Calibrate Receive Audio for Ham Radio Soundcard Digital Modes

April 24, 2016 Jeffrey Kopcak

This tutorial will show to determine an optimal Receive Volume (RX) level on your audio interface for operating (or only receiving) digital modes. My tutorial showing how to setup your audio interface in Windows is the starting point for this tutorial. Please review it, specifically the “Recording” settings as this tutorial builds upon it including having an existing audio interface setup.

The audio level from the radio into the audio interface is typically a fixed level. Once the audio enters the audio interface, the level sent to the computer is adjustable by the RX or Receive Level controls. This tutorial will help determine the optimal setting for the RX level.

Soundcard Oscilloscope is a program that emulates an oscilloscope from signal data received from a sound card. The radio will need to monitor active digital transmissions. Tuning to HF frequencies where PSK31 (7.070/14.070), JT65 (7.076/14.076), or RTTY (7.080-7.125/14.080-14.100) transmissions can be observed are great places. The 40 and 20 meter frequencies for those are listed as those bands are more active.

This tutorial can help set the transmit level of another station by observing or monitoring their transmissions. Do this only after you’ve calibrated your receive audio and spent a good amount of time operating with no audio issues of your own. Use a quiet simplex frequency both can hear the other station. This way adjustments will not be effected by other stations on the same sideband frequency. FM won’t matter because only one station can occupy the frequency at a time.

A similar tutorial appeared in QST recently. They beat me to it, lol!

Program versions

Windows 7 – 64 bit
Soundcard Oscilloscope 1.46

Download and Installation

This will install Soundcard Oscilloscope on your PC.

Go to https://www.zeitnitz.eu/scope_en.

Click the link to “Download the latest version.” Save it in your Downloads folder.

Launch the installer.

Click Yes.

Click Next.

Installation will begin.

Click OK.

Click Finish.

Soundcard Oscilloscope is now installed.

Configuration

This will setup Soundcard Oscilloscope to capture audio coming from your audio interface device.

Start Soundcard Oscilloscope by clicking the Start orb.

Click All Programs.

Click Scope.

The first time the program is run, you’ll be prompted to select a language. Select your language and click Continue.

The program is not free and will ask for a License key. Not entering a license will display this screen each time the program is started. The program is less than $12.50 US. Please support the developers by purchasing a license. This is made at the download site by clicking the “private donation license” link.

Click Continue if you don’t have a license.

Click the Settings tab.

Under Windows Sound Parameters, Audio Devices, Input is where you select the audio interface device. For SignaLink USB, this would be Microphone USB Audio Codec. Other interfaces: Line In, or Mic In would be selected appropriately and known from my audio interface setup tutorial.

Soundcard Oscilloscope is now configured.

Setting receive level audio

These screenshots will help determine optimal audio RX setting for receive audio. It is important to leave the audio level settings alone in Windows. These settings were shown in my audio interface setup tutorial. Adjust the settings in Windows ONLY when where is not enough audio when RX level is at the maximum setting or there is too much audio with RX set to the lowest setting.

Click the Oscilloscope tab if you are not there already.

These settings will need to be reset after restarting the program. At this point, my radio is off but it doesn’t matter.

Set the Amplitude to 250mv.

Set Time to 10ms or less.

Turn on the radio if it is not already.

Examples

Adjust the RX level until there are no peaks with flat-tops on the oscilloscope. Flat-tops indicate the audio level is too high and digital programs will have a hard time decoding the signal. These examples were taking monitoring PSK31 on 20 meters.

This is the best example. No flat-top peaks. Peaks appear about two divisions from the center line. There is plenty of headroom for louder signals. My RX setting was about the 10 o’clock tick-mark on my SignaLink.

Anything lower than two divisions will still work. There maybe issues pulling out weaker stations.

Here is a good example but I would not be comfortable with this audio level. The peaks do not have flat-tops which is good. However, the peaks are reaching well into the third division. My RX setting was about the 11 o’clock tick-mark on my SignaLink.

This is an example of what the scope should not look like. Peaks have flat-tops at the fourth division. The audio level is too high into the computer and RX volume needs to be dialed back. My RX setting was about the 1 o’clock tick-mark on my SignaLink.

When optimal level is reached, the audio interface receive audio level is calibrated!

Amateur Radio, ARRL Ohio Section, Computing, Ohio Section Journal

Ohio Section Journal – The Technical Coordinator – April 2016 edition

April 18, 2016 Jeffrey Kopcak

One of the responsibilities of the Technical Coordinator in the Ohio Section is to submit something for the Section Journal. The Section Journal covers Amateur Radio related things happening in and around the ARRL Ohio Section. It is published by the Section Manager Scott – N8SY and articles are submitted by cabinet members.

Once my article is published in the Journal, I will also make it available on my site with a link to the published edition.

You can receive the Journal and other Ohio Section news by joining the mailing list Scott has setup. You do not need to be a member of the ARRL, Ohio Section, or even a ham to join the mailing list. Please sign up!

If you are an ARRL member and reside in the Ohio Section, update your mailing preferences to receive Ohio Section news in your inbox. Those residing outside the section will need to use the mailing list link above.
Updating your ARRL profile will deliver news from the section where you reside (if the leadership chooses to use this method).
Go to www.arrl.org and logon.
Click Edit your Profile.
You will be taken to the Edit Your Profile page. On the first tab Edit Info, verify your Email address is correct.
Click the Edit Email Subscriptions tab.
Check the News and information from your Division Director and Section Manager box.
Click Save.

Now without further ado…

Read the full edition at: http://n8sy2.blogspot.com/2016/04/april-edition-of-ohio-section-journal.html

THE TECHNICAL COORDINATOR
Jeff Kopcak – TC
k8jtk@arrl.net

Hey Gang,

So — Windows 10. This topic was brought up during the after meeting at my local club. Many of you are undoubtedly seeing the upgrade nag-screens. You too might be wondering: what’s changed in Windows 10, might have heard some of the issues surrounding the new operating system, and why the big push to upgrade. This month I’ll cover the new operating system from the perspective of what has happened so far and not from a ham radio perspective. Also to preface this whole thing, Microsoft has never been very clear about their statements and often retracts or goes back on things they’ve said. In other words, any of this may change as we go along.

