G5RV vs Loop noise

G5RV on left, Loop on right, as seen in the Audacity audio editing program from Skype audio connected to W4UOA's transceiver. The recording was made at 9:10 am CST, when 75 m was no longer ideal for the 430-mile path between me and Carl.

Below are partial screen captures from the audio recording at three selected time segments.

WA5MLF audio as heard at W4UOA with the new loop antenna selected. Click here for the MP3 audio recording.

W4UOA speaking and then switching from loop to G5RV antenna. Click here for the MP3 audio recording.

Switching back to the loop antenna after not hearing WA5MLF in the noise heard on the G5RV antenna. Click here for the MP3 audio recording.

Tuesday night squall line

Here are two screen shots I saved as the front with squall line arrived in Baton Rouge.

Click above to enlarge.

 2-hour lightning history from LightningMaps.org, as of 2248 CST. 

Click above to enlarge.

Weather radar from Weather Underground Wundermap, as of 2254 CST. The red place marker is Baton Rouge.

Test posting via email

Here is a posting sent via email.
Shown below is a photo of disassembled left-click switch in a mouse.

Splatter on 7191 kHz

This morning, during the RV Service Net on 7191 kHz a strong (S9+20) station on 7195 kHz generated some audible splatter on the net audio as heard at my location. Below are two different displays I captured from my Flex-3000, showing the energy that was received below 7192 and above 7195.

Click above to enlarge.

 The above image is the panascope display with the 5 kHz receiver bandwidth setting. I added a green horizontal line for reference to the noise floor on vacant frequencies below 7189. I set the receiver to display the peak received signal at each frequency sample.

Click above to enlarge.

This image is a capture of the waterfall display. The elapsed time from top to bottom is 30 seconds, for the window size (not full screen) that I was using. Splatter from the 7195 station is clearly visible above 7195 and below 7192.

Range circles from WA5MLF

This map shows circles of distance from my location, in increments of 100 miles.

Click on map for expanded view.

Windows 10 installing without permission

Click to enlarge

I found many references to this issue, reported by folks who are fighting the same upgrade demon.  The screen shot here shows the history of failed upgrades on one of the Windows 7 office computers that I support. This behavior has sometimes bogged down the computer's performance, hampering the user's productivity.






Below are a few of the links with answers that seem to have the following elements in common:

• Uninstall updates KB3035583, KB2990214, and KB2952664
• If KB3035583 comes back, uninstall it again, then in the updates available for download and install, right-click on it and select Hide update.If that does not work, see the 3rd link below.
• Turn off automatic updates to prevent these from installing again. There is an "Optional" update 'Upgrade to Windows 10 Pro' which IS automatically selected. You'll need to manually select future critical / important updates for installation.

Stop Windows 10 upgrade


Windows 10 upgrading without permission


Removing the get Windows 10 icon


Uninstalling a Windows update


Windows 10 may already be on your PC even if you don’t want it

Recursive VoIP Phone Patch

This morning W4BXI was testing his VoIP phone patch arrangements using a Google Hangout. As the radio propagation gradually faded on 3740 kHz to my location, due to rising sun, he added me to the patch on my cell phone. Later he added W4UOA via his cell phone. Carl wondered if there was a way for us to test the use of a separate Google Hangout between the two of us and bridge it to the Hangout that John originally established. By calling his cell phone from the second Hangout, Carl was then able to bridge the two voice calls on his phone and enable us to talk and listen via our PCs while patched to the W4BXI station.
The sketch here shows the arrangement, with separate colors and line styles to distinguish the components. (Click on it for a full size view.) This "lash-up" worked very well for us! It is not intended for routine use, of course.

Naturally, the first choice for patching with a Google Hangout is to connect the person via his or her Google ID on the Hangout, for best audio quality (and video). A connection to a cell phone or landline phone is the second choice.

