Waiting for Midnight.....

Happy New Year to you all!

While researching an Internet Radio using the Raspberry Pi, I found this:-

Well worth a look. A 'local' site with some insights into restoring 'veteran radios'. So we don't call them 'old'...
Also if you need some general info on the Barlow Wadley check here. 

Club Server

I found that power supply has a 'slow' fan. It needs oiling or replacing. I shall get to this in the next few days.

Club PC Sound Card

I have found the chassis sockets (3.5 mm) and a plate for mounting them on. Also getting to them in the next few days.

John ZS6WL 


Helical Aerials for H.F. - ongoing development

A long time ago I made an 11 metre CB aerial. It blew the locals away and I received complaints of 'bleeding'. When measured with a field strength meter it showed a strong field at 10 wavelengths away.

Now I have a beautiful H.F. rig, I need an aerial system. The receiving wire just does not cut it. I don't have lot of room for a full size 40 metre dipole. So I have looked into helical aerials again.

While I was shut down, yesterday afternoon, I got around to making my helical aerial for 10 metres. The storm passed and did not look like there was another in the line from the South West.

Not too pretty - yet. But it will be neater when finished. 

The 'source' document for this aerial is the 1978 Radio Amateur's Handbook from the ARRL. When I checked this section, it had not changed in the 1992 edition. So maybe there has not been much work done on it since...

John ZS6WL


2013 SARL Field Day

At about 10H00  on the 15th November 2013 we met at the Club House to collect all the equipment that was needed for the field day. We left the Club at about 11H00 and made our way to our destination for the weekend - Krugersdorp Game Reserve.

We arrived just before 12H00 and after setting up the tent we started assembling the antennas. This was the first time in anger that Noel ZR6DX erected his home made tower which is fitted to the front of his Land Rover. I must say it went up without a hitch and the TH-6 looked elegant up about 10 m. What a brilliant piece of engineering - well done Noel you can be proud of your effort.

The other antennas were a G5RV, hex beam and a loop skywire. We finally finished erecting the antennas at about 18H00. On Saturday night the natural elements turned against us and we were ill-treated by a massive thunder storm, howling wind and of course rain. At one stage we thought the big tent might be blown away. After a couple of hours the storm abated and we could continue operating again.

An enjoyable weekend was had by all who took the trouble to spend the weekend there. When the results came out we did not do as well as we had hoped, but still managed 3rd place. Please follow the link below to see the pictures taken during the weekend.


Geoff Levey  ZS6GRL



But Wait, There is more!

As promised last night, I am uploading the later pictures of the club's PC. 

Having discovered that the heat sink fan assembly had a broken clip. I started to look around for a replacement. Of course the mounting holes on this "veteran" PC are different from the newer or latest fans. Luckily I had a broken motherboard lying in the garage. I proceeded to un-clip the identical assembly from the motherboard. I am glad I did, it taught me a lesson. The plastic pins that go through the pcb have small white plugs that need to be unplugged before you can remove the housing.

So I now had to disassemble and disconnect the motherboard from the chassis. Before forgetting where all the wires are plugged in, I took a picture.

My memory is not what it used to be. The phone's camera has proved invaluable for close up records of all sorts of things. Now I unplugged all the wires and unscrewed the mounting screws...

On the bottom of the motherboard:
It also confirmed the date of the PC's making. As I later discovered that the version of Windows XP was in fact the original. It was never updated because the installer had turned off the automatic updates. Windows XP was not even service pack 1 !

I then started to clean the cpu and the heatsink.
 Cpu looking clean and shiny.

Hey wait a minute! What is that on the heat sink? After I had removed the large amount of thermal paste, I found the other thermal pad...
Which of course had never been used. So I unpeeled the pad to find this extra thermal transfer pad had never been used... No wonder the cpu got hot. It was working under a 'blanket'.

So I cleaned that off the aluminium heat sink as well. Re-applied some new thermal paste to both cpu and heatsink. Putting to good use an old credit card to smooth the paste onto the cpu and the heatsink and into a thin layer. The paste is only there to smooth out the rough surfaces of the cpu and heatsink. Also to present as little as possible 'thermal resistance'. So the heat generated in the cpu can be radiated away as efficiently as possible.

