Monday, 27 July 2015

Words of Wisdom from the Past

...about transmission lines. This article, by an unknown author but edited by Doug VE3CWO (Now VE3VS) provides some pointers on understanding transmission lines. It has been scanned from the January 1974 edition of the Splatter and passed through optical character recognition for publication here. You can see the entire newsletter scanned from an original on the YRARC web site. Thanks to Bob VE3WY and Rob VE3RQB for passing this along.


While the following statements are elementary to many old-time amateurs, it is hoped that these condensed and simplified points will be of some help to the newcomer in obtaining better performance from his station.

  1. To deliver maximum power with lowest losses, a transmission line must be terminated in a resistance equal to the characteristic impedance of the line.
  2. A correctly terminated transmission line of any length will, from the sending end (transmitter), appear as an impedance equal to the characteristic impedance of the line.
  3. A correctly terminated and balanced line has essentially no radiation from the line.
  4. A correctly terminated line has the most power absorbed by its termination (load); hence, none is reflected and its V.S.W.R. is unity.
  5. If a line must be pruned or adjusted to a critical length, it is not terminated properly.
  6. No matching device at the sending end (transmitter) can reduce the V.S.W.R. on a line which is improperly terminated.
  7. An improperly terminated or unbalanced transmission line will:
    1. Reduce power capacity of T.V.I. filters.
    2. Distort radiation and polarization patterns of the antenna.
    3. Induce power losses in nearby objects or buildings.
    4. Increase B.C.I. and T.V.I. problems.
    5. Not absorb or transfer maximum power from many types of transmitters.
  8. Improperly terminated transmitter lines, when used for receiving, may cause reduction in apparent receiver sensitivity due to losses because of mismatch between antenna and line.
  9. To obtain maximum transfer of power between any two networks, the impedances must be equal, or must be equalized by a matching network or transformer.

Thursday, 23 July 2015

The Splatter now has a Propagation Forecast

... and it's not very good - at least not right now. Fair conditions day and night on 20 and 30m (where I'm running right now, so far working England and Texas), fair on 40/80 at night, and poor for everything else.

Anyway I thought I'd add it to the sidebar on the right immediately below the blogroll. I hope someone finds it useful. Let me know if you like it (or otherwise).


P.S. It doesn't seem to show up in the mobile version of the site.