Update:  A new web app for Hangouts is now available.
Just point your browser to: https://hangouts.google.com

Windows 10 Issues & Tips

Now that Windows 10 is officially available, various privacy issues are being discussed, along with numerous tips for upgrading from Windows 7 & 8. Here are some selected articles that may be of interest to those who are upgrading to Windows 10 or purchasing new computers with it pre-installed:

• Should You Upgrade?  (from the Houston Chronicle Tech Blog)
• Review  (from TechRepublic)
• Privacy and Data Sharing  (from TechRepublic)
• Using Your Bandwidth  (from the Houston Chronicle Tech Blog)
• Windows 10 Tips  (multiple articles from Paul Thurrott)
• Privacy Tradeoffs (see pages 3-6 of these show notes)

Update 8/21/2015:  Also see:

• Complete Guide to Windows 10 
• Understand and Configure Privacy Settings

VirtualBox and Windows 10

A recent posting on Google+ reported the availability of VirtualBox 5.0.  This page describes how to install it on three related "flavors" of Linux, so I decided to take it for a spin to see how it handles a preview version of Windows 10. Below is a screen shot that shows Windows 10 running on the virtual machine on my Ubuntu 14.04 Linux desktop.

Click above for larger view.

I was testing the performance with the live video stream of this week's Security Now netcast and opened the Windows 10 "menu" for display on the left side of the window. The Linux desktop has the same elements that I described in my earlier post that made use of the Kernel-based Virtual Machine.

For the VirtualBox virtual machine I allocated more CPU, memory and disk space than before, and the video performance seemed to improve accordingly. This virtual machine was also able to produce the audio generated by Windows 10. My previous work with the Kernel-based Virtual Machine did not produce audio, but there is probably a setting I needed to change to make it work.

The two virtual machines that I used require about the same level of effort to configure.

TWIT.TV Shows

Below is a list of the TWIT.TV shows that I like to see or hear on a regular basis. I don't get to all of them every week. Most often I download the audio or video recording and play it using VLC. This makes it easy to jump ahead or rewind or pause and resume. It can also speed up the playback.

I also use the TWIT Pro Android app on my phone to access the shows, either live or downloaded, when I am moving around (e.g. doing yard work). TWIT apps are available for iOS and Windows Phone, also.

This complete list of shows has links to the latest episode of each, where you can stream or download and save the recordings.

The shows I consume or browse, in approximate decreasing order of frequency or priority, are:

• Security Now
• Ham Nation (video recommended)
• Windows Weekly
• This Week in Enterprise Tech (video recommended)
• Tech News Today
• Know How (video recommended)
• This Week In Tech

The topic summary for a given episode helps me to choose an episode for viewing or listening. In some cases the show notes / links provide enough content.  

I've browsed a few other shows sporadically.

Lightning Maps

During this morning's QSO I disconnected the antenna feed twice due to nearby lightning. I looked at various lightning data web sites I had bookmarked and found one that let me pan and zoom to the degree I wanted. Below are two screen shots from LightningMaps.org that uses data from Blitzortung.org to overlay a Google map. When I selected Real Time near the upper left corner on the initial map I found I was able zoom in and pan. I also could select the amount of history to display, using check-boxes across the top of the map.

First is the view captured at 0722 CDT, 3/10/2015, with 2 hours of data. 

Click above to enlarge view.

Next is the view from 0930 CDT and shows 24 hours worth of data, using more colors.

Click above to enlarge view.

I intend to keep this site handy for future reference.

Sudden radio black-out on low bands

click above to enlarge view

Yesterday morning during the 3740 kHz QSO with W4UOA, N4NR and K4JPM, we noticed a sudden, extreme drop in signal level on 75 m. We switched to 60 m. Carl and I could not hear each other, and Dennis could barely hear us. We were keeping in touch on the chat room. A brief visit to 40 m had similar results. We suspected a sudden solar event, and Dennis pulled up the graph shown above and shared the link with us via the chat room. The time stamp on the page bottom was just after we noticed the big signal drop. Dennis later added the red arrows pointing to the big spike.
He reported later spikes in an update to his Facebook post and included this link to the flare photos published by NASA.

The current X-ray Flux graphs are available here.

Two online malware scanners

A recent issue of PC World magazine suggested two free online malware scanners as a supplementary check of your Windows PC that may already have installed anti-malware software, or if you are having current malware symptoms:
Free Online Virus Scan - Antivirus Software - Trend Micro USA
Free Virus Scan | Online Virus Scanner from ESET 
I mentioned these to the Monday morning radio group, and used them later on my two desktop PCs that currently have the Avast Free AV installed.


