Mt Marulan VK2/ST-039 - my first failed activation


Having not been out on summits for a little while I received a push by my good friend https://www.instagram.com/trig_ventures/ who is a frequent hiking buddy and another good friend to try and activate VK2/ST-039 Mt Marulan.

Reading blogs from VK1MCW, VK1AD and VK2IO we followed the GPXs within the files section here on groups IO.

Arriving at the G98 trail head, we noted a new sign compared to other blog images noting the gate was now PRIVATE, which without direct permission we did not want to enter.  We checked the other 2 gates on the eastern side of the fence, both were also locked.

Noting some comments on some older activations from VK2IO and VK2HRX they mentioned the trail comes out near Tiyces Lane further to the south.

Heading to the very end of Tiyces Lane the former brown sign indicating the trailhead direction was missing compared to VK2IO's blog

Once arriving at the trail head a nearly 3km climb awaits you - I suggest not trying it on a 30 degree day like we did. 

Arriving at the trig was a feat that was celebrated by Trig_Vetures

Sadly HF conditions were a complete blow out - not a single call in response to my CQs on 40 or 20m.

I could hear faint murmers of VKFF parks activators on 7.144 but not actual words. VK1AD reported he could not hear me and I could not hear him on the usual workhorse band of 40m. Mt Marulan has become my first failed activation. With that steep climb I doubt I will be returning in a hurry either!

A refreshing ginger beer was had at the Hiberian Hotel in Goulburn and a safe return in the early evening was a welcome finish. VK1AD advised the MUF for that time as 4MHZ

Boboyan Range VK/AC-044 - Epic road trip!

It has been a long time between SOTA outings!

After almost no activating in a long while, I decided to put a little project radio I had been playing with, the Chinese clone USDR radio from AliExpress. After some work to get it aligned, I decided it needed an on-air outing.

Not having been to many Namadgi summits post the 2019/2020 fires that tore through much of the national park, I wanted to return to one of my favourites, Boboyan Range, AC-044. Located on top of a flat eucalypt plateau, accessed by working the contour lines filled with black wattle and other calf and ankle-poking foliage entirely off-track, navigating to the summit requires bush bashing and a keen eye on the GPX GPS track.

Finding the little rock cairn that has been added to by consecutive activators nestled amongst the juvenile gums, I wanted to mark the exact location for the future.

Setting up on my blue tarp, running a linked 20/40m end fed antenna with a QPRGuys 40-10 EFHW tuner with the long wire thrown over a hanging branch, set up could not be lighter or more simple.

Andrew VK1DA was located on a nearby summit, Mt Livingston VK2/ST-093 I was able to test the USDR’s inbuilt CW decoder - video below

The ‘other’ Andrew, VK1AD was also able to offer a summit to summit contact, located on Mt Stromlo, VK1/AC-043 and he recorded the following exchange to capture the audio quality that he received

With the K Index in the toilet, I was still happy to work more than enough stations to qualify the summit, with reports as far as the South Island of New Zealand

Following the activation and spending almost an hour on the summit, my walking compainion and I packed up and headed back to the car, thankful for the downhill run. Finding the car in the small culvet that we had left it, we headed off to the Mt Clear campground for refreshments. Continuing a short distance south on Boboyan road to the historic Brayshaws Hut.

The original plan was to continue south, stopping again at Adaminaby before doubling back to Coooma and home via the Monaro Highway. Immediately after leaving Boboyan Road where it meets the Snowy Mountain Highway, we encountered a road closure due to a tragic truck accident that had occurred approx 90 mins prior in which the truck crashed and caught fire. This meant the road home would be closed for the foreseeable future. Deciding to turn west we headed towards Tumut. Not before visiting the big trout at Adaminaby.

Dropping down the mountain pass and entering the hydo hamlet of Talbingo we encoutered 2 Emu on the side of the road, grasing in the falling dusk.