Monday, 20 July 2015

YRARC Board Minutes - June 16, 2015

Meeting held in the Magna Centre. Called to order at 19:06. Chaired by Chris VE3NRT. Board members attending; Chris VE3NRT, Rob VE3RQB, Chris VA3DXZ, Steve VE3UT, David VA3DCY, John VA3JI, Geoff VA3GS. Board members absent: Barry VA3LLT, Eric VE3EB. New board members attending (terms beginning July 1, 2015); Alf VA3BLE, Doug VE3ATP
  1. Motion 2015-06-16-01 by John VA3JI to adopt agenda, seconded by Geoff VA3GS. Motion carried.
  2. Motion 2015-06-16-02 by Geoff VA3GS to adopt May 19, 2015 board meeting minutes as published in the splatter blog at, seconded by Steve VE3UT. Motion carried.
  3. New board member orientation (Chris VE3NRT)
  4. Governance
    • Treasurer’s report (John VA3JI)
        Balance at May 31 2015 [Available to members by request to Secretary]
      • Income $50.00
      • Expenditures $553.31
      • Balance as of Jun 16, 2015 [Available to members by request to Secretary]
      • Motion 2015-06-16-03 by John VA3JI to accept the treasurer’s report, seconded by Geoff VA3GS. Motion carried.
  5. Property (Rob VE3RQB)
    • The communications trailer was deployed to the Aurora Street Sale. The generator was found to be low on fuel.
    • Rob VE3RQB requested that the communications trailer generator fuel tank be topped up prior to return to the Bales Road site for storage.
    • Rob will advise those persons authorized to tow the trailer, of this new requirement.
    • Motion 2015-06-16-04 by Rob VE3RQB that Carlos VA3CAZ be added to the list of authorized towers for the communications trailer, seconded by Geoff VA3GS. Motion carried.
    • Chris VE3NRT will create an email distribution list for the authorized towers, update the Trailer Policy and distribute it to the authorized towers list.
    • Motion 2015-06-16-05 by Rob VE3RQB that the club allocates $90.00 for the purchase of 3 parking pad’s which would be used to anchor the tower trailer guys when deployed on pavement or other hard surfaces, seconded by Geoff VA3GS. Motion carried.
  6. Repeaters (Steve VE3UT)
    • 6m diplexer is now tuned to Tx 53.49 MHz with -1 MHz offset for Rx 52.49 MHz with 110dB isolation. There is no PL tone.
    • Level of the link radio in Aurora was adjusted
    • Reconfiguration of batteries at VE3YRC-VHF site
      • The DC power supply feeding the batteries was found to be introducing noise.
      • The batteries were isolated so that one battery now feeds the link radio and the remaining battery feeds the VE3YRC-VHF repeater. The power supply DC continues to feed the VE3YRC-VHF repeater battery and a trickle charger was installed and connected to the link radio battery.
      • As a result of these changes, the battery backup time for the VE3YRC-VHF repeater is reduced.
      • Steve reported that a total of $199.79 has been spent against the $200.00 repeater float.
      • Motion 2015-06-16-06 by Geoff VA3GS to increase the repeater float (Motion 2015-03-17-06) from $200.00 to $300.00 to accommodate the purchase of a trickle charger for the link radio battery, seconded by David VA3DCY. Motion carried.
  7. Events – No report
  8. Emcomm
    • Chris VE3NRT reported that the May 29th York Region 'Back 2 Basic' exercise went well and drew attention to Robert VE3BXG’s report emailed earlier to the board (see attached)
    • Steve VE3UT discovered the Thornhill Amateur Radio Club’s 2m antenna discarded on the roof of the MacKenzie Health Centre. Steve suggested we request direction from Emcomm on what to do with the antenna.
  9. Membership
    • Field Day: Motion 2015-06-16-07 by Steve VE3UT that the club allocates $253.12 for the rental of toilets for field day, seconded by Geoff VA3GS. Motion carried.
    • Guest speakers;
      • Sept 2015 Rocketry / AM Radio
      • Oct 2015 - Dr. Delaney
      • Nov 2015 – Barry VE3ISX remote stations
      • Need suggestions for remaining meetings
  10. Trillium Goals: Chris VE3NRT reported that at the last Emcomm meeting, they discussed the next phase of infrastructure that the club should consider for a future Trillium grant.
  11. Other business
    • John VA3JI requested that the job of property valuation be handled by the property manager going forward
    • John VA3JI reported that the IRLP is unstable with the TX locking on after a power reset. He is looking into options to replace it or repair it.
    • Geoff VA3GS responded to a question from Steve VE3UT confirming that he had not yet received a response from WYNSORC.
    • Doug VE3ATP confirmed he will tow the tower trailer to the field day site next Tuesday
  12. Meeting adjourned

Sunday, 12 July 2015

Field Day 2015 - a wet one

For the past several years, the weather on Field Day weekend has been magnificent. That streak of luck had to come to and end at some point and much of the North East experienced cool, rainy and windy conditions for almost the entire 24 hours of operation.

Luckily we were spared during set up and most of tear down, and just before 2pm we were ready for the pep talk from Steve VE3UT and a team photo while it was still dry.

Not long into operations, the rains came. By evening it was heavy at times and wind started to pick up. Fortunately our antenna tower was well secured with 3 guy ropes and showed no signs of movement. While it didn't have any beams attached it did have 2 flags that were extended straight out in the wind despite being soaking wet.

At about 1:30 am there was some visible lightning and most stations decided to shut down. I took the opportunity to go home and get some sleep, although I'm sure that cost a few points as 40m would be open to somewhere throughout the night. On 40m we had to use the tuner after a while to get the VWSR in check as it was changing with the conditions.

When I returned to the site it looked a bit worse for wear. One of our signs was lying flat on the shoulder of Van Dorf Sideroad while the other looked like it had taken a beating.

By morning the grounds were waterlogged and muddy, and some of that water had found its way into the tents. Our tent had plenty, but fortunately the equipment was spared.

A good supply of napkins is useful under such conditions.

The weather started to break a bit by breakfast time but was still raining heavily off and on until we started to tear down the site after lunch. With plenty of shelter and rain gear we made the best of it.

Field Day is many things, including an emergency simulation exercise to practice communications without any outside support. Emergencies can happen in any weather conditions so we should feel grateful that we had the opportunity to practice our skills under less than ideal conditions.

