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Ham Radio Mesh Networks – fun and fulfilling

16 May 2016 | by Michael KG9DW | Leave a Comment (0)

Two of the most rewarding aspects of ham radio for me are technical challenges and operational missions. My electrical engineering background has limited use in my day job as a technical leader for a Fortune 50 insurance and financial services company. Tactical missions (events, problems) are also not a part of my regular work as I focus on 6, 12, and 18 month strategies. I’m most content and excited when I can take my love of engineering and apply it to real missions in real life!

K9ECB – Erin – Using AREDN mesh to retrieve weather and soil data.

For me, that’s what the Amateur Radio Emergency Data Network (AREDN) is all about. I’ve shared here before about using AREDN’s mesh software to provide access to our D-STAR repeaters. My daughter has also started usingAREDN to gather weather data from a home-brew Arduino weather station located in a corn field away from power and internet. Our local emergency management organization is considering a build-out of the mesh with remote pan-tilt-zoom cameras to be used for weather spotting. This use case provides us the ability to watch approaching storms from the EOC to confirm and augment our spotter teams. And hams in Southern California are working with emergency management teams to provide live video and audio of events.

The concept is to take commercial off-the-shelf (COTS) technology and re-purpose it into a mesh data network. Unlike my early days of playing with 1200 baud packet on the AMPRNet 44.x network, AREDN is using 2.4, 3, and 5GHz ham allocations with TP-Link and Ubiquiti gear to provide a mesh network with speeds over 100 Mbps.

An omni and point to point AREDN 5GHz mesh site feeding a D-STAR repeater.

For some parts of our hobby, the barrier to entry is price. That’s not the case for AREDN. For under $100 you can have a working node. With some careful purchases from eBay and some bargains from online retailers you can have a fully functioning mesh of 3 nodes for under $200.

When I play with HF, I never know who I’m going to find, what mode I’ll end up using, or if I’ll have a ragchew or a short contact. Mesh networking isn’t like that. It isn’t even like VHF/UHF repeaters. “Meshing” is about setting up some base infrastructure in an area and then using it for specific purposes (like my D-STAR repeater or weather spotting example) or preparing for on-demand deployments (like the Southern California local emergency management use case). There are groups in Tennessee doing large exercises passing incident command system (ICS) messages via Winlink that is self-sustaining on an AREDN mesh. There are those using Raspberry pi voice over IP gateway and IP phones to provide communication between tactical and command teams. And there’s even a group with an HF radio controlled across the mesh providing long distance off-internet communications using an existing station rather than doing a field-day like setup at a command post.

The core AREDN development team is made up of six volunteers. Because the software is open sourced, other assist, modify and customize to meet their needs. Depending on your level of interest, you can code and hack away or you can install the software and just stay in the graphical interface. It’s more than working with computers, as understanding microwave antennas and limitations are important for a successful implementation. Sure, you can plug-and-play two nodes in a hamfest parking lot and have a mesh. The real challenge comes when you want to build a data backbone between multiple sites and provide reliable service to your mission!

There are over 600 hams that have connected and registered on the AREDN.org website to interact with other hams wanting to do similar things. Thousands more have downloaded the software. The AREDN just released version 3.16.1.0 of the firmware bringing with it support for new devices, faster throughput, real-time stats, and other operational management features. More impressive is that the team released a substantial upgrade in December. This team, with help from beta testers and early adopters is on pace to have two major releases each year.

The amateur radio community is quite diverse, both in people and technologies. I’ve thoroughly enjoyed experimenting with AREDN and with using it for a mission. If your local ham community is interested in a new challenge, especially if you’re looking for a way to get the next generation of hams involved, consider getting involved with mesh networking and AREDN.

Michael Brown, KG9DW, is a regular contributor to AmateurRadio.com and writes from Illinois, USA. Contact him at [email protected].

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VE7CNF’s Lightwave Cloubounce / Scatter Tests

16 May 2016 | by Steve VE7SL | Leave a Comment (1)

After our recent lightwave CW QSO, described here, Toby (VE7CNF) has been re-focusing on refining his lightwave system for weak signal non-line-of-sight (NLOS) cloudbounce and scatter mode experiments.