A lovely day trip out to test out the USDR turned into an 11-hour, 500km excursion taking in many unplanned sights, as captured by my APRS track from my Kenwood 710 mounted in my car.

Multi Mode 70cm DIY Repeater Build Project Pt2

Well I finally had some time with COVID-19 raising its head again here in Australia to get back to the 70cm Repeater build as mentioned in Pt 1

Lets layout the hardware, before I get to my call for help.

The radios:

2 x Tait TM8235 just like the one I have hosting my UHF Winlink gateway

Taits.JPG

The modem:

1x Repeater Builders MMDVM v4 & Raspberry pi hat sitting on 1 x Raspberry Pi B3+

The duplexer:

flat pack UHF cavity from the 409 shop

Now to my problem

I can’t make it work!

Below I have collated the info from the Tait manuals as well as what I currently have as my setup.

Radio DB15 Pins

15 Ground

13 Audio Out

12 PTT

8 +13.8V Body switched

7 Audio input

6 RSSI indicator

MMDVM DB9 Pins

2 TX Audio

3 DVM Inhibit (active low)

4 RSSI

5 PTT

6 RX Audio

8 Ground

9 +13.8V

The actual problem: I have hooked it all up and on the pi-star home page - it NEVER receives any valid DMR signal. I have used the audio pot to turn down to make sure there is no clipping.

Tait Pin out.png
GPIO.PNG

Winlink in VK

Check and send email from almost anywhere. Winlink - email over Radio

Many of us in Amateur Radio can remember the moment our interest in the hobby sparked, I certainly can. Growing up, I learned to sail at the local sailing club in Twofold Bay, Eden NSW. Hearing long-distance cruisers talk about making HF contacts while under sail as well as sending emails over the radio. Considering the worldwide web (as it was known then) was still in its 56K dialup stages this blew my mind. And the rest, as they say, is history.

Email over radio?

Email over the radio isn't terribly new, but it was and still is new and exciting for me. The main system is simply called Winlink. This is essentially a collection of protocols or languages that facilitate the RF to IP link to an Amazon Web Services (AWS) distributed email management system. Additionally, Winklink has a windows only application they have released for operators to use called Winlink Express, formally known as Winlink 2000. This brings together modes such as ARDOP, AX25 Packet, PACTOR, VARA FM or even just using an internet connection via TELNET, into one unified inbox and email client. Personally I use the Linux / Raspberry Pi application called PAT, which is lighter weight and thus less featured client, but it runs well on the Raspberry Pi and I regularly use ARDOP for HF email connections into VK3MIT and VK3DPW. It should be noted that HF email connection is SLOW - approx 1 page of text can take 5 mins to send - this is approx 300bps (this is changing with VARA bringing comparative lightning speeds – but it is trapped in the Windows ecosystem), alternatively the 'faster' modes such as ax25 packet can support 1200bps or 9600bps connections. Still slow by internet speeds but these systems were never designed to compete or replace the internet. However, they work in many many more places.

Gateways?

A gateway (AKA an RMS -  Radio Message Server) is simply a 2 way RF > IP bridge that facilitates the connection to the Winlink AWS servers. Some are Hybrid connections - Winlink describes these hybrid connections as a network that "takes advantage of the speed and other benefits of the Internet when and where it’s available, but also provides end-to-end email transport and delivery if the Internet is down--or even if it completely disappears everywhere. It does this transparently, and routes messages automatically from sender to recipient without much adaptation by users, except that they must use a client program that supports the new design (currently only Winlink Express). Older programs like Airmail still are compatible with the system and hybrid gateways without compromise to past performance or capability, but can't take advantage of the new network's features. Users can switch to RMS Express to gain the advantages of the Hybrid Network design" #

What’s the situation like here in Australia (VK)

In the US there are VHF & UHF gateways (shorter range- think line of sight) but they are almost all contained in the US - not technically true since I run one here in Australia but nowhere else worldwide has the density of the US. It is more common to have gateways on the HF bands. My post on my VHF – Now moved to to UHF- email gateway can be found here. http://wadeabout.com/blog/a-vhf-winlink-g

