Author Archives: VK5GR

Adelaide CBD 70cm Repeater returns to service! (UPDATE)

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After several years off air and/or operating from a temporary site in the western suburbs, the Amateur Radio Experimenter’s Group is please to announce that we have been able to negotiate a new home for the club’s VK5RSA Adelaide CBD 70cm repeater!

AREG has entered into a sponsorship agreement with KernWi-Fi, who are supporting the club by facilitating access to one of the premier communications sites in the Adelaide CBD atop Westpac House. At 134m high, this site is on one of the highest buildings in the city! AREG wishes to express it’s sincere thanks to Phil Kern (VK5ZEY) for his support of the VK5RSA repeater. It has been a dream of the club to gain access to the site for nearly 20 years and it is great to see it finally come to fruition.

The repeater itself has been rebuilt by Paul VK5BX & Dean VK5HMV, and was installed by Dean VK5HMV and Shane VK5NRV over this past weekend. This was the culmination of 9 months of discussions and planning by the AREG Committee, members on the repeater sub-group and the KernWi-Fi team.

 

VK5RSA operates on

438.025MHz (-7MHz input)

with 91.5Hz  CTCSS

 

NOTE: The repeater input frequency was changed Monday night due to un-resolvable interference from the co-sited commercial operators. VK5RSA is now operating according to the new 70cm band plan, with a repeater receive frequency of 431.025MHz. This is a -7MHz offset instead of the old -5MHz offset that was in use previously.

But Wait – there’s more!

In addition to being installed atop one of the highest buildings in Adelaide, VK5RSA is now part of something much bigger. It has now joined the growing Central South Australian repeater network, which provides coverage over most of central SA.

The repeaters in the network are:

Location / AreaCallsignOutputInputCTCSS
Adelaide CBDVK5RSA438.025MHz-7MHz91.5Hz
Adelaide RegionVK5RAD439.925MHz-5MHz
Adelaide NEVK5RKW438.050MHz-7MHz
Lobethal / Adelaide HillsVK5RAH146.775MHz-600kHz
Mt Bevor / Murray BridgeVK5RMB146.875MHz-600kHz
Victor HarborVK5RVH147.100MHz-1.6MHz
WaikerieVK5RWR146.750MHz-600kHz91.5Hz

NOTE: With the network access comes a change in mind set for operators too. For all 6 repeaters to operate together, it is important for users to leave at least a 1 second gap after the repeater tails before transmitting. This will give sufficient time so that all of the transmitters and receivers can sequence correctly thus preventing one or more repeaters from being locked out.

The nominal best areas to access each repeater are shown here:

Strongest Serving Repeater Map (Note Victor Harbor not shown)

The coverage of the system is expected to be second to none in this part of the state. AREG hopes by making VK5RSA part of this network that it will help bring amateurs together on VHF/UHF and will drive new activity on these bands!

We look forward to hearing you on VK5RSA and the link network! Come and give it a go….

Next Meeting: 19th February: Live ATV from 30km+ altitude! How to get involved?

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Project Horus began in 2010 as the brain child of a group of radio Amateurs here in Adelaide. Now, 11 years later, one of the ideas that has been discussed many times within the group is finally going to be attempted. A flight is tentatively planned for Sunday March 7th that will carry aloft our first ever digital ATV transmitter.

Live ATV from 30km+ altitude!

Adelaide from 100,000ft – Horus 12

How can you get involved?

So that as many people as possible can participate or at least attempt to receive the ATV pictures, the next meeting of AREG on Friday February 19th will feature a presentation and Q&A session with Mark VK5QI. He will take you though everything you need to know about how to receive and decode the ATV signal.

What system are we using?

For the first launch, we are going to use the following transmitter settings:

  • Transmit Frequency: 445 MHz
  • Modulation: DVB-S, QPSK, r=½ FEC
  • Symbol Rate: 1Msps
  • Video Resolution: 704×400

This will produce fairly low quality video, but will give the best chance for the payload to be received. Once we understand what the achievable signal-to-noise ratio (SNR) is for a typical flight, the symbol rate (and image quality) can be increased on future launches.