His testing to date has been limited to within his own suburban yard, with the transmitter being set up on the south side of the house and the receiver set up on the north, while basically pointing things straight up.

Several tests have already been done with exciting results, including audible CW being returned from a low (5,000') cloud ceiling and weaker returns noted on clear air scatter but readily detected in the CW QRSS mode. Toby has also interfaced his PC audio, via amplifier and FET driver, to enable him to use WSPR and JT9 modes, resulting in positive signal returns using these two digital modes of modulation.

Toby described some of his results and methodology in a recent e-mail updater:

I've done some lightwave backscatter experiments this last week. The transmitter is on my front deck, pointed straight up as verified using a level across the lens end of the box. The receiver is in the back yard and pointed up also. Between the two, the house is about 30ft high and blocks any direct light.

Last night May 8 UTC was clear and I was getting a QRSS10 level signal with the receiver pointed at elevations from 70 to 85 degrees, through the transmitter beam. There was nothing received from straight up, so the clouds were too high for cloud backscatter. At 80 degrees elevation I got the best signal. I've attached an Argo screen grab of QRSS10 (FSK CW with the 570 Hz tone as key-down).

QRSS10 CW clear air scatter return signal

During my tests I used the QRSS3 speed setting of Argo to point the receiver around and find the signal. It was pretty weak but still visible at that speed. When I slowed to QRSS10 it became easy copy.

WSPR2 was decoding consistently and JT9 was about 70%. I tried JT65, BPSK31, and MFSK8 but the SNR was too low for those to work.

JT9 cloudbounce return signal 14,000 - 24,000 FT

Here's Vancouver Airport cloud data for last night:

May 8, 2016 UTC CYVR clouds and temperature/dewpoint data:
0500 FEW CLOUDS (1/8 - 2/8) 14000 FT, SCATTERED CLOUDS (3/8 - 4/8) 24000 FT, 14 C / 11 C
0600 FEW CLOUDS (1/8 - 2/8) 14000 FT, SCATTERED CLOUDS (3/8 - 4/8) 24000 FT, 14 C / 9 C
0700 FEW CLOUDS (1/8 - 2/8) 12000 FT, FEW CLOUDS (1/8 - 2/8) 22000 FT, 13 C / 7 C

... I'll try CW and digital again when there's some lower cloud conditions. That’s tough to get without rain at the same time.

I did get dew on the receiver last night, so I'll be adding heating resistors inside the boxes to keep the lenses warm. Electric heating has worked great to keep dew off the optical surfaces of my telescope. I'll also look at adding shrouds to shield the lenses from the cold sky.

More from May 15th:

Last night was good for backscatter from low clouds, at 1300 to 1900 ft according to airport weather. I had to stay up late though, as the cloud didn't move in until midnight.

I've attached a couple of CW recordings. Early on the signal was weaker with QSB. Later it was strong and solid.

I've also attached a screen grab of WSPR2. Signals were up around 0dB this time.

WSPR cloudbounce return signals 1300 - 1900 FT

I played with a bunch of digital modes and FMHELL and SSTV. Everything was working pretty well off the clouds.

SSTV cloudbounce return signal

The nextstep is to move the rx farther from home, then to try sending signals over to John or Steve by cloud bounce.

You can find more information and all equipment details, including schematics, on VE7CNF's lightwave web pages here.

Toby's nearest lightwave neighbour, VA7MM, is in mid-build and is working to complete a system capable of running overnight cloudbounce / scatter tests between their two respective backyards ... the NLOS distance is about 15 km. Although the path includes some bright commercial lighting QRM, with narrow-band modes such as QRSS or WSPR, it may not be a problem. I suspect one of the biggest problems will be getting suitable weather as, here on the west coast, dense clouds usually turn into rain very quickly, especially near the coastal mountains where Toby and Mark are located.

I find Toby's results to be both encouraging and exciting! It will be interesting to try some cloudbounce between their respective stations and my own and maybe hopping the NLOS path across cloudy Georgia Strait. It may well be possible to do this in one of the quicker QRSS CW modes such as QRSS3 or QRSS10, both of which can have fairly fast exchanges of the required information (calls, signal report and final confirmations). Failing that, slower QRSS30 or one of the weak signal digital modes such as JT9 / WSPR which have the ability to dig deep (-30db) into the background noise may be the answer ... there is much to learn yet!