Comments from VK users:

VK3FUR

Rig: Modified Codan 9323, Icom 7100

Antenna: Diamon 40m and 30m whips, or linked inverted vee

Software: PAT, Ardop on RaspberryPi

Used for:

 - Letting friends and family know that we have arrived at camp but don't have phone signal

 - Coordinating skeds

 - Sending updates about our camping trip

VK3FUR_1.jpg
VK3FUR_2.jpg


VK4LM Winlink Remote Mail Server

The system is scanning dial frequencies 3590 7057 10130 14100 using modes; Ardop, Pactor, and VARA HF with a IC7200 connected to a Chameleon CHA SKYLOOP antenna and an FT8800 on 144.075FM for VARA FM on a home brew 3E horizontally polarized yagi. The PC stick has been getting a work out with concurrent connections on Pactor  HF and VARA FM VHF without a problem.

We have been getting connections from ZL1 ZL2 ZL4 VA VK1 VK2 VK3 VK4 VK5 VK8 JA K7 SA6 as well as our local test team VK4JRC and VK4FLR on most bands and modes with good reports. Jack has been giving 160M a work out mobile also with great results (160M currently offline). Been able to maintain connections mobile on Mt Morgan range as well as Mt Morgan CBD. Capricorn Highway Burnett Highway and Gracemere CBD also work fine. Rockhampton CBD noise floor is a bit much. I have also used the gateway from the mobile on 30M in the CBD during the Emergency Services Day 2019. Watch this space for more mobile and field deployment testing.

Pictures, videos and more information can be found at http://www.cqara.org.au/index.php/winlink

New toy Lanchonlh HG-UV98 ARPS V/UHF HT

A chinese HT with APRS?

While scrolling around the internet recently I came across a Chinese branded UHF and VHF HT with built in APRS. The Lanchonlh HG-UV98 ARPS V/UHF.

I managed to snap one up for about AUD$200 delivered to my home. Its not as full featured as my Kenwood D72 HT but it is 1/2 the price, additionally it has BlueTooth access to the internal TNC (like the Kenwood D74) but it also charges by a micro USB!

2E925A69-90ED-43ED-99FA-B66B620FA0CA.jpeg

Like most HTs it included the near dummy load whip which went straight in the bin, and within seconds a SMA to BNC was added - I run BNC on every portable radio I own from the FT-857 to my DMR and FM HTs and my little APRS 1w tracker - when you have tired and cold hands BNC is a positive connection with gloves on rather than fiddling with the limited life SMA. I use the converters that seat within the HT recess on most of the HTs.

96E5C052-B7FB-4045-A5C3-EB29615D7CBC.jpeg

The manual that comes with the package is all in Chinese so that went into the bin too.
Here is the ‘english’ manual - and I mean that is the loosest sense. https://www.manualslib.com/download/1661386/Lanchonlh-Hg-Uv98.html

And there is a firmware upgrade available - so I added that straight away - the most noticeable change is on the GPS screen it shows the real Grid Square of the location
Firmware upgrade: https://hvdnnotebook.blogspot.com/2020/09/firmware-update-lanch-hg-uv98-aprs-radio.html

Now I mentioned BT - I was able to connect to my little android phone I have kept for portable radio operation using APRSdroid - worked PERFECTLY! using the same method I use with my Mobilinkd BT TNC. Essentially the same as setting up this HT: https://youtu.be/Mi-Hk2EwQVo

Well, I have had the HT for an hour - no doubt more to come!

Multi Mode 70cm DIY Repeater Build Project

Part 1

Because a ham never has one of anything, I have found myself with 2 spare Tait 8115 UHF 25w ex taxi radios.

I did have 3, but one has been repurposed to move my VHF Winlink gateway to UHF to allow me to share an antenna with my VHF packet set up.