What is Windows 10?… why not Windows 9? There are many theories surrounding the choice in numbering. The named version of Windows hasn’t matched the real version number since Windows NT 4.0. Windows 10 is the successor to Windows 8.1, but not Windows as you know it. It represents a shift in the direction of Microsoft as a company. Microsoft indicated this is the “the last version of Windows.” While they’re not killing it off, Microsoft is moving to a model they call “Windows as a service.” This means Microsoft will deliver innovations and updates in an ongoing manner instead of separate releases (versions) of Windows. The ultimate goal is to have one version of Windows that will run on all platforms. Everything, including Raspberry Pi, phones, tables, HoloLens (wearable, so called “smart-glasses”), laptops, desktop PCs, Surface Hubs (interactive whiteboards), and Xbox entertainment systems. Having one version of an operating system means all of these systems will become integrated and share information easily.

A large part of this shift includes the use of “the cloud.” The cloud is a fancy term for someone else’s equipment on the Internet. The most common example is ‘cloud storage.’ Services like DropBox, Google Drive, or OneDrive allow you to save your documents and pictures elsewhere. You upload files to these services and you can access those files or share them with others on the Internet. The cloud is heavily integrated into Windows 10. After installing Windows 10, it will prompt you to sign in using a Microsoft Account. This syncs your user profile with the Microsoft cloud. When you sign into another device using your Microsoft Account, your settings will be the same across those devices. You can use Windows 10 without a Microsoft account. The computer will operate in standalone mode similar to previous versions of Windows. Microsoft’s online storage service called OneDrive is integrated into the operating system as well. Other new features include your new personal assistant, Cortana. She will help find things on your computer and the web, set reminders, similar to Apple’s Siri or Google Now.

Universal apps: These first appeared in Windows 8 as “Metro Apps.” This concept is to have developers write one application and have it work the same way on any Windows platform. These apps are found and delivered via the Microsoft Store (similar to the Android Play Store or Apple’s App Store), and again – available on all platforms. Some games and applications that came preloaded in previous versions of Windows have been replaced with Universal Apps in 10.

Edge browser: Microsoft Internet Explorer has been replaced with Microsoft Edge. It’s been touted as a more secure browser. However, this has yet to play out because browser extensions are very limited.

Free upgrade: Legal copies of Windows 7/8/8.1 are eligible for a free lifetime upgrade to Windows 10 until July 29, 2016. There are some stipulations to this free upgrade. “Lifetime” means the lifetime of the device eligible for the free upgrade. When that device fails, you cannot transfer the free upgrade to another device. What happens after July 29th? Microsoft hasn’t said. The free upgrade is expected to become a premium upgrade that you’ll have to purchase, even for a device that was previously eligible for the free upgrade. Versions prior to Windows 7 are not eligible for the free upgrade. To be honest, if you’re running a version of Windows prior to 7, you probably want to upgrade your hardware for 10.

Now reality.

Big upgrade push: Windows users have seen the icon in the system tray nagging them to upgrade. Why the big push? Microsoft is trying to avoid another Windows XP. At the time Windows XP was declared “end-of-life,” it accounted for about 10% of all computers on the Internet. Two years later, about 7% are still using XP. That’s a lot of users running a dead operating system. On top of that, Windows 7 will be 7 years old in July and only supported for 4 more years (until January 2020).

While Windows XP maybe working great, there are reasons to get off of it. Google has been leading a push for a more secure Internet. Windows XP cannot handle many modern security methods in use today. All browsers in XP (except Firefox) will display ‘your connection is not private’ when connecting to a website that has more modern security then XP can understand. Since Windows XP is not a supported operating system, it won’t be updated to handle modern security methods. While the website will still work, your connection will be less secure. A work around for this security issue is to use Firefox. Though no known vulnerabilities exist in XP, best practice dictates users should remove unsupported operating systems from the Internet if it doesn’t need to be on the Internet. Another reason to upgrade is new hardware and software will not have support for old operating systems.

The upgrade push for Windows 10 has been nothing short of a disaster. Last year, users eligible for the upgrade began seeing a Windows icon in the system tray saying ‘you’re PC is ready for your free upgrade.’ This deplorable tactic is commonly used by malware and spyware authors to trick you into installing software you don’t want or need. As an Information Technology professional with an interest in cyber security, this is the type of message I tell users NOT to acknowledge. Kind of ironic. Initially this tray icon came in the form of a Windows “Recommended” update. Then Microsoft upgraded it to a “Critical” Windows Update -yet another deplorable tactic. Despite this maneuver, Windows 10 is NOT a critical update. The upgrade popups are very confusing as the clickable options are: “upgrade now,” “upgrade later,” “OK,” or “Get Started.” Oh, it gets worse. Users are reporting they vigilantly closed the prompts to upgrade (clicked the red “X”) but their system was still upgraded automatically against their wishes. They went to bed with Windows 7 and got up the next morning to Windows 10. Surprise.

Once the upgrade happens, you do have 30 days to revert back to your previous version of Windows. The problem here is users have found the roll back frequently fails. Imagine that. ‘Don’t worry, you can go back… if you want. Opps, the roll back just failed! Guess you’re stuck.’ Thanks.

Start Menu: Microsoft tried to remove the Start menu in Windows 8 and replaced it with a full screen tile menu. This was an attempt start a unified experience between PCs and mobile devices. The change worked fine on small screen devices but was a terrible experience on PCs. It was met with much outcry. The Start menu has returned in Windows 10 with something that kind of resembles the Start menu from Windows 7. It’s more of a combined Start menu — “Live Tile” experience. Live Tiles display updates like weather, news, and photos, while others are just a static application icon.

Adding to the confusion, there now two places where system settings reside: “Settings” and “Control Panel.” Settings typically run between devices like time zone, personalization, notifications, and user accounts. The Control Panel is mostly desktop specific settings.

Tracking: Microsoft Windows 10 tracks much of what you do and where you go. Their claim is they provided a free upgrade so you can give some information back to Microsoft on your usage. Two problems with this: even if you pay for the Windows 10 upgrade, this information is still shared with Microsoft. The other, this tracking is now rolled into Windows 7 and 8. Privacy advocates feel this is a violation of user’s privacy. The argument on the other side is most use Google or Apple’s services and they know just as much about you. This Ars Technica article explains tracking is a growing trend in technology: http://arstechnica.com/information-technology/2015/08/windows-10s-privacy-policy-is-the-new-normal/

Upgrade tips: create a full system backup using a backup service or create an image of your current installation on an external hard drive before attempting to upgrade. This is a backup incase the rollback fails. Check the vendor’s website of your hardware and critical software applications. Look for driver support or knowledge base articles about Windows 10 before upgrading. Knowing whether your devices and software are supported will help minimize regret because your favorite app or device no longer works.