Steve McDonald, VE7SL, is a regular contributor to AmateurRadio.com and writes from British Columbia, Canada. Contact him at [email protected].

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Weekly Propagation Summary – 2016 May 16 16:10 UTC

16 May 2016 | by Tomas NW7US | Leave a Comment (0)

Here is this week’s space weather and geophysical report, issued 2016 May 16 0334 UTC.

Highlights of Solar and Geomagnetic Activity 09 – 15 May 2016

Solar activity was low and only C-class flare activity was observed. Region 2543 (S05, L=002, class/area=Dao/90 on 10 May) produced a C7 flare at 14/1134 UTC which was the largest event of the period. Region 2544 (N21,L=296, class/area=Dao/150 on 15 May) produced five low-level C-class flares on 15 May, the largest being a C1 at 15/0502 UTC. Region 2542 (N12, L=357, class/area=Dai/150 on 09 May) produced a long-duration C3 flare at 15/1603 UTC with an associated filament eruption and partial-halo coronal mass ejection (CME) that departed off of the west limb. Forecaster analysis and WSA/Enlil modelling determined that the CME did not have an Earth-directed component. There were no Earth-directed CMEs during the period.

No proton events were observed at geosynchronous orbit. However, a slight enhancement was observed on 15 May associated with a long-duration C3 flare and filament eruption near Region 2542. A peak flux of 2 pfu was observed on 15 May at 2315 UTC.

The greater than 2 MeV electron flux at geosynchronous orbit was at very high levels from 09-13 May due to the influences of a negative polarity coronal hole high speed stream (CH HSS). High levels were observed on 14 May and moderate levels rounded out the week on 15 May.

Geomagnetic field activity was at unsettled to G3 (Strong) geomagnetic storm levels on 09 May due to the residual effects of a co-rotating interaction region and subsequent negative polarity coronal hole high speed stream (CH HSS). Mainly quiet to unsettled conditions were observed for 10-14 May with a nominal solar wind. A positive polarity CH HSS became connected with Earths magnetic field on 15 May causing quiet to active conditions.

Forecast of Solar and Geomagnetic Activity 16 May – 11 June 2016

Solar activity is expected to be at very low (B-class flares) to low (C-class flares) levels throughout the outlook period.

No proton events are expected at geosynchronous orbit.

The greater than 2 MeV electron flux at geosynchronous orbit is expected to be at high levels on 16-23 May, 30 May-02 Jun, and 06-10 Jun. Moderate flux levels are expected for the remainder of the period.

Geomagnetic field activity is expected to reach G1 (Minor) geomagnetic storm levels on 16, 19-20 May due to the influence of recurrent positive polarity coronal hole high speed streams (CH HSS). G1 (Minor) storm levels are also expected on 29 May and 04-05 June due to the influnce of negative polarity CH HSSs.

Don’t forget to visit our live space weather and radio propagation web site, at: http://SunSpotWatch.com/

Live Aurora mapping is at http://aurora.sunspotwatch.com/

If you are on Twitter, please follow these two users: + https://Twitter.com/NW7US + https://Twitter.com/hfradiospacewx

Get the space weather and radio propagation self-study course, today. Visit http://nw7us.us/swc for the latest sale and for more information!

Check out the stunning view of our Sun in action, as seen during the last five years with the Solar Dynamics Observatory (SDO): https://www.youtube.com/watch?v=zXN-MdoGM9g

We’re on Facebook: http://NW7US.us/swhfr

Visit, subscribe: NW7US Radio Communications and Propagation YouTube Channel

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Listen to the music

15 May 2016 | by Richard AA4OO | Leave a Comment (0)

Comparing CW audio

The Elecraft KX3 and the Ten-Tec Eagle

The bands were very poor today from my home and finding stations to operate were few and far between, especially at QRP power. So I thought I'd take a break from operating and create a brief video demonstrating the CW audio differences between the Ten-Tec Eagle and the Elecraft KX3.

The radios

The Elecraft KX3 and Ten-Tec Eagle don't have much in common apart from having DSP architectures and both being from American radio manufacturers. The Eagle is devoid of bells, whistles and has no-menus. On the Eagle, what you see is all you get, as opposed to the KX3 which has multiple kitchen sinks stuffed into it's tiny enclosure.