So with 2 UHF Taits hanging around, I thought I might try my hand at turning them into a UHF multi mode repeater.

I grabbed myself a v4 of the Repeater Builder’s STM32 multimode DV hat for a raspberry pi and a flat pack UHF cavity from the 409 shop - they even tune it for you!

Taits.JPG

Double Summit Saturday VK2/ST-001 & VK2/ST-034

2755E684-2CFC-4645-B259-2C223A453D05.jpeg

I have been slowing down on my SOTA activities lately and I needed to get back out and activate some summits.

Thankfully Andrew VK1DA was keen to head out and knock over two summits being ST-001 - The shared location for the Captain’s Flat Weather Radar site and ST034, Mt Gillamatong near the NSW town of Braidwood.

The day was glorious - about 28-33 Degrees on an Aussie summer’s day and it seemed that every flying insect wanted to visit us.

0CD75D9A-165D-414F-AEBA-C37B309D17A8.jpeg

After great hour or so on 80m-23cm we packed up and started heading for ST-034 which was a hot walk up the fire trail to knock out some contacts on HF and 2m.

A7054E70-7BED-43EE-B677-0C1BB3752039.jpeg

Retevis RT73 Dual Band 20W DMR Mobile

Just before Christmas, I decided to splash out and purchase myself a new radio as a Christmas present. I really like DMR, and in particular, the way the Australian DMR+ network is structured.

The Network

Before getting onto the radio, let's talk about the Australian DMR+ network.

At the time of writing, there are 49 repeaters (including 2 WICEN only repeaters) on the VK DMR Network.

Map from https://vkdmr.vk2fly.com/repeaters.php

The VK network is structured in layers:

  • International TGs - User Activated (UA)

  • National TGs - 505 (VK Wide) triggers all repeaters on Time Slot (TS)2 and 5 (Nets) triggers all repeaters on Time Slot (TS) 1

  • State Based TGs 3801-3808 TS 1 triggers all the repeaters in that state but accessible outside the state as UA. A chat TG of 3809 and 3810 for WICEN is also available

  • Regional TG8 TS 1 is grouped into regional groups to allow regional communication

  • Local TG9 TS1 triggers only the repeater you are connected to.

  • Other DMR+ TGs are available as UA

For those that are not familiar with DMR as a digital mode - it uses Timeslots to share the same frequency. 

I regularly have TG 505 (all VK wide) on TS2 and TG 3801 (ACT) on TS1 as my two slots I am monitoring while I drive.

The Radio

8E8A46F8-A4EC-4299-9290-E46E974878AD.jpeg

Originally this radio was released as the Kydera ​CDR-300UV. Through some magical process Retevis has taken them over and rebadged them as the RT73 and releasing their own CPS and own firmware almost weekly to correct the utter dogs breakfast that Kydera has released.

Overall impressions - this radio is tiny. This is my secondary mobile in the car with a the Kenwood TM-710 ARPS rig as the primary rig with the RT73 mounted using double sided tape on the horizontal position on the passenger side of the centre transmission cover with no issues.

I really wanted to use the roaming feature of this radio (load up a series of DMR repeaters and it finds the one with the best 'connection' [highest RSSI for the nerds] with the ability to auto search when the connection drops too low), however, the CPS does now allow importing of channels yet so I manually only entered a Simplex zone and a zone for my local repeater.

Negatives - the radio is fine - the downside is the CPS - it is basically being written on the run, a new version is released almost every 10-20 days. I surmise this will settle down when the bugs are ironed out.

Interesting quirks include the ability to choose 3 different audio options - speaker mic, radio front-facing speaker, or side audio plugs (Kenwood style?)

New to me ICOM IC706Mk2 to HF + 2M radio pt3

IC706Mk2 Digital mode use

Tonight I swapped out my trust FT857 from it's role as my primary digital mode rig hooked up with my QTH Raspberry Pi for the IC706Mk2.

