Antenna party at Zamora

Here is a set of photos from the antenna party organized by KE4ID at the Zamora Temple site used during Field Day in recent years. The objective was to compare the performance of several antennas in advance of Field Day. Click on the slide show thumbnail if you wish to view individual photos in the web album.

BirmingHAMfest Group Photo

A photo of our group's gathering at the 2011 BirmingHAMfest joins the many that appear on the Group Photos page linked to our home page.

When you arrive at that page you'll also see reference to W4AXO's presentation. A link to his new logging program is included there and also on the Telephone Pioneer QSO Party page that is linked to our home page.

Java update breaks chat room copy/paste

UPDATE: See comments at bottom of this posting for a solution that works for all versions of Java.

Regular users of the Bell Ringers chat room know that it requires Java to be loaded by the web browser so the addonChat applet can run. Recently I accepted the latest update -- Java 6 Update 24. I considered this worthwhile since the update patched multiple vulnerabilities.

On the next morning I noticed that I could not paste a web link or any other text into my outgoing chat message bar. If you never have the urge to paste a URL or other text into your message bar, you can ignore the rest of this post.

Pasting URLs, etc. has become a popular way of sharing diverse discussion topics and sources of additional information during our morning QSOs. I soon suspected the Java update as a trigger for the trouble. Through the addonChat support page I submitted the issue and got a speedy response. I assume that the paying business customers of addonChat brought up the issue right away. Here is an excerpt from their reply:

We've just recently been made aware of apparent bugs in the latest build of Java 1.6. This security release appears to have unintentionally disabled both copy and paste using CTRL/CMD commands as well as hot-linking to remote images using the IMG tag.

We're currently awaiting further information from Oracle regarding this and hope their next build resolves these issues.

In the meantime, we recommend uninstalling Java from your system and downgrading to Java 1.6.0_23 (Java 1.6 build 23). You may download a copy from http://www.oldapps.com/java.php

Below you will find the steps to uninstall Java update 24 and reinstall Java update 23. Java defaults to notify (or update) you automatically, so you will want to disable this action until we determine that a subsequent Java update resolves this issue.

For Windows XP:

• First, use Control Panel, Add or Remove Programs and remove Java 6 Update 24
• Go to: http://www.oldapps.com/java.php and download Java 6 Update 23
• Install Java 6 Update 23
  
• Disable updates:
• Go to Control Panel, open Java Control Panel
• On the Update tab, Un-check the Check for Updates box
• On the Warning page that pops up, choose never

For Windows 7:

• First, use Control Panel, Programs and Features and remove Java 6 Update 24
• Go to: http://www.oldapps.com/java.php and download Java 6 Update 23
• Install Java 6 Update 23 (I chose the x64 version for my Win 7 laptop)
  
• Disable updates:
• Go to Control Panel, open Java Control Panel
• On Advanced tab, expand JRE Auto-Download
• Check Never Auto-Download
• Click OK

If, during the Java update 23 installation you get an offer to add the Yahoo! toolbar, I suggest that you decline it (un-check box), unless you really want it. 

That should cover it. When I get word of Java 6 Update 25, I'll test it for chat copy & paste and advise.

(This blog entry updated 4/6/11)

75 m Voice & Video Party

This morning we had quite a crowd on 3740 LSB and occasional CW. We also tried out Carl's expanded Adobe Acrobat.com account with ConnectNow web conferencing.

Carl shared his desktop, showing TRX-Manager software, with a multitude of our participant log-ins and web cams. Below is one of the screen shots I captured during the peak of activity. Click on the thumbnail below for a full size image.

Recently we've used the desktop sharing feature to share live demonstrations of SDR software (by KE4ID) and antenna modeling software (by WA5MLF). Carl has used the desktop sharing on numerous occasions to demonstrate TRX-Manager, Ham Radio Deluxe, and Master Commander software for local and remote control of ham radio systems.

ConnectNow is a powerful and fun tool for sharing knowledge among members of the group.

Antenna radiation patterns - 220 ft dipole

Here are some radiation patterns for this antenna for 160 thru 10 m bands, using 40 ft height above rocky ground. No feedline was used for this analysis; the source was located at the mid-point of the antenna.

Each slide identifies the frequency and orientation (vertical plane or horizontal plane). The maximum gain (red line) and -3 dB gain points (green lines) are marked. A short horizontal red line near the center of most plots represents the antenna structure, oriented broadside to the viewer. For 40 - 10 m, 3D color plots are also included. A white line in those plots represents the antenna structure. x, y and z axes (barely showing) are in green.

Click on the image below to access the slide set where you can play a slide show or view individual slides.

Dipole, 220 ft, 160 - 10 m

Bell Ringers on Skype Video

Here are two views that I captured during yesterday's Skype video conference, which included a walking tour of Dave's new QTH. Click on each image to see the full-size copy.

The image below shows a close-up of the SoftRock SDR transceiver that Jack is now building.

Happy New Year 2011 to all!

Frequency Analysis of On-Air Audio Recordings

I used the FFT frequency analysis feature in my audio editing software to produce some views of audio from several members' transmissions as received on my Heathkit SB-104A. The results are presented in this photo album. Click on the first thumbnail image to display it full size with its caption. You can use the two arrowheads above the image to go backward and forward to compare images. Or you can select the slide show mode and navigate using controls below the photo. All graphs were made with the same settings in the audio software. Two overlay images show a pair of curves on a single slide.

Here are some additional notes:

• All audio recordings are influenced by the receive passband and audio filtering of my SB-104A 
• A local peak appears around 3 kHz in all graphs. This is a birdie in my receiver and should be ignored.
• Each horizontal line represents a 3 dB amplitude step -- a factor of 2 power ratio
• Each graph is the result of FFT analysis of the speech sample that was recorded, and the frequency content varies according to what slice of time you choose to analyze. Speech is a complex, continuously changing waveform. Pure, steady tones would give more consistent results.
• My software can present a real-time FFT of the audio as it plays. In that case the frequency display varies continuously as expected for a complex, continuously changing waveform.
• Increasing the FFT size from the 1024 used in these graphs to higher numbers (2048, 4096, etc.) reveals increasingly fine details, but does not affect the overall shape of the response shown in the lowest (1024) setting. 

John