Certainly some of these concerns have caused me to look at alternative operating systems. I have found in my deployments (I have yet to upgrade all of my desktops) with a little work, I can get 10 to act a lot like (my favorite) Windows 7. Turning off or uninstalling cruft helps a lot: turning off notifications, disabling camera & microphone usage, disable Cortana, remove many Universal Applications, and turn off background apps. I use Classic Shell to return a normal looking Start menu and Anti-Beacon to disable tracking. Links to those applications and ones to disable the upgrade nag-screens are below. Seriously, if you find any of these apps useful, consider donating to the author because we need to support those doing the right thing and allowing choice.

Thanks for reading and 73… de Jeff – K8JTK

Image sources: thurrott.com, zdnet.com, and blogs.windows.com.

As always, use these at your own risk.
Disable Windows 10 upgrade and notifications in Windows 7 & 8/8.1:
Never 10: https://www.grc.com/never10.htm
GWX Control Panel (advanced users): http://ultimateoutsider.com/downloads/

Start menu replacement for Windows 8 & 10:
Classic Shell: http://www.classicshell.net/
Start 10 (trial): http://www.stardock.com/products/start10/

Disable Windows tracking:
https://github.com/10se1ucgo/DisableWinTracking
https://www.safer-networking.org/spybot-anti-beacon/ (from the makers of SpyBot Search and Destroy, works on all versions of Windows).
A more manual approach is presented: http://arstechnica.com/information-technology/2015/08/windows-10-doesnt-offer-much-privacy-by-default-heres-how-to-fix-it/

Amateur Radio

SSTV Transmissions from the International Space Station – April 2016 edition

April 14, 2016 Jeffrey Kopcak

An ARISS Commemorative SSTV Event Set for April 11-14 recently concluded. This event was longer than usual and I received alot of pictures. Check the ISS tag for my other ISS SSTV posts.

Station setup: MP Antennas Classic Mobile NMO Antenna – This is a local company in Cleveland and were reviewed in QST. Been using their antennas for a long time with great success. Since the antenna is multi-polarized (the MP in the company name), it is supposed to be a good substitution for receiving satellite transmissions without a directional antenna and not worrying about Doppler Shift (which needs to be accounted for in some cases). The height is about 15 feet.

The antenna was connected to my ICOM IC-7000 with DSP settings turned off on 145.800 MHz FM. Used this radio only because my SignaLink USB is connected to it and the one I use for digital operation on all bands. MMSSTV is the Slow-Scan TV program I use.

I have tutorials available to help get your station setup and getting started with MMSSTV to receive images from the ISS.

I received 14 images total from my location near Cleveland (EN91bl).

SSTV-Transmissions-from-the-International-Space-Station-2016-04-12-1959 — 2016-04-12 1959 UTC

SSTV-Transmissions-from-the-International-Space-Station-2016-04-12-2004 — 2016-04-12 2004 UTC

SSTV-Transmissions-from-the-International-Space-Station-2016-04-12-2138 — 2016-04-12 2138 UTC

SSTV-Transmissions-from-the-International-Space-Station-2016-04-12-2315 — 2016-04-12 2315 UTC

SSTV-Transmissions-from-the-International-Space-Station-2016-04-13-0051 — 2016-04-13 0051 UTC

SSTV-Transmissions-from-the-International-Space-Station-2016-04-13-0230 — 2016-04-13 0230 UTC

SSTV-Transmissions-from-the-International-Space-Station-2016-04-13-0404 — 2016-04-13 0404 UTC

SSTV-Transmissions-from-the-International-Space-Station-2016-04-13-1907 — 2016-04-13 1907 UTC

SSTV-Transmissions-from-the-International-Space-Station-2016-04-13-2046 — 2016-04-13 2046 UTC

SSTV-Transmissions-from-the-International-Space-Station-2016-04-13-2222 — 2016-04-13-2222 UTC

SSTV-Transmissions-from-the-International-Space-Station-2016-04-14-0000 — 2016-04-14 0000 UTC

SSTV-Transmissions-from-the-International-Space-Station-2016-04-14-0139 — 2016-04-14 0139 UTC

SSTV-Transmissions-from-the-International-Space-Station-2016-04-14-0312 — 2016-04-14 0312 UTC

SSTV-Transmissions-from-the-International-Space-Station-2016-04-15-1859 — 2016-04-15 1859 UTC

Amateur Radio, ARRL Ohio Section, Ohio Section Journal

Ohio Section Journal – The Technical Coordinator – March 2016 edition

March 16, 2016 Jeffrey Kopcak

Once my article is published in the Journal, I will also make it available on my site with a link to the published edition.

Now without further ado…

Read the full edition at: http://n8sy2.blogspot.com/2016/03/march-edition-of-ohio-section-journal.html

THE TECHNICAL COORDINATOR
Jeff Kopcak – TC
k8jtk@arrl.net

Hey Gang,

It’s been a busy month for yours truly. Things got started off with a drive down to Columbus with my dad N8ETP. We visited the Columbus Radio Enthusiasts Society (CRES) on February 16th. It was touch-and-go for a while due to the weather. Snow hit both areas the night before and hoped it would hold off for the meeting. It did. We made it there and back, no problem. It was our first meeting in Columbus and we couldn’t have had a better time. I was contacted by Steve – N8WL to troubleshoot an RFI issue he was experiencing. We got to talking and he invited me to come down and speak about, well, myself –what the Technical Coordinator does and projects I’ve worked on. The presentation consisted of: my history in Ham Radio and how I got to where I am, laid out the ARRL and Field Services structures, section level positions and the Ohio Section, my responsibilities as Technical Coordinator, and projects I’ve worked on. In addition gave some pointers for troubleshooting RFI problems. Our Section Manager was on hand and helped answer specific questions about the section. It was an informative meeting. CRES: http://www.w8zpf.net/, presentation: http://www.k8jtk.org/2016/02/16/about-the-arrl-ohio-section-technical-coordinator/

The following weekend I presented at the Mansfield Hamfest during the Digital Forum. Danny – W8DLB, who is in charge of the Hamfest, was at my NBEMS training session in Medina County and asked me to present it during the Digital Forum. The Digital Forum covered voice and text based digital modes. Duane -K8MDA demonstrated FreeDV. FreeDV is a mode used on HF for voice communication. It’s impressive because the bandwidth is about one-third of sideband! I gave a portion of my training session on Narrow Band Emergency Messaging using Fldigi.