Saturday, 11 July 2015

Eclipse on the Raspberry Pi 2

One of the things I picked up at Dayton this year was a Raspberry Pi 2. The Pi 2 features 4 USB ports (vs. 2 in the original), a faster, quad-core processor, a gigabyte of memory, more GPIO pins, and a micro SD card slot (vs. the standard SDHC card in the original). Composite video out has been dropped.

I wanted to test the Pi 2 as a development environment for Atmel AVR microprocessors as the PI 2 can directly program them using the GPIO port without needing a USB interface. That rationale is a bit weak but on the other hand I stand a good chance of learning something new as well.

So after acquiring and installing a version of the Raspbian operating system for the device, the next order of business was to install the Eclipse integrated development environment, the same one we used for Brad's (VE3HII) project night 2 years ago. This was pretty straightforward. Being used to the command line on Linux, I chose to install from there.

After making sure both the package database and system were up-to-date (using sudo apt-get update followed by sudo apt-get upgrade installing Eclipse is done with a single command: sudo apt-get install eclipse. That was easy and Eclipse installed and ran fine. However, it was missing the C/C++ tools, so the next step was to install those with sudo apt-get install eclipse-cdt. That's where things got tough. Eclipse would now crash shortly after launch and leave a log file behind which was little help in figuring out the problem.

Fortunately, we have an Internet at our service and several sources advised replacing the default Java JDK (Java Development Kit) with the one from Oracle. Eclipse is written in Java, by the way, so it executes within the Java run-time environment. A fairly terse description of the installation procedure can be found here.

There were some gotchas that had to be worked through.
  • Oracle has moved the ARM (the processor architecture found on the Raspberry Pi) version of to another web page. The web page referenced by the description has a link to new web page so that was relatively straightforward.
  • The directory /opt/jdk1.8.0/bin/javac mentioned is actually /opt/jdk1.8.0_33/bin/javac. This might change again in the future so the best thing would be to look in /opt and use whatever you find there.
  • The sudo update-alternatives --config javac will provide a list of several options for which JDK to run. The default will be not to change anything which isn't going to help you, so choose the one that looks like the Oracle SDK. If you get it wrong don't worry just run the command again and choose something else. The same goes for the sudo update-alternatives --config java command, of course.
After doing this, Eclipse will run fine. That's where I've made it to so far. There is still a long way to go, including installation of the tools to build AVR programs. I know from what I've read that this is possible to do on the Raspberry Pi so I will be trying that out soon.

Thursday, 9 July 2015

WSJT-X - Filling in the missing pieces

WSJT-X works as a standalone program and I used it that way for some time. Recently, as I mentioned in my last post, I enabled the connection to pskreporter so I could see whether similarly set up stations received my signal. Later versions of WSJT-X will even show your signal strength of the other station, which is an excellent way to determine band conditions, although sometimes it is frustrating when a station you want to work hears you but doesn't answer. However, as the system will run just fine unattended they may be just out of the shack rather than intentionally ignoring you.

WSJT-X keeps its own log in ADIF and text format which is fine for uploading, although you'd need to ensure that you're only uploading or importing the contacts logged since the previous upload. Also it records minimal information so if you want to record the US state for instance it lacks that capability, so I've typically entered JT65 contacts by hand into my logging program (DXLab/DXKeeper in my case) and suffered the consequences of various typos.

I'd heard about a program called JT-Alert but never found the time to try it until Canada Day, when I was cleaning up the shack and doing some research. The program was written by VK3AMA and is a free download for various versions of Windows. The advantage of JT-Alert is that it works with various logging programs to determine whether the call signs picked up by WSJT-X have been worked before on the same band and mode (WSJT-X will only tell you if you've worked the station before on any band or JT mode) and whether it's a new zone, country, state or grid (selectable by band so I only have grids set up on VHF, for instance). It even has a voice alert that will announce things like "New Grid" in your choice of male or female British voices, assuming you have a separate sound card from the one you use to connect to your radio.

The program supports standard ADIF files, DXLAB DXKeeper, HRD V5 or V6, Log4OM and MixW (CSV File), meaning it will work for just about everyone. It will also work with JT65-HF, which is an alternative implementation of the JT65 protocol with slightly different features.