Setup

Both radios have their pre-amps off and DSP bandwidth set to 500 Hz. I have the RF gain reduced by about 15dB on each radio since turning up the RF gain on a noisy day like today just makes for white noise.

During the video I operated the NR (noise reduction) button on the Eagle to demonstrate how it makes a signal pop and in the same manner operate the APF (audio peaking filter) on the KX3. I end the demonstration by reducing the DSP bandwidth down to about 100 Hz on each radio. The Eagle has both 600 Hz and a 300 Hz IF filters so it gets a bit of insertion loss when I pass through the 300 Hz setting. There were no adjacent signals so the IF filtering wasn't doing anything for either radio in this case.

The audio from the Eagle is coming from its built-in speaker, while on the KX3 I'm using an iHome external, self-powered, speaker. The KX3 has an abysmal internal speaker and there's little point in trying to listen to it compared to a radio with a real speaker. In my opinion that speaker is one of the few serious flaws in the KX3.

After I shot the video I realized that there was a bit of a bias against the Eagle's audio because the microphone in the camera was below the top of the Eagle's case and thus wasn't directly hearing the cabinet speaker, whereas it was in direct view of the external speaker connected to the KX3. The Eagle's audio sounds crisper than this in person when your ears have a straight shot to the speaker.

Subjective listening

Audio is a very subjective thing because people can hear the same thing very differently so I won't comment on my opinion on which I prefer.

I would however be curious to hear other's opinions.

That's all for now

So lower your power and raise your expectations

73/72

Rich, AA4OO

http://hamradioqrp.com

Richard Carpenter, AA4OO, is a regular contributor to AmateurRadio.com and writes from North Carolina, USA. Contact him at [email protected].

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ICQ Podcast Episode 211 – Emergency Comms

15 May 2016 | by Colin M6BOY | Leave a Comment (0)

In this episode, Martin M1MRB / W9ICQ is joined by ED Durrant DD5LP, Dan Romanchik KB6NU, Chris Howard M0TCH and Martin Rothwell M0SGL to discuss the latest Amateur / Ham Radio news. Colin M6BOY rounds up the news in brief, and this episodes feature is - Emergency Comms

Young US Ham wins at Science and Engineering Fair
ARRL Committee Conducting Youth in Amateur RadioSport Survey
UK Advanced Radio Exam 'on demand'
Netherlands to Licence Low-Power AM Broadcasters
RSGB Examination Standards 1st Report
Hara Arena in Consideration for New Fairgrounds
UK Air Cadets 5MHz Radio Exercise
Online Australian Ham Licence Lookup Service
Robotic Lawn Mower EMC Banned in Sweden

Colin Butler, M6BOY, is the host of the ICQ Podcast, a weekly radio show about Amateur Radio. Contact him at [email protected].

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ICQ Podcast Episode 211 – Emergency Comms

15 May 2016 | by Colin M6BOY | Leave a Comment (0)

Young US Ham wins at Science and Engineering Fair
ARRL Committee Conducting Youth in Amateur RadioSport Survey
UK Advanced Radio Exam 'on demand'
Netherlands to Licence Low-Power AM Broadcasters
RSGB Examination Standards 1st Report
Hara Arena in Consideration for New Fairgrounds
UK Air Cadets 5MHz Radio Exercise
Online Australian Ham Licence Lookup Service
Robotic Lawn Mower EMC Banned in Sweden

Colin Butler, M6BOY, is the host of the ICQ Podcast, a weekly radio show about Amateur Radio. Contact him at [email protected].

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AmateurLogic 90: Everybody’s Talking About Antennas

15 May 2016 | by George W5JDX | Leave a Comment (0)

AmateurLogic.TV Episode 90 is now available for download.

Tommy’s Antenna Hanging. Emile’s Wet Noodle. Peter has a free antenna reference. George builds the Hula Loop.

Plus viewer email and more.

1:02:10

Download
YouTube

George Thomas, W5JDX, is co-host of AmateurLogic.TV, an original amateur radio video program hosted by George Thomas (W5JDX), Tommy Martin (N5ZNO), Peter Berrett (VK3PB), and Emile Diodene (KE5QKR). Contact him at [email protected].

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