Receiving DVB-S Signals – Hardware

The most ideal way to receive signals from this payload is with a dedicated DVB-S receiver like the Minitiouner Express ( https://www.datv-express.com/ ), however it’s also very possible to receive it with Software Defined Radio receiver setups, such as the ubiquitous RTLSDR devices. You will also need a 70cm antenna with some gain, and a low-noise pre-amplifier.

While some DVB-S set-top boxes may tune down to 445 MHz, the very low bit-rates that we will be transmitting from the payload will likely be incompatible with them.

Suggested Software-Defined Radio Receivers

There’s a huge range of SDRs available which are fit-for-purpose in this application, provided you put a low-noise-figure preamp in front of them – ideally one with band-pass filtering. Examples include:

Mark testing the ATV receive across the bench

More detailed instructions and information will be posted to our website in coming days. Stay tuned!

Meeting Details

The main meeting will be held at the clubrooms, 1 Phelps Court, Fulham at the Fulham Community Centre. Doors will open from 7.15pm (ACDT) with proceedings starting at 7.45pm (ACDT) (0915z). For those unable to attend in person, we will have online options available too!

vk7hh-hrdx
YouTube_(2015-2017)

The meeting on February 19th will also be live streamed on YouTube thanks again to Hayden VK7HH and his HamRadioDX Channel.

For members unable to attend in meeting hall in person, there will be a members only Zoom channel available as well.

Links to these will be posted closer to the date!

January 15th Meeting: Electro-Mechanical Pin-Ball Machine Restoration

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The next meeting of the Amateur Radio Experimenters Group will be held on Friday January 15th. The club will meet in person at the Fulham Community Centre, Phelps Court, Fulham with the doors opening at 7.15pm. The presentation will get underway at 7.45pm ACDT (8.15pm AEDT, 7.15pm QST, 0915 UTC).

This month’s topic is a little different, but equally fascinating. We will enter the world of Electro-Mechanical Pin Ball machine restoration thanks to Scott VK2JAX. Scott was talking about his activities during one of the clubs members Zoom round table gatherings, and enough interest was expressed that we decided to bring it to a main meeting to share with everyone!

Scott’s journey started in October 2019 when he was looking through Facebook Marketplace and saw a Pinball machine that was a little worse for wear. He couldnt resist purchasing it, and so began the long task of restoration. In this talk, he will go through the activities so far involved in restoring “Jungle”, an Electro Mechanical (EM) Pinball from 1972.

Topics covered will include

  • Why a Pinball for restoration?
  • Tools required
  • Different parts within a machine
  • The Back Box clean up (Stepper units, Score Reels)
  • Coin Door
  • Bottom Panel (Relay Bank, Score Motor)

You will learn about challenges faced, and the relaxing journey of restoring an EM pinball machine!

In addition to the face to face meeting opportunity, the meeting will also be streamed via Zoom for AREG members around Australia.

Non members will also get a chance to see the show streamed live via Hayden VK7HH’s HamRadioDX Youtube channel! Links for the specific Youtube live stream will be shared a few days before the event.

Keep watching the AREG website for details!

AREG Remote HF Receive Site – Now Open to the Public

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AREG is pleased to announce that we can finally open ports on our HF Remote receive site to the general public.

The AREG HF receive site, located ~100km north of Adelaide, in South Australia, is now operating a publicly accessible KiwiSDR 4 channel receiver. This is the first active public service that the club is offering from the site. The system is currently using a broadband mono-pole vertical antenna.

AREG members also have access to much, much more, including dedicated members only KiwiSDR receiver channels, band by band high performance SDRs (Airspy HF+ Discovery, via SpyServer) on 160-20m, APRS-IS HF RX gateways and Weather Stations. If you are interested in joining the club to experiment with these other services, please (click here).