At the LEARA meeting in Cleveland, I showed the video for the Navassa Island K1N DXpedition which happened in February of last year. A DXpedition is an expedition to a remote location, usually uninhabited, for the purposes of activating the location and making as many contacts as possible. Navassa was my first time trying to chase a “most wanted” entity for my log. I was able to log them twice. Bob Allphin – K4UEE has participated in many DXpeditions and has released the story of many on DVD. I had no idea what it took to put on a DXpedition of that magnitude. After seeing his DVD on Navassa, I now have a better idea. It is a phenomenal video that got rave reviews and comments at the meeting. The main video runs about 45 minutes. The wrap-up from the Dayton forum is included which has some great background details. These are great for club meetings, introducing newcomers to Ham Radio, and gifts. Purchasing the video helps supports future DXpeditions and supports other hams: http://t-rexsoftware.com/k4uee/dvds.htm

Last, and certainly not least, Ken – KG8DN instructor at Gilmour Academy in Gates Mills, Ohio has been in charge of the Gilmour Academy Radio Club – ND8GA for as long as I’ve known him. During the school year, organizations are in charge of running Convocation for a week. This is a gathering of the entire school for announcements, happenings, events, and entertainment. Ken asked me to speak at Convocation one morning. This was a different type of presentation than I was expecting. I figured I would be there to talk-up Ham Radio and get kids interested. Nope. It was more about life experiences with a little Ham Radio sprinkled in. Things students could relate to. I have to be honest this was more challenging than I anticipated. A lot of time was spent searching for topics that students would care about, relate to, and how those experiences got me to where I am now. There was a visual portion which included many pictures from my high school years. When looking back on friends and people I shared those experiences with, it make me wish I was back in that time. I’m sure I’ll feel the same way when I look back on today. The presentation turned out great and I have to thank Ken for all of his help. ND8GA: https://sites.google.com/a/gilmour.org/gilmour-amateur-radio-club/

Thank you to everyone for coming to my various appearances and the organizers for asking me to speak with your organizations.

I received an email from a fellow Trustee of LEARA, Marv – W8AZO, asking if I had seen my name mentioned in a post on a website. I had not. What website did he find my name on? The IEEE website. Now, I know the fine folks over at IEEE (Institute of Electrical and Electronics Engineers) are wicked smart. Much smarter than I am. They come up with solutions to technical problems which usually turn into established standards. Additionally, they publish one-third of the world’s technical literature. Why the heck would they be talking about me? Stephen Cass – KB1WNR, Senior Editor for the IEEE Spectrum magazine wrote an article titled “Hands on: A Ham Radio for Makers.” He built an FM transceiver using an RS-UV3 transceiver board and Raspberry Pi to take advantage of digital modes. I was mentioned because Stephen used the instructions I posted to compile and run Fldigi on the Raspberry Pi. Super cool! I emailed Stephen and thanked him for the plug. He was very appreciative of the well written instructions. His article may have glossed over some important points relevant to hams but the goal of the article was to draw others in from the wider community. The article will be in the March printed edition of IEEE Spectrum and should be available by the time you read this. It hasn’t hit the shelves in my local bookstore yet. Online version: http://spectrum.ieee.org/geek-life/hands-on/hands-on-a-ham-radio-for-makers

That is what ham radio and makers are all about. I wanted to figure out how to run Fldigi on the Raspberry Pi, came up with a way to do it, documented it thoroughly, and shared it online. Stephen came across my instructions and used them as part of his project to create something greater; perpetuating the cycle.

Thanks for reading and 73… de Jeff

Computing, Tutorials

Bridge a Remote Site Network with OpenVPN Access Server

March 8, 2016 Jeffrey Kopcak

Having access to your devices over the Internet is a requirement for any admin deploying a project. Instead of running to a remote site to administer devices (making changes, applying updates and patches), it’s easier to connect remotely and make changes. Remote access poses many issues and concerns.

Security

First and foremost is security. You always, always, ALWAYS want devices connected to the Internet behind a router with a built-in firewall (NAT router). A firewall filters traffic between two networks (your ISP and home for example) and will block attempts to connect to your internal (private) network.

Device manufacturers take security for granted. Little testing and auditing takes place because the analysis is expensive for throw-away devices. This is noted in many stories including Bug Exposes IP Cameras, Baby Monitors where simply clicking “OK” on the login dialog allowed access to the Internet connected video camera. It is trivial to find these devices on the Internet because of Shodan. Shodan is dubbed the “Internet of Things Search Engine.” If you’re not familiar, think of it as the Google for devices connected directly to the internet. These could be: web servers, printers, cameras, industrial machines, bitcoin mining… Putting devices behind a firewall minimizes the risk because anything trying to peer into the network would be blocked by the firewall.

This holds true for networks you don’t control (granted access on someone else’s network). Put your stuff behind a router/firewall so they can’t see your devices and you can’t be exploited by devices on the other network.

Port Forwarding is a popular technique to only allow traffic on a specific port to a device you specify in your firewall (router). This provides little security as it still allows a potentially vulnerable service to accept incoming connections from the Internet.

Choose a good router

Couple of tips for a good router:

You get what you pay for. Don’t opt for cheap.
Opt for ones that support third-party firmware like DD-WRT and Tomato or setup a dedicated computer running pfsense or Untangle. These have proven to be more secure than stock firmware in addition to offering a more complete feature set.
Stick with popular models as found on Amazon, Newegg, or other tech store. They’re more likely to be reliable, well updated models.
Look for ones that accept USB cellular modem dongles for installations that have no accessible network connection like a remote site.