5E04D849-D513-4426-8AD8-2006DAE58B21.jpeg




I wanted to document the settings so that others done have to undergo the trials that I did.

Data should be in USB mode NOT RTTY.


After a little bit of fiddling and reading the [HAMLIB doc](http://hamlib.sourceforge.net/pdf/rigctl.1.pdf)

Screen Shot 2020-11-26 at 21.29.07.png


So now it is fully functional on PAT Winlink (ARDOP), JS8Call, WSJTX etc.

Screen Shot 2020-11-26 at 21.27.17.png


New to me ICOM IC706Mk2 to HF + 2M radio pt2

New to me ICOM IC706Mk2 to HF + 2M radio pt2

IC706pins.png

I have been in contact with Steve from XGGcomms, who understood my issue perfectly. The 706MK2 uses different pins to PTT HF and VHF. Pins 3 and 7 consecutively. He provided the below chart and advised me to ‘get out my soldering iron’ and insert a jumper connecting the two pins inside the plug covering and thus PTT will trigger regardless of band now - and that’s just what I did

I placed a short jumper about 10mm long connecting the pins

67082141-CFCC-47A2-8F4B-E1FDA095BB2D.jpeg

Time for a test!

While still getting to know the radio, I broke out mu portable pi and set about getting direwolf talking to the radio on 2M FM with PTT via RTS signals. Worked.

6DF09382-F758-421A-B11F-D25F725F6C56.jpeg

Lessons learned for others:

  1. Digital modes (normally conducted on USB) should be set to RTTY mode on the 706MK2, while FM modes such as APRS/Packet should use FM. Again using RTS for PTT signal.

  2. The radio is a thirsty beast drawing around 2A - make sure your power source will last long enough for testing, my small 1S 4 Cell LIFEPO4 battery was nearly dead by the end of the testing.

My QRO portable digital setup

83C292FC-A5AD-4EA5-83FF-C6075CACBA10.jpeg

The picture above shows my full set up now: IC706Mk2, GPS for location and timing, CAT, AUDIO, PTT interface from XGGCOMMS, and a small usb sound card to feed to brain of the whole thing - a raspberry pi 3B+ - A far cry from its first iteration: http://wadeabout.com/blog/portable-pi-update-new-capabilities

New to me ICOM IC706Mk2 to HF + 2M radio

New to me ICOM IC706Mk2 HF-2M radio

I have been playing with my new to me IC706Mk2 with a primary view to use as my high power portable station, including digital modes using the raspberry pi set up.

So far I have got the sweet light weight XGGCOMS ICOM interface with CAT (which is my preferred supplier for portable set ups) talking with the radio with PTT on HF, but I can't seem to get the radio to PTT on the 2M side of things.

Also I have managed to snap the tongue off the RJ45 connection on the mic, so I have ordered another from QSL Comms in Queensland.

Plans for the 706MK2

A fully capably high power portable rig (HF 100w, 2M 20W), that I can take on car camping and shorter summit hike activating that will give me full HF and 2M access for SSB and Digital operation. My normal Pi set ups give me WINLINK (email over RF), APRS (40m HF and 2M FM), JS8 for keyboard QSOs

References:

http://wadeabout.com/blog/js8-and-its-use-in-the-field-a-presentation-i-gave-to-my-local-radio-club

http://wadeabout.com/blog/satellite-aprs-for-the-backpacker-pt2

http://wadeabout.com/blog/a-vhf-winlink-g

icom-ic706mk2.jpg

Devil's Peak VK2/ST-003 lives up to it's name

Andrew VK1AD and I decided to do a double summit activation of Devils Peak VK2/ST-003 and Dingi Dingi Ridge VK2/ST-004 both on the west side of Mt Coree.

IMG_0530.jpeg

Devils peak lived up to its name. The climb wasn’t so much the struggle, it was more the bush bashing, leaf litter, and debris on the forest floor that slowed things down. But with a few breaks during the climb, we were rewarded with clear blue skies and a tiny breath of wind on the thickly vegetated summit.