The site, which has been in development now for approximately a year, has other member services planned into 2021. Stay tuned as we continue to experiment and expand our capabilities at the site, including potential Reverse Beacon nodes, FT8 skimmers, WSPR skimmers and VHF monitoring services.

How to Access the Public KiwiSDR?
You can access the public service from the following web address:

kiwisdr.areg.org.au:8073/

Thanks Beam Internet!

AREG wouldn’t have been able to make this possible without the support of Sam from Beam Internet, who have sponsored our internet feed at the site.

Beam provide wireless internet connectivity to communities right across the Barossa Valley and northern Adelaide Plains.

Thanks team for your support of experimental Amateur Radio!

Using the KiwiSDR
For first time KiwiSDR users the following notes should be considered

  • Windows: Firefox, Chrome & Edge work; IE does not work.
  • Mac & Linux: Safari, Firefox, Chrome & Opera should work fine.
  • Open and close the panels by using the circled arrows at the top right corner.
  • You can click and/or drag almost anywhere on the page to change settings.
  • Enter a numeric frequency in the box marked “kHz” at right.
  • Or use the “select band” menu to jump to a pre-defined band.
  • Use the zoom icons to control the waterfall span.
  • Tune by clicking on the waterfall, spectrum or the cyan/red-colored station labels.
  • Ctrl-shift or alt-shift click in the waterfall to lookup frequency in online databases.
  • Control or option/alt click to page spectrum down and up in frequency.
  • Adjust the “WF min” slider for best waterfall colors.

AREG Handheld ARDF Picnic – 12:00pm Saturday January 9th

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VK5ZM hunting 2m “Foxes” in 2019

The next AREG hosted fox hunt is planned to be an ARDF “hand held – on foot” style event held in Drage Park / Riverside Park, in Felixtow, just 6km north east of the city centre (near the Kelmzig O-Bahn bus interchange). Members and visitors are welcome to join us in the park from 12.00pm, Saturday 9th January 2021.

AREG will deploy a minimum of 5 beacon transmitters on the 2m amateur band (144MHz). The challenge will be to see who can find all of them the fastest!

To participate, you will need to do a SA MyGov COVID Checkin with us at the start, and ideally bring along your 2m (144MHz) direction finding antennas and receivers. We will do timed staggered starts and you will be free to hunt the transmitters in any order you like!

For those who dont have any equipment, take a look at (this design) by NT1K! It is very simple and quick to put together! Add a variable attenuator and a receiver and you are away!

For those who aren’t sure, AREG is hoping to have at least 1 or 2 loan sets of gear available, based on the very popular VK3YNG sniffer receivers, or we can arrange to buddy you up with one of the club members who do have equipment so you can get a first taste of fox hunting ARDF style.

For those not into fox hunting, but who would like to gather and welcome in 2021 with all of us at AREG, we are also promoting this event as the AREG Summer BYO Picnic for 2021.

This will be a COVID Safe event with family groups spread out across the banks of the Torrens to observe social distancing requirements. AREG has picked this location as it has lots of amenities for all of the family. There are public BBQs, a kids playground and public toilets in the area as well as ample parking in the Drage Reserve car park. The marshaling check-in point will be marked with AREG Flags and will be located on the south side of the river Torrens near the Riverside Park western BBQ area (west of the play ground closest to the Drage Reserve Car Park).

We will also endeavor to have someone monitor the VK5RSB 70cm repeater on 439.900 (91.5Hz CTCSS access tone) to help guide anyone in who is having problems finding us.

We look forward to seeing you there!

Project Horus: Test flight towards VK3 – SUCCESS!

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UPDATE: Flight a success! 