Virtual Private Network

The preferred way to connect to a remote network is to use a VPN. A VPN connects to a private network securely over the Internet. It allows the user to exchange data, use services, and connect to devices as if they were directly connected to that network. An open-source project that implements VPN technologies security is OpenVPN. OpenVPN is an application that allows for secure point-to-point communication. There are many implementations of OpenVPN including using it in many third-party router firmware (mentioned above). OpenVPN Access Server is one of the many implementations and the one used for this project.

This project was inspired by Hak5 1921 – Access Internal Networks with Reverse VPN Connections. As an Amateur Radio operator into the newer computer and digital technologies, more devices are located at remote sites.

This setup consists of:

A remote network behind a firewall where devices exist you want to access. This will be a Linux server on the remote network that will act as the gateway and persistently connected to the bridge. This could be a full desktop computer purposed for something else or Raspberry Pi. Also on the same network will be a Windows machine.
An unsecure/unknown network, AKA the Internet.
A private server that will act as the bridge between the remote network and a device you choose.
A device in a separate location that will connect to the cloud server and will be able to access the remote network. I will use a Windows machine to act as a ‘home’ computer.

This setup works in nearly all cases because the only device receiving incoming connections is the bridge server in the cloud. Firewalls block incoming connections by default. Very few block connections originating inside the network out to the Internet (egress). If a device along the way filters by content, connection attempts will be blocked. Many corporate networks are doing this kind of filtering. Otherwise the traffic looks the same as secure web traffic on port 443. No port forwarding is used.

Hosting

I recommend using an infrastructure hosting provider for the bridge server. This can cost anywhere from $5-$15 per month. The device can be anywhere on the public Internet. It must accept multiple connections on different ports but only by a couple users at a time are needed. Minimal configuration is more than sufficient. Bandwidth, latency, and up-time of all points in this setup effect reliability. My personal recommendations for infrastructure hosting providers are: Rackspace and DigitalOcean.

IP addressing

All remote networks and the home user networks cannot overlap in address space. That is they need to be differently numbered. For example, typically home networks have addressing as 192.168.1.x. The remote site(s) can’t have the same numbering (192.168.1.x). It must be different. I suggest making the remote site different enough to not cause conflict with any home users’ networks. Remote sites as 192.168.25.x, 192.168.26.x, and 192.168.27.x would work fine when the home users’ networks is addressed 192.168.0.x, 192.168.1.x, 192.168.2.x, and so on (except 25-27). Similarly addressed networks create routing conflicts and the packets will not reach the correct network.

Downsides

Cost.

In addition to hosting, a downside to using OpenVPN Access Server is licensing. While OpenVPN is Open-Source Software and OpenVPN Access Server is free, the license allows for only two concurrent tunnel connections at any one time. This means the remote site counts as one connection and the home device the second. If a second person (third device) needed access to the remote network, they would get a message saying ‘Access Server has reached its concurrent connections limit.’ The first person would need to disconnect first before the second could connect otherwise current connections will begin to be booted. Additionally, connecting two or more remote sites and a home user is not possible without purchasing licenses or running an additional bridge server. Additional licenses can be purchased for “$9.60 License Fee Per Client Connection Per Year. Support & Updates included. 10 Client minimum purchase.” $96 per year.

An alternative to OpenVPN Access Server is to setup your own (roll your own) OpenVPN server which is free. I hope to do an OVPN server setup at some point in the future.

Assumptions

This guide is step-by-step in nature, meant for beginners, with brief explanations of the steps. It will help to have an understanding of Linux commands and scripting. Capitalization is important in Linux! Understanding of basic networking concepts including determining network prefixes and CIDR notation is also required.

Program versions

I used a Windows 7 64 bit PC for configuration (and Home PC). Applications and versions used in this writeup:

OpenVPN Access Server 2.0.24
Putty 0.67
Ubuntu 14.04 x64 (bridge and remote servers)
Filezilla 3.16.0

Pages: 1 2 3 4 5 6 7

Amateur Radio, ARRL Ohio Section, Ohio Section Journal

Ohio Section Journal – The Technical Coordinator – February 2016 edition

February 16, 2016 Jeffrey Kopcak

Once my article is published in the Journal, I will also make it available on my site with a link to the published edition.

Now without further ado…

Read the full edition at: http://n8sy2.blogspot.com/2016/02/february-issue-of-ohio-section-journal.html

THE TECHNICAL COORDINATOR
Jeff Kopcak – TC
k8jtk@arrl.net

Hey Gang,

I was contacted this month by someone concerned that Fldigi would install a “trojan” on their computer and wanted to know where to get a clean download of the program. Before panic sets in, there is no reason to smash your hard drives. Why did I receive this question? I’ll explain the tech behind the issue.

The place that Fldigi, Flmsg, Flrig, and all other applications are now hosted is at a place called SourceForge (also abbreviated “SF”). SourceForge is a web service launched in 1999 that offers tools for developers to manage their projects for free. They host source code (for those who wanted to read, audit, modify, or learn from raw code), web pages for the project, mirrors (hosting in multiple locations in case any-one server is down), bug tracking, and many other features. It was the place for hosting free and open-source software. A ton of very well-known projects were (some still are) hosted on SourceForge: Apache Server, GIMP, OpenOffice, Firefox, Thunderbird, Audacity, Filezilla, Drupal, WordPress, JT65-HF… list goes on.

Some users were discouraged by the number of advertisements on the site. Though it is an ad-supported free service, there weren’t any viable alternatives.

In July 2013, SourceForge created an optional service available to developers called “DevShare.” Any developer who participated in the service would knowingly push additional unwanted programs to anyone downloading their project. This is commonly referred to as ‘crapware’ encompassing adware, download managers, antivirus programs, browser toolbars, homepage modifications, search engine replacements, and the like.

In May 2015, it was reported that SourceForge seized control of what they considered ‘deprecated or abandoned’ Windows projects. In taking control, they locked out the developer and “updated” project downloads to push similar ad-supported content.

This is a problem because the open-source community is just that, a community. They are made up of enthusiasts that like developing programs. Much like ham radio, they donate their time and do it for free. When a company takes the good name of a well-known project and tarnishes it by installing adware on users’ computers, this doesn’t go over well with the community. Their business practices effectively destroyed what was left of SourceForge’s reputation.