Andrew and I operated on 2m SSB, 2M FM, and 1296.SSB. Activating on each band and mode. It was fantastic to see so many summit to summits from local activators - just like the old days!

Andrew’s oblong loop continues to produce good results, I was using the collapsable/telescopic dipole in both the H and V pol config.

Just as we were packing up on the summit we realised we were not alone… despite the remoteness of the summit, the harshness of the climb, and the thickness of the scrub, 2 bushwalkers stumbled on to the summit. I think they were just as shocked as we were.

55DC8DA6-5B9A-4291-A952-A6E42C0D5966.jpeg

On the descent, I regularly had to tell Andrew to slow down as he has a habit of blending in the scrub with his camo hat and bag. About 1/2 of the way down, Andrew was approx 5 paces ahead of me when I saw something fall from the tree between us, calling Andrew back we were greeted by a juvenile sugar glider or is a juvenile Dropbear that had fallen from the tree, maybe he or she had a bad nightmare. After a number of attempts to get it to climb the tree back to safety and the poor thing falling out again, we placed it in a nearby hollow to sleep off the day. NB: Dropbears are a nocturnal creature in the Australian Bush that have a thirst for tourist blood. They are often seen working in teams with Hoop Snakes.

Getting back to the car we scoffed some tucker before moving on to Dingi Dingi. We were not exactly filled with excitement about the second climb. The second summit was even more overgrown than the last time we summited it. It was evident that fatigue had started to set in as simple tasks like erecting our antennas were taking more brainpower than normal. At one stage I was unable to remember my callsign!

Packing up and falling down the mountain in somewhat of a controlled fashion we were out of there! Back safe and sound to Canberra in the late afternoon.

Satellite APRS for the backpacker pt2

Testing the prototype

So it has been a little while since I published pt 1 - Satellite APRS for the backpacker? the Idea, and I wanted to give you a bit of an update.

253B0D75-FBA4-4BA7-B720-9FF1A7D342C7.jpg

I have been testing a prototype antenna built by my good friend Andrew VK1AD with some good success now that the ISS has returned to APRS operations following a period of crossbanding.


Last night I was able to get into VK5ATN, roughly 1,100km away - not bad for my 5w handheld and the above antenna.

3283F5D4-7B5D-4480-9B89-34ABAF28791A.jpeg

A new backpack - and a look at all of my SOTA gear (summer 2020)

D1060DCC-BCAE-43EE-944D-BDCC5B5A1215.jpeg

So if you have been watching my most recent videos you would know that I am a little more chunky or ‘covid kgs’ have been found. My trusty 30L Berghous free flow backpack that I have been using ever since getting into SOTA has started to dig into my shoulders, as an ultralight pack (1.46kgs for 30L) it saves weight in not having extra padding for the shoulder straps and hip belt.

My good friend Andrew VK1AD had recently updated his pack and was giving it good comments.

He went with the 50L Caribee Ops day pack (below) - I couldn’t help but follow him down that path. I managed to snap up a “sand” coloured one from amazon.



While I was weighing and measuring packs etc, I thought it would also be a good idea to show you what I am carrying in this new pack.

My SOTA kit for summer 2020.

B4B1AE41-4133-4004-B8D2-11DE4410B6E5_1_201_a.jpeg

So from the top row left to right:

  • Elecraft T1 Tuner w/ a short RG174 jumper

  • HF Antenna ZS6BKW - resonate on 80/40/20

  • Yaesu FT817, mic, SOTABEAMS inline compressor, Anderson jumper cable in a waterproof Plano 1460 waterproof case

  • Black pouch for mast mounting (more below)

  • Samsung Tablet for logging using VKPORTALOG and APRSDROID

  • Kenwood TH72A APRS enabled dual-band HT with BNC adapter (all my radios are now BNC - HATE SMA) BNC w/ dual-band whip

  • Small green lunch box with SG labs 1296 transverter, power cable, supplied PCB 2 el yagi antenna

  • Personal first aid kit, with snake bite bandages and other such items needed to look after yourself

  • Zippy 4200 Lifepo4 battery with Andersons fitted

  • Small stuff sack with outdoor toiletries (TP, mini trowel, hand sanitiser)

  • Buff/neck gaiter given to me by a diving client to cover my neck and ears in the sun

  • Pink trail marking tape to mark any off-trail expeditions

  • Mini survival / outdoor signaling kit

  • 8m Fiberglass pole - actually it comes as a 9m but you remove the top sections for strength.