On my office PC, 2006 vintage with two drives, I first rain the ESET online scanner. It ran for 2 hours and appears to check all files. It found several instances of potentially unwanted applications  (listed below) and deleted/quarantined them. Drive C is the newer Win 7 drive; Drive F is the older Win XP drive, which I almost never boot up now. I did a Google search on the reported Win32/InstallCore.QW and found the tally at virustotal.com to be very interesting:
https://www.virustotal.com/en/file/2ca33500c1e3c129aad55a092717a9044cd0e1919e24ce78211ebd4611572826/analysis/

Next I ran the Trend Micro Housecall and it found nothing. It took only a few minutes to run and I'm not sure if it also checks for potentially unwanted applications in additional to the truly malicious stuff.

On the ham shack PC, 2013 vintage with two drives, the Trend Micro Housecall scan found nothing. Then I ran the ESET scan, with the option again set to include potentially unwanted applications in its search. It took just over an hour to scan the two drives (315,385 files). On the older drive F, that was originally in the office PC years ago, it found two potentially unwanted applications. The program automatically quarantined them and gave me the option to delete them upon completion of the scan.

I concluded that both online scanners are worth running if you have current malware symptoms or just want to occasionally supplement your normal resident anti-malware software.  As malware developers and users have become more sophisticated and sneaky with their methods, it is more important than ever to not rely on any single protection method and to be even more vigilant about emails and web links.

==================================================================
Results of ESET scan on 2006 vintage PC.  User names replaced with ****.

C:\Users\****\AppData\Local\Temp\ICReinstall_Evernote_5.7.1.5586_inst.exe   

a variant of Win32/InstallCore.QW potentially unwanted application    deleted - quarantined

F:\Documents and Settings\All Users.WINDOWS\Application Data\InstallMate\{16782E9C-E344-47BD-

A045-B9BA79870632}\_Setupx.dll   
a variant of Win32/InstalleRex.U potentially unwanted application    deleted - quarantined

F:\Documents and Settings\****\My Documents\Downloads\aoeprzip.exe   
a variant of Win32/OpenInstall potentially unwanted application    deleted - quarantined

F:\Documents and Settings\****\My Documents\Downloads\outlookexpress-setup(1).exe   
Win32/DownloadAdmin.G potentially unwanted application    deleted - quarantined

F:\Documents and Settings\****\My Documents\Downloads\setup-bluegriffon.exe   
Win32/DownWare.W potentially unwanted application    deleted - quarantined

TPWINLOG 2015 in Windows 10

Click above for large view

TPWINLOG 2015 installed flawlessly in the Windows 10 Technical Preview that I have running in a virtual machine hosted by Ubuntu 14.04 Linux. This screen shot shows the program window displaying some practice contacts I entered for test purposes. I also verified that the Print ToFile feature produces the desired text file.

I don't know yet if I can test the CW send feature with this arrangement.

Supplies for Crawfish Boil

Here is one example of a local grocery store floor display of supplies for a crawfish boil. Included are: 80 quart pot, packages of crab boil and crawfish boil spices, round plastic trays (in Mardi Gras colors), and cases of canned beer.

Windows 10 Preview on Linux Virtual Machine

Click above for a larger view.

Here is a screen shot of the Windows 10 Technical Preview running as a guest OS in a virtual machine in Ubuntu 14.04. Windows 10 is in the smaller window (1024 x 768) in the center of the wide screen (1920 x 1080) Linux display. It can also be run in full screen mode.

The Kernel-based Virtual Machine is configured to use one CPU core, 2 GB RAM and 12 GB disk space.  The Windows 10 setup asked for 11.1 GB of disk space. After install there was 2.64 GB of free disk space. A bunch of apps were downloaded and installed automatically after the basic Windows 10 installation completed.


At the far left of the Linux screen is the standard Ubuntu Unity launcher (dock). At the far right is the Conky Seamod widget that shows various aspects of resource usage on the host PC.

My reference for setting up the virtual machine was this article. Performance of Windows 10 is quite good under this configuration, and gives a good opportunity to try out the preview version.

Password Management

Below are my notes about several methods and tools for password management. Individual needs and preferences will always help to determine the best approach. 

For a collection of articles that review various password management programs, scroll down to the section labeled  "Reviews".