The DevShare project started a movement within the community to find replacements for SourceForge; GitHub primarily. SF since stated they are not taking control of unmaintained projects. It was too-little, too-late. Many developers deleted their projects from SF and moved their content elsewhere. It is up to each developer to make a decision about their project. I’ve provided links at the end of the article that go more in-depth for those into tech stories. SourceForge is not the only site that bundles crapware in downloads. Download sites like CNet’s Download (dot) com and many other free file hosting services also push ads and unwanted programs.

slusb Back to Fldigi. The developer of Fldigi maintained the installer and source files on his own server. Somewhere near the end of last year, his site was hacked. The decision was made to move the files from his server over to SourceForge. Likely in an attempt to be more secure.

This created a problem for many who are aware of the issues with SourceForge. Unfortunately, it is the only place where the Fldigi Suite updates and downloads reside. I have installed many Fldigi updates since the move to SourceForge and have not seen anything to suggest any unwanted programs are included. The issue is something to be aware of.

Good security practice dictates not downloading anything you-yourself didn’t go looking for. If you do download Fldigi and it is prompting you to install an antivirus program, this is a huge red flag. Another example: never click anything that says ‘your plugins, Java, Flash, antivirus, or system… is out of date’ because you weren’t looking for those updates.

In other news, I would like to welcome Technical Specialist Eldon – W5UHQ. If that sounds familiar, it’s because he is the Net Manager for the OHDEN HF digital net. The Ohio Digital Emergency Net meets Tuesday evenings at 8pm on 3585 using OLIVIA 8/500 at 1 kHz. The purpose is to provide statewide communications to EMA and EOC’s in Ohio using sound card digital modes. If that wasn’t enough, he brings an extensive background in communications and electronics to the group. OHDEN net: http://ohden.org/

I will be at the Mansfield Hamfest on February 21. I’ve been invited to present during the Digital Forum at noon. This is assuming the weather is better than it has been the last few days, hi hi. The Digital Forum will contain a presentation on digital voice by Duane – K8MDA and I will present passing messages using Fldigi. Hope to meet you at Mansfield! More: http://hamfest.w8we.org/

Thanks for reading and 73… de Jeff – K8JTK

Articles on SourceForge:

http://www.infoworld.com/article/2929732/open-source-software/sourceforge-commits-reputational-suicide.html

http://arstechnica.com/information-technology/2015/05/sourceforge-grabs-gimp-for-windows-account-wraps-installer-in-bundle-pushing-adware/

Amateur Radio, ARRL Ohio Section, Presentations

About the ARRL Ohio Section Technical Coordinator presentations

February 16, 2016 Jeffrey Kopcak

I was asked to give a presentation about the ARRL Ohio Section Technical Coordinator and projects I’ve worked on.

Framework

The framework I chose to use for the presentation slides is called reveal.js. It is an HTML framework meaning it will run in any HTML 5 capable browser. Looks a little better than a PowerPoint presentation.

Navigation

Useful navigation keys in the presentation. In addition to navigating with the keys below, you can swipe (tables/smartphones) or use the navigation arrows on screen in the lower right.

Toggle full screen: press [F11].

Advance to the next slide: press [n] or [SPACEBAR].

Go back to the previous slide: press [p] or press and hold the [SHIFT] key while pressing the [SPACEBAR].

Display presentation overview: [ESC] then use the arrow keys or mouse to select a slide. [ESC] again will exit overview mode.

Links

Clickable links are colored in blue text.

Presentations

Three variations are available: presentation version is viewable in a browser. Printable version for printing or saving in a different format (Chrome, Chromium, and variants compatible only). Finally a PDF version.

They may take some time to load because I left original images untouched and some were a couple MB in file size.

Slides

Version 3

The presentation is about 45 minutes in length.

Presentation version
Printable version
PDF version

This presentation was given at the following meetings:

Cuyahoga County ARES on 2/21/2023

Version 2

The presentation is about 45 minutes in length.

Presentation version
Printable version
PDF version

This presentation was given at the following meetings:

Lake County Amateur Radio Association on 9/4/2018

Version 1

The presentation is about 45 minutes in length.

Presentation version
Printable version
PDF version

This presentation was given at the following meetings:

Columbus Radio Enthusiasts Society on 2/16/2016

Amateur Radio, Digital Communications in Amateur Radio articles

Digital Communications in Amateur Radio: Overview

February 2, 2016 Jeffrey Kopcak

This article appeared in the The Wood County Amateur Radio Club newsletter CQ Chatter February 2016 edition.

Read the rest of the series in the Digital Communications in Amateur Radio articles category.

When I was planning my HF station a few years ago, I knew I wanted to learn more about digital modes. I was familiar with some like Slow Scan TV and Craig – NM8W told me about JT65 a couple years ago. I didn’t understand HF – let alone HF digital. I was lost and had alot to learn.

Since I’ve been on the HF bands, the large majority of my contacts are some form of digital and I’m always exploring new ones. JT65 is my current mode of choice. The perception from many hams is digital modes are foreign and complicated to setup. It takes a little understanding.

In this series of articles, I will be discussing getting on the air with digital from your station. This article will give a general overview of digital communications. Future ones will discuss setting up your station, dive into operating specific modes, and using specific applications. Much of the information will be related to HF and sideband operation. Technicians – fear not, these can be operated on VHF/UHF sideband or even FM simplex with HTs. I’ll get into important distinctions between sideband and FM next time.

I’ve been using computers from a young age. I learned applications and started programming in middle school and continued through high school. I received my undergraduate degree in Information Systems. Through most of college, I was a Technician class licensee and didn’t know much about sideband. I didn’t use computers all that much in ham radio. Most of my activities were related to other things I knew how to do, like build websites. I wasn’t logging or controlling my radio since I was using HTs most of the time.

There were a couple FM digital nets on repeaters in Cleveland that got the ball rolling for me. Slow Scan TV was the first of these modes. It was really cool seeing still pictures come across my screen with a couple audio cables. Later, a digital net for NBEMS training was formed to practice passing messages and forms for emergency communications. That net exposed me to one of the most versatile programs for operating digital modes. After college, I got into D-STAR. That integrated IP (Internet Protocol) technology, which I studied in college, and continued my interest.

Let’s start by taking about digital communications. At a basic level, digital communications is a binary representation and transfer of data (1’s and 0’s). Data is encoded into some structure (protocol, format, rate) before it is transmitted. Digital communication is a very broad term and takes many forms.