Thanks to all that helped track the flight today! The tiny payload travelled over 550km from the launch site in Adelaide, to land near a piggery just outside Bendigo. Hopefully it gets recovered soon!
RS41 PowerSave Test Flight PAth
I recorded the following callsigns decoding telemetry:
AXB2035 (SWL), VK3AGD, VK3BQ, VK3EEK, VK3GP, VK3JED, VK3KZM, VK3NCC, VK3OF, VK3OHM, VK3TPM, VK3TWC, VK3WRE, VK3ZPF, VK5DJ, VK5EI, VK5HS, VK5IS, VK5KX, VK5LJG, VK5MAS, VK5MCA, VK5NTM, VK5PE, VK5QI, VK5RK, VK5ST, VK5TRM
… also a special mention to N0CALL, who received 154 packets.
RS41 PowerSave Test Flight
Thanks to all that setup the decoding software – one of the aims of this flight was to get more people setup to decode telemetry from these payloads, and get feedback from users to help improve it. There are a few groups in Melbourne that are planning on using the same kind of telemetry, so more listeners in VK3 able to decode will make their flights even safer.
73 and cheers,
Mark VK5QI

Tomorrow at ~9AM ACDT VK5QI is going to launch a lightweight (<40g) balloon with a 70cm 4FSK transmitter onboard. This is a test of some software updates to the 4FSK transmitter payload (a reprogrammed RS41) to improve the battery life. There will be ~30 second gaps between telemetry transmissions, with short ‘pips’ every 5 seconds so you know you are on the right frequency!

The transmit frequency is still subject to change but will most likely be 434.200 MHz. (Note that this is different to our usual Horus 4FSK frequency of 434.660 MHz – this is because there are a few 70cm repeaters in Melbourne with inputs near this range).

With a bit of luck this one should make it into VK3, and reach an altitude of ~23km or so. This should make it receivable from western Victoria, and likely from Melbourne too.

If you want to have a go receiving the telemetry from this flight, you’ll need a SSB-capable 70cm receiver (or a SDR), and my horus-GUI telemetry decoder software ( https://github.com/projecthorus/horus-gui ).

A brief guide on setting this up is available here: https://github.com/projecthorus/horusdemodlib/wiki/1.1-Horus-GUI-Reception-Guide-(Windows-Linux-OSX)

Note that this flight is going to head east *very* quickly, and may go out of range of Adelaide receivers during the flight. If you know anyone in VK3 who might be able to receive this please forward on this information!

Tracking of the flight is available via the following link: https://tracker.sondehub.org/?sondehub=1#!mt=osm&mz=8&qm=6_hours&mc=-35.40036,140.03814&f=HORUSBINARY&q=HORUSBINARY

Next AREG Meeting: A Virtual Christmas Party – Friday December 18th

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Merry Christmas everyone from the Amateur Radio Experimenters Group!

We have finally made it to the end of 2020 and what an unprecedented  year it has been! To draw a line under this year’s events, we are inviting our members to gather online this Friday night for a Christmas Chat on Zoom, hosted by our president, Matt VK5ZM. Bring your glass and share some cheer as we all start planning for 2021.

The Zoom session will open at 7.45pm ACDT (8.15pm AEDT, 7.15pm QST) and will last as long as the merriment prevails!

AREG will resume meeting in person in January and has some events in the wings for the fox hunters as well as a club picnic being planned.

Stay safe everyone and we wish you a merry Christmas and a Happy New Year for 2021!

Friday Foxhunts: Next Adelaide hunt 11th December 6.30pm

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On Friday 14th of November, three hunters set out to locate the two foxes that were hidden by Theo, VK5IR. The hunters were Mark, VK5QI, Louis, VK5FLY and Allan, VK5MAD. The first fox was hidden low in a tree at Victoria Park, south of the CBD and the second fox was stuck to the flying fox at a playground in St Clare, next to the St Clare Recreation Centre.

Both Mark and Louis were successful in locating the fox at St Clare and this was really a job well done as this fox only outputs 100mW so was very hard to hear. Mark was also successful in locating the other fox at Victoria Park which he found first before setting off for the low power fox. Unfortunately Allan had radio issues and called it a night early but has vowed to return for the next hunt.

The next hunt is planned for the evening of Friday the 11th of December and with hunters meeting at Lockleys Oval, Rutland Avenue Lockleys from 6.15pm and the hunt will commence at 6.30pm. Everyone is welcome to join in and we hope to see you there.