Paper Records

• easy to use, but requires manual keyboard entry of login data
• storage is offline
• must be stored and transported securely
• may not be with you when you need it
• no electrical power needed to access
• frequent updates can get messy

Web Browser Password Storage

• built into popular web browsers
• convenient for most web sites
• storage by web browser on your device is not highly secure
• password data can be lost if not backed up
• must synchronize among multiple devices
• master password strongly recommended for user access

Spreadsheet Password Storage

• convenient for most web sites
• storage by spreadsheet file on your device is not highly secure
• password data can be lost if not backed up
• must synchronize among multiple devices
• master password strongly recommended for user access

Cloud-based Password Managers

• encrypted password data is shared among all of your registered devices via cloud storage
• all encryption / decryption is done on your device
• software must be installed on each device
• can augment security with a hardware multifactor authentication device
• able to capture login information during initial login creation on a web page
• automatically enters login information on subsequent logins
• easy to create new login information and updated passwords
• can generate strong random passwords that meet web site requirements
• can securely store content other than logins
• a master password is required

Local Computer-based Password Managers

• encrypted password data is stored on your device (computer, phone, flash drive / removable media)
• data file must be backed up
• if removable media used for storage, must transport between devices
• all encryption / decryption is done on your device
• software must be installed on each device
• some can augment security with a hardware multifactor authentication device
• data can be shared among all of your devices via manual copy process, local server or cloud
• easy to create new login information and updated passwords
• can use copy / paste or auto-text to apply login data to a web page
• can generate strong random passwords that meet web site requirements
• can securely store content other than logins
• a master password is required

Reviews

Many articles are published that review and compare password manager programs. Here are a few for information. The first article does a very good job of explaining the big picture and the specifics of various approaches.

Password managers: Are they safe? Which is the best?
The Best Password Managers
Lifehacker Faceoff: The Best Password Managers, Compared 

Take control of password chaos with these six password managers

Web Browser Based Password Managers  -- See page 5

Top 10 password managers

80 m Dipole Bandwidth

Some recent conversation in our morning group touched upon the bandwidth of an 80 m dipole. We know that the commonly used wire diameters do not allow low-SWR coverage of the entire 500 kHz of bandwidth. Here are model results showing the bandwidth of a theoretical dipole that is fed with a 73-ohm source.

126 ft dipole; no feedline

 This first figure shows the SWR vs frequency for a 126 ft dipole at 50 ft above ground. The source (transmitter) is connected directly to the center of the dipole. Choosing the data points close to the SWR=2 line gives a bandwidth of about 230 kHz (marked in green). At SWR=3 the bandwidth is about 380 kHz (marked in orange).

The next figure is for the same dipole with a feedline having 73-ohm characteristic impedance and fed with a 73-ohm source.

125 ft dipole; 73 ft feedline

The bandwidth for this case at SWR=3 is about 360 kHz -- slightly less that the first case. Additional data points would be needed to more precisely locate the frequencies where SWR exactly equals 3.

An additional model case for feedline of 70.3 ft yielded very close to the same results as for 73 ft. There is little effect from changing the feedline length when operating with feedline characteristic impedance and source impedance close to the impedance of the dipole near resonance.

UPDATE:  I changed the feedline and source (transmitter) impedance to 50 ohms, leaving the other parameters unchanged. The model gave:

• SWR less than 3: bandwidth 280 kHz
• SWR less than 2: bandwidth 150 kHz
• minimum SWR = 1.37

For the cases of 300-ohm or 450-ohm feedline, the SWR is greater than 3 across the entire range of 3.5 to 4.0 MHz, requiring the use of an antenna tuner or other impedance matching methods to operate with a 50-ohm transmitter.


A dipole that is longer or shorter than 1/2 electrical wavelength at the operating frequency will have considerably different SWR than the above ideal cases. Likewise, using a feedline that is much different than the dipole's resonant impedance will affect the SWR significantly. Under these conditions a different definition of bandwidth is needed and relates more to the impedance range that an antenna tuner can accommodate, since the antenna will present a much higher SWR on its own.

WA5MLF

Static Crashes on 3740

Here is an annotated screen shot of the waterfall display showing the static crashes as pale or brighter horizontal strips. The time scale is about 47 seconds from top to bottom.