F97CEFC2-5453-4798-A350-F2EEEF1F79D3_1_201_a.jpeg

My mounting kit for the pole - with these items I can put the mast up anywhere:

  • 3D printed 3 points guying triangle

  • 2 friction grip straps to strap to any vertical trig or pole

  • Lightweight tent pegs to secure the triable mount, and the ends of the dipole

All told, the new pack (1.77Kgs) even with the new capacity dry loaded - no food or water brings me in at 8.24kgs

Satellite APRS for the backpacker?

Satellite APRS for the backpacker?

Part 1 - The Idea

So I had this crazy idea. I am sure it is not unique but it is unique to me.

After all the COVID-19 lockdowns have eased and I am back out hiking and camping again, far from civilisation, long after my mobile phone is useful for anything other than a camera and audio book reader. I arrive at a lunch spot, or set up camp for the evening. I take out my trusty Kenwood D72 Handheld radio with built in TNC, connect it to a lightweight folding antenna, point it skyward and burst off some APRS packets to mark my position and status messages via passing satellites. Sounds crazy right? Well it's actually doable as a radio amateur.

Down here in Australia we don’t have access to the geo-stationary (GEO) satellite QO-100 that covers the entire Eurasian landmass from the east coast of Asia to the west coast of the UK that was launched recently and has been welcomed by many Amature Radio Operators under it’s ‘footprint’.

What we do have access to is a number of Low Earth Orbit (LEO) satellites equipped with flying APRS digipeaters. These LEOs pass over a number of times a day and passing over with various ‘elevations’. The most famous of these is the International Space Station (ISS). For clarity, I have lumped the ISS into the collective term for satellites.

ISS

ISS

The ISS is equipped with an Automatic Packet Reporting System (APRS) digital repeater (digipeater) that takes packets it hears coming from earth and re-transmits (digitally repeating - digipeating) back down from space on the same frequency much the same as an earth bound digipeater. The difference here is the footprint! During experiments from my house in Canberra ACT, I am regularly heard in Adelaide, South Australia.

The hearing part is important. These ground stations are run by other amateur radio operators, and take these heard signals and put them on the internet, called internet gating (igating) while their stations are called satellite gateways (SATGATES) allowing your location and short status message to be seen by anyone with an internet connection. The ISS is one of 8 satellites that all use similar settings and frequencies. There are however, others like FALCONSAT-3 that operate on different settings and frequencies. I have chosen to only use those that have the same settings as this allows set and forget access to a network of satellites.

Based on my research (May 2020) the below are correct. It is not as simple as it sounds to find all the info as there isn’t a clear and concise directory - I hope this table helps you.

Edit: June 2020 PSAT2 is no longer working on APRS

AREDN in VK1 V1.1

AREDN in VK1 V1.1

I have been tinkering with the MESH IP networking system called Amateur Radio Emergency Data Network (AREDN) for a while now.

It’s essentially a private (on AR freq) ip networking mesh! As long as one mesh node can see another, it is part of the mesh.


The AR relevant frequencies are just beside the open wifi frequencies on 2.4 and 5.8Ghz so AREDN has written a custom firmware to turn professional and prosumer level networking equipment into a mesh capable radio.