So now the suite of software I run for JT65 and JT9 are as follows:
  • WSJT-X V1.5
  • JTAlertX 2.6.3
  • DXLab DXKeeper 13.0.6
  • Meinberg NTP (Network time protocol which is essential to keep your system clock in synch)
  • PSKreporter (although this is a service, not a program you download)
  • TrustedQSL which DXKeeper uses to upload and synchronize logs with ARRL Logbook of the World (LoTW)
After a week or so of operating I've discovered the following:
  • JT-Alert (at least with the settings I have currently) will advise me of new continents, zones, countries, grids (on 6m, as I've set it that way) and states for any station I've not worked before on that band and mode - whether they're calling CQ or not. In the 10 seconds available to decide what to to after seeing all the decodes come through, there's still some excitement in picking the best station to respond to that's actually calling CQ. The ideal way to do this is to look use the "decodes history" window but unfortunately you need to look at the right hand column to see whose calling CQ, then the left column to choose the best option to respond to, then find that station in the WSJT-X decode display, and then double click on it.
  • The programs should be started in a particular order. Meinberg NTP starts automatically on system startup, which is good because it can take 20 minutes or so to synchronize the system clock with network time. Then DXKeeper should be started. This is most important because otherwise JT-Alert will start it in the background. It will successfully look up stations that are heard in the DXKeeper log, but fail to actually log completed contacts. You will not be able to bring up the DXKeeper user interface either, as it will tell you that it's already running. Then JT-Alert can be started and it will prompt you to start WSJT-X.
  • There are several versions of JT-Alert that will be installed. You need to use the one that matches the JT65 program you are using. JT-Alert X is the one for WSJT-X.
  • It would be nice if I could somehow tell whether a "new country" was (a) never worked on any band (b) never worked on the band that I'm currently on (c) never worked on the mode (JT9 vs. JT65) that I'm currently using, or (d) whether it's just the band/mode combination that is new. I would give higher priority to stations earlier on the list.
  • In the end though, I will work anyone anywhere if I haven't worked them on that band/mode combination before. It's just that new countries, grids and states will be worked first.
  • In a week I haven't worked a single new country, although I've heard a couple (India and Indonesia) and worked some new band/country combinations on 30m and 17m.

JT-Alert is a way better method than what I was doing before, which was scrambling to look up stations I'd seen on the WSJT Band Activity window to see if I'd worked them on that band. This way is much more relaxing, but still has an element of decision making. I imagine someone, somewhere, is working on an add-on to run a fully automated station. That would be an interesting challenge to correctly respond to some of the non-standard messages that you see in this mode, and also to limit QRM with other stations on the band. Such a program would also ideally manipulate the power level of the transmitter to match the station being called. If see a station below -15db, for instance, I'll usually up the power, and if they're showing -5db or more, I'll usually lower it. Then I'll further adjust power based on the signal report I receive, sometimes taking observations of fading into account. If I answer a station calling CQ who then calls CQ again, I'll also up the power. Sometimes they don't hear me because I'm not the only station calling, but other times it's because they don't hear me as well as I hear them.

Wednesday, 8 July 2015

IRLP/Echolink Troubles

IRLP and Echolink on VE3YRC-VHF are down until further notice due to a computer hardware failure. The repeater committee is currently considering replacing the computer, but this will take some time to accomplish. The new hardware being considered is based on the Raspberry Pi single-board computer. As it contains no moving parts and consumes much less power, it should be much more reliable. Assuming the IRLP board is salvageable, the replacement should also be very inexpensive to purchase and operate.


Tuesday, 7 July 2015

And the winner is...

The coveted YRARC Field Day "Melted Coffee Pot" award went to Roger, VE3ROG, for a small oversight regarding a vital antenna connection on the 80m phone station. Quickly resolved through the use of sophisticated analysis tools and several pairs of eyes, it still held up operations long enough to be noticed by Steve VE3UT, our Field Day Director. So after Field Day operations were closed for another year, the proud tradition of presenting the award to the ham who created adversity, then overcame it, lived on. Steve also had the honour of presenting Roger with the award.

The award, now made more elegant through the efforts of Doug VE3VS who built the fine wooden base, provides room for plaques to honour winners for many more Field Days to come. You can see Doug below looks fondly down on the award, no doubt thankful for missing the opportunity to win it this year, turning in a fine score on the 40m CW station.

This is the fourth time the award has been presented, having been conceived in adversity with an unfortunate application of too much force (of the electro-motive kind) to a Field Day coffee pot. It is a testament to the tenacity of past winners that all of them were active in the 2015 event.

Congratulations to Steve for organizing yet another successful Field Day for the York Region Amateur Radio Club in 2015!