Morse Code is the most basic form of digital. The signal is either on or off (1 or 0). The on/off keying creates a series of dots and dashes to make up letters, numbers, and symbols.

Digital voice (often referred to as “DV”) is a method of taking audio from a source (microphone) and digitizing (or encoding) it into a data stream. When decoded at the receiving end, the data stream is converted back into audio and played through a speaker. Voice formats include P25, D-STAR, DMR, FreeDV, and System Fusion. Many voice formats include the ability to transmit a small amount of text at the same time. This text stream is not very fast because voice takes higher priority and the majority of the bandwidth. Text is relegated to call sign, a banner message, or GPS coordinates; things that don’t take a lot of bandwidth.

Data formats exist to transmit text or binary data. Most text based formats are keyboard-to-keyboard or chat style exchanges. Binary exchanges can be files, pictures, or documents. Data format examples are D-STAR, MT-63, MFSFK, JT65/9, Olivia, Packet/APRS, PSK31, RTTY, and System Fusion. Some formats can carry voice (mentioned earlier) but most cannot (i.e. PSK31, RTTY).

Why digital communications? The widespread ownership of personal computing devices allows amateurs to develop and use these modes for communication purposes. Many digital modes are referred to as “sound card modes” because to operate many of them requires little more than a computer, sound card, and radio. In recent years, ‘personal computing devices’ has grown to include smartphones, tablets, and micro-computers because programs have been written to use these modes on those devices.

Digital transmissions can be faster and more reliable. Faster: more words per minute can be transmitted over digital modes. They can be more reliable over greater distances, poorer conditions, and contain error correction. Error correction is the encoding of redundant data into the transmission. When errors are encountered, the redundant information can help reconstruct lost data without retransmission. Error correction helps when noise or other undesirable characteristics are introduced to a receiver. If the signal is completely lost, interrupted, or falls to the noise, no level of error correction will decode the signal. Like most things in technology, each digital mode has its intended use, advantages, and disadvantages. Not all modes fit into all categories and may not be mutually exclusive to a single category.

Next time, I will discuss considerations for your station and the interfaces that go between your computer and radio. Please contact me with questions and ideas. It will let me know what readers are interested in and modes to cover.

Amateur Radio, ARRL Ohio Section, Ohio Section Journal

Ohio Section Journal – The Technical Coordinator – January 2016 edition

January 18, 2016 Jeffrey Kopcak

Once my article is published in the Journal, I will also make it available on my site with a link to the published edition.

Now without further ado…

Read the full edition at: http://n8sy2.blogspot.com/2016/01/january-2016-issue-of-ohio-section.html

THE TECHNICAL COORDINATOR
Jeff Kopcak – TC
k8jtk@arrl.net

Hey Gang,

Happy New Year. Welcome to 2016! Hope Santa was good to you and left you a new radio under the tree. A white Christmas would be nice but I’ll take the warm temperatures we had for the holidays. I took some MUCH needed time off from work and spent it: sleeping, doing things with friends and family, operating on the radio, and watching NCIS. Got a couple hundred JT65/9 contacts in the log (really because I was slacking the last couple months and to make up for lost time!), played with Yaesu’s System Fusion, and WSPR (Weak Signal Propagation Reporting).

I hope everyone got to spend some time at their local club’s holiday parties. My family and I attended the LEARA (Cleveland) holiday meeting where I won the club’s giveaway of a new Baofeng radio and also a hat courtesy of our own Section Manager! This past weekend (Jan 10), I visited the Wood County Amateur Radio Club (Bowling Green) and attended their Kick-off banquet to begin the New Year! Great to see everyone.

I’ve been invited to visit the Columbus Radio Enthusiasts Society on February 16th. They asked me to present at their meeting on what the Technical Coordinator does and projects I’ve worked on. Stop by and say hi as it’s my first club meeting in central Ohio. More: http://www.w8zpf.net/

slusb

A couple months ago, I decided to see if I could get Fldigi working on the Raspberry Pi with my SignaLink. Fldigi is a modem application that is used for message passing or operating PSK, RTTY, and many other digital modes. I thought the tutorial could be a good resource for those who want to replace large PCs with much smaller Raspberry Pi computers or install digital in their go-kit. It was a success, or so I thought. I hit a couple snags along the way during initial testing. The first problem was a junky USB power supply. The SignaLink would key the radio for a time but would start a key-unkey sequence every second or so. I got what I paid for — use quality parts in your project. I swapped out the power supply. After that, I thought it was good to go.

Unfortunately, Ken W0KAH (from Missouri) contacted me over the holidays and said ‘it’s working great… except for our custom forms.’ I tried it and he’s absolutely correct. I loaded up his forms and ones that Technical Specialist Bob – K8MD created. When selecting these custom forms in Flmsg, the application hangs. The included forms work fine. I tried to first debug and later re-work the process to no avail. If anyone has custom forms working on the Raspberry Pi, please contact me. The build instructions and additional notes about the issue are available: http://www.k8jtk.org/2015/10/13/running-fldigi-flmsg-and-flwrap-on-the-raspberry-pi-2/

Speaking of Bob – K8MD, he wrote in to inform me that he’s been assisting with NBEMS during drills in Medina County. NBEMS (Narrow Band Emergency Messaging System (or Software)) is a set of standards for passing text based messages and files over ham radio. His proficiency and use of NBEMS was noticed by ARES folks in nearby counties. Bob reported on the event:

———-

On Saturday 5 December, Medina County ARES conducted a damage assessment drill with Medina County CERT team. The exercise was centered around the Damage Assessment form that I created for FLdigi. The objective of the exercise was to complete an initial damage assessment of an area that had been hit by a tornado. This initial damage assessment must be completed by the County EMA within 12 hours. This initial damage assessment is used by FEMA, the Red Cross, and other agencies to increase their situational awareness. The information is used to determine the size of the response necessary for the incident.

The exercise was a resounding success! CERT was divided up into six teams. Each of these teams had a mobile / portable ARES station paired up with the team. The CERT volunteers filled out the damage assessment forms and the ARES stations transmitted the forms back to the County EMA. The amount of information passed in a short amount of time was quite impressive.

