements and some of the great built in features of the program – system performance testing, and being able to predict how little power would be needed for a contact. And even some nice programming Easter eggs that Joe Taylor K1JT has included in the program.
Dave Hardy VK2JDH Android phone controlled Arduino via Bluetooth
Dave showed how to use an online tool to built Arduino based control code that can be down loaded to an Arduino and controlled via android webpage controls via Bluetooth. Dave originally used this for controlling and monitoring an Engel fridge in the car and thought this has application for amateur radio and demonstrated the control of an IC706 via the CI-V port. This has some great AR applications and is easy to use.
Three themes were prevalent at Gippstech 2016 – Software Defined Radios, Arduino controllers and Coding – we are seeing the predicted transition from soldering to programming for homebrewing!!!
Raffle – I was lucky enough to win two prizes!
We had our traditional Pizza lunch and then back to Tullamarine to fly home, thanks to Rex our wonderful driver!
73, Justin, VK7TW