Currently, I have a NanoStation M5 on 5.8Ghz, connected to a GL.iNET AR750 dual-band travel router on 2.4Ghz AREDN, interconnected using a Netgear managed 5 port switch. On the network, I am ‘serving’ or acting as the server for Team Talk 5 IP chat, video stream and PTT IP radio. All 12v powered - the switch is the only thing I need to figure out a POE feed step up from 12v to 48v.


Using VLANs on the switch I have also added internet connectivity to the mini-network. 

Now just need get more nodes online. There is the possibility to add ‘tunnels’, essentially VPN connections to create ‘logical’ connections to other nodes or full mesh networks where no RF path exist.


Read more about AREDN https://www.arednmesh.org/sites/default/files/sites/default/files/pictures/user12/AREDNmesh%20Brochure%20Final%202018.pdf

Below is a set up from Mark KE8LEN that I aspire to

Mark KE8LEN.PNG



 

My Mini SDR Farm v1.1

public.jpg
Welcome file

My Mini SDR Farm v1.1

I recently posted a picture on my twitter account showing my little Raspberry Pi SDR ‘Farm’ and it was one of the most liked pictures I have ever posted(!). I wanted to expand on the info from twitter as there seemed to be a high rate of interest.

Antenna & Coax

My antenna is a diamond D130J Discone, with a ~25m coax run of LMR400 from the roof of my second storey on my suburban townhouse. https://www.diamondantenna.net/d130j.html

LNA

I use a 12v Low Noise Amplifier (LNA) from the roof coax before it gets to the SDRs, I have chosen to do this in the shack in the event I want to repurpose the discone as I only have one other dual band antenna on the roof. This is my LNA https://www.ebay.com.au/itm/LNA-RF-Broadband-Amplifier-Module-Signal-Booster-1-3000MHz-2-4G-20dB-HF-VHF-UHF/303138247368?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

Power Divider

To split out the feed from the antenna and LNA, I found this wide band power splitter on eBay. https://www.ebay.com.au/itm/MECA-RF-Power-Divider-0-8-2GHz-SMA/181676778993?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

SDRs

I have been dudded before by fake USB RTLSDRs, so now I only buy from a known source, and this guy is THE business!

https://www.ebay.com.au/itm/RTL-SDR-Blog-V3-RTL2832U-1PPM-TCXO-HF-BiasT-SMA-Software-Defined-Radio/272411458376?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

Filter

The only filter in the while system is a 1090Mhz filter on the ADS-B receiver to filter out any other ‘trash’ signals. I have seen a large improvement using this one. http://www.ebay.com.au/itm/1090MHz-ADS-B-Aeronautical-Bandwidth-14MHz-Band-pass-Filter-IL-4dB-SG-/113757709997?hash=item1a7c7ce6ad

Raspberry Pis

The processing power for each of the streams or data sources is the Raspberry Pi 3B+, yes the 4 is out but I still really love the 3b+ for all my work. Again a reputable source is important. In Australia I usually use Core Electronic, however Amazon Australia has been just as fast and cheap when Core is out of stock.

Things they are used for at my place

ADS-B

This is one of my favourite projects at my house at the moment. Frustrated by the censorship shown by Flight Radar 24, filtering out flights at the request of rich business owners while the aircraft is still pinging away transmitting data is crap. If they, and others such as military aircraft, are transmitting, I want the data. So I set up my own downlink station. This is the preferred model for me: https://flightaware.com/adsb/piaware/install

Streaming Aviation Audio

I am currently testing the streaming of AM VHF audio of Canberra Airport Departures using Broadcastify. https://wiki.radioreference.com/index.php/Raspberry_Pi_RTL-SDR_Broadcastify is the instructions I used. And here is the link to the stream https://www.broadcastify.com/listen/feed/31146. It is still very much in the test phase.

VHF WSPR reception

Previously I was using my FT817 and an audio interface to monitor 2m VHF WSPR transmissions from around the region. I co no longer dedicate that radio to the job so looked to the raspberry pi and RTLSDR to pick up the slack. This is the model I used https://github.com/Guenael/rtlsdr-wsprd