One of the key things that I think we learned at this exercise was to keep the digital traffic on a separate frequency and separate band from the FM phone net. The traditional FM phone net was established on a 70cm repeater. A two meter simplex frequency was designated for the digital traffic. The portable ARES stations would use the FM phone net to ask permission to send digital traffic on the digital channel. This permitted the normal FM phone net to resume operations while the computers did all the work transferring the digital traffic on a separate channel. It’s critical that the digital channel take place on a different band then the FM phone net, so that the digital traffic receive is not de-sensed from adjacent frequency intermod. It’s also important for the stations doing a digital transmission on an FM phone frequency to announce: “CALLSIGN with tones” before transmitting. One of the digital transmissions went over a repeater and a non-ARES ham that was listening, thought the repeater was malfunctioning and allowing paging signals to be re-transmitted.

Mike Brugger, N8CEY is the ARES EC for Wayne County. He came up to observe the exercise from the Medina County EMA. I helped him get FLdigi and FLmsg installed and properly configured on his laptop, while he helped me with Net Control duties. Mike left with an extremely positive appreciation for the digital traffic handling. He’s planning to take the knowledge back to the Wayne County ARES team and start training on FLdigi.

———-

Thanks for that great report. Bob, Dave – NF8O, Fred – K8FH, and I put together a hands-on NBEMS training session for Medina county. The sides are available online: http://www.k8jtk.org/2015/11/10/vhfuhf-nbems-an-introduction-using-fldigi-and-flmsg-presentations/

Thanks for reading and 73… de Jeff – K8JTK

Amateur Radio, ARRL Ohio Section, Ohio Section Journal

Ohio Section Journal – The Technical Coordinator – December 2015 edition

December 17, 2015 Jeffrey Kopcak

Once my article is published in the Journal, I will also make it available on my site with a link to the published edition.

Now without further ado…

Read the full edition at: http://n8sy2.blogspot.com/2015/12/december-issue-of-ohio-section-journal.html

THE TECHNICAL COORDINATOR
Jeff Kopcak – TC
k8jtk@arrl.net

Hey Gang,

By now you have all the decorations up on the tree and house, Christmas cards mailed out, shopping done, right? Anyone? Yeah, me either.

One device you might want to put on your Christmas list for Santa is the YARD Stick One (Yet Another Radio Dongle). It’s a dongle to transmit and receive signals below 1 GHz, which include the 440 and 900 ham and ISM (industrial, scientific and medical) bands. This device was created by ‘hacker turned Ham Radio operator’ Mike Ossmann – AD0NR. He’s the founder of Great Scott Gadgets (http://greatscottgadgets.com/) which makes gadgets like the HackRF One or Ubertooth One.

The YARD Stick One is a half-duplex transmit and receive dongle that operates (officially) in the ranges of: 300-348 MHz, 391-464 MHz, and 782-928 MHz. Unofficially: 281-361 MHz, 378-481 MHz, and 749-962 MHz. Modulations schemes: ASK, OOK, GFSK, 2-FSK, 4-FSK, MSK. HAK5 did a getting started video: https://www.youtube.com/watch?v=pkTlTCUeec0. If you get one of these devices, let me know what you do with it! More: https://greatscottgadgets.com/yardstickone/.

If you’re more a Raspberry Pi person, the foundation released the $5 Raspberry Pi Zero. It features a processor about 40% faster than the Raspberry Pi A with 512MB RAM, micro-SD card slot, mini-HDMI socket, Micro-USB for data and power, unpopulated 40-pin GPIO header identical pinout to Model A+/B+/2, unpopulated composite video header, and a form factor of 65mm x 30mm x 5mm. More: https://www.raspberrypi.org/blog/raspberry-pi-zero/

The Fo Time podcast had an episode that I found very interesting. Fo Time is actually a Ham Radio podcast. Their subtitle is ‘the Other Ham Radio Podcast.’ Episode 38 is titled “Ham Radio-Listening to the Spectrum.” As someone who loves to operate on the ham bands I’m very interested to scan around from time-to-time to see what else I can hear. The episode goes though the allocations and uses of radio spectrum. It is an overview but they will talk about radios to receive frequencies and modulation types. Give the episode a listen. I found it interesting and learned a couple things. At the end, they encourage you to get out there and tune a block of frequencies. You’ll be shocked to learn what is going around you that you had no idea. More: http://amateurradio15.com/38/

I plan to do a rundown of Ham Radio podcasts I’ve found in a future edition of the OSJ. There are many out there and your fellow hams are putting a lot of effort to bring you ham radio related topics — for free.

I had a great time at the NOARS meeting this past November. I presented my program on the Raspberry Pi. It sparked a lot of great questions, discussion, and even correspondence after the meeting about possible uses for the device. Thanks for having me at your meeting.

Welcome to Tracey W8TWL as the latest addition to the Technical Specialists. He brings a lot of commercial experience to the group. He has a GROL (General Radiotelephone Operator License) which allows him to repair aviation, marine, and fixed stations. He is a certified member of the SBE (Society of Broadcast Engineers), and helped track down false emergency calls, pirate radio stations, and RFI problems. I’ve been to a couple SBE meetings. Want to know what it takes to keep an AM/FM/TV station on the air? These guys have all kinds of war stories!

Thanks for reading. Happy holidays, Merry Christmas, and Happy New Year!

73… de Jeff – K8JTK

Jeffrey Kopcak, MBA – K8JTK

Calibrate Receive Audio for Ham Radio Soundcard Digital Modes

Program versions

Download and Installation

Configuration

Setting receive level audio

Examples

Ohio Section Journal – The Technical Coordinator – April 2016 edition

SSTV Transmissions from the International Space Station – April 2016 edition

Ohio Section Journal – The Technical Coordinator – March 2016 edition

Bridge a Remote Site Network with OpenVPN Access Server

Security

Choose a good router

Virtual Private Network

Hosting

IP addressing

Downsides

Assumptions

Program versions

Ohio Section Journal – The Technical Coordinator – February 2016 edition

About the ARRL Ohio Section Technical Coordinator presentations

Framework

Navigation

Links

Presentations

Slides

Version 3

Version 2

Version 1

Digital Communications in Amateur Radio: Overview

Ohio Section Journal – The Technical Coordinator – January 2016 edition

Ohio Section Journal – The Technical Coordinator – December 2015 edition

Ham radio and tech.