I put the PC back together and plugged in all the wires. Checked carefully that the plugs were all in/on the right pins/sockets. Then switched on. First I got into the BIOS setup. Only to discover - yes the battery was 0.5 Volt - flat. It should be 3 Volts. Replaced the battery. Switched on again. now the cpu temperature reached 42C and settled at that after about 5 minutes.

Then I booted the PC to Windows XP Professional. Only to find out that it was the first ever version of XP. Service Pack 3 will not install on anything less that service pack 1. The following six hours are a blur now... Now you know why I call it "Windwoes". At about 19:30 I switched it off and put it into the boot to take to the club.

Maybe some more later.

73 John ZS6WL 



When I was at the club on Saturday, I took charge of the club's PC. This was pre-arranged and as the operators now bring their own laptops, I could remove it from the club.

Geoff ZS6GRL, had told me already that there were 'issues' with the PC. It would hang and he 'cured' the 'issue' by removing the display card and replacing it...

Well, when I got it to the workbench, I switched it on and it told me to 'Check System Health!'. So I did...

69C is far too high for the cpu after just switching on.

It is an 'old' PC and the assumption is that the thermal paste has gone bad...
But when I opened it up and checked the heat sink assembly and fan, I found this :-

I could not believe my eyes. There is the remains of a label stuck to the cpu! It has about a third of the thermal transfer area insulated from the heat sink.

I also had discovered that the plastic retaining clip had broken on the fan assembly. The remains can be seen at the top area. Obviously this has to be cleaned and the plastic retainer replaced.

Some of you reading this will already know about 'Murphy's Law'. This is one instance where he would jump in. This is an 'old' PC with an old fan assembly...
Of course the new [modern] fans will not fit the holes on the motherboard...

Part 2 to follow, after I have fixed the PC.
John ZS6WL



Ubuntu Amateur Radio Software - fldigi and others

I have just caught another link from a Radio Amateur who is using the Raspberry Pi to test his H.F. filters...

But that is not what I wanted to blog about. It is this:-

I was looking for an 'equivalent' to HRD but for Linux Ubuntu. This PC and OS (operating system) has proven to be the most useful for my hobby, Amateur Radio. So whilst I had already compiled the beacon program for Ubuntu. I wanted to see if there was anything else.

fldigi is available for Windwoes as well. So those of you with XP etc, can now make use of the 'open source' software as well.

Maybe you should read this first:-

This all came about because the latest Elektor Post arrived in my inbox and this caught my eye:-

Wow! He only did it to please the RSGB...

Some reading for the weekend and those not going on the field day.
John ZS6WL 



Ham Nation Video Collection - whole series


73 Geoff Levey ZS6GRL


History of contesting
The origin of contesting can be traced to the Trans-Atlantic Tests of the early 1920s, when amateur radio operators first attempted to establish long distance radiocommunications across the Atlantic Ocean on the short wave amateur radio frequencies. Even after the first two-way communications between North America and Europe were established in 1923, these tests continued to be annual events at which more and more stations were successful in establishing two-way contacts over greater and greater distances. In 1927, the American Radio Relay League, which had been principal in organizing and publicizing these tests, proposed a new format for the annual event, encouraging stations to make as many two-way contacts with stations in other countries as possible. The 1928 International Relay Party, as the event was renamed, was the first organized amateur radio contest. The International Relay Party was an immediate success, and was sponsored annually by the ARRL from 1927 through 1935. In 1936, the contest name changed to the ARRL International DX Contest, the name under which it is known today.

One of the best ways of getting the most out of your investment in amateur radio is to take part in contests. In South Africa we have numerous contests that mostly take place over weekends which gives you the opportunity to compete against your local peers. There are also plenty of overseas contests where you have an opportunity to test your skills against your international peers. Your level of intensity in these contests depends on whether you just want to take part for fun or aim on winning the contests.
To explain more about the terminology you will encounter in contests, I have taken the following FAQ (Frequently Asked Questions) from an article written by Andrew Roos ZS5AA with his permission

Everyone has their own reasons. Some of mine are: to sharpen my operating skills, to learn to get the most I can out of my equipment, to compete against my peers, to be a part of the community of contesters.

The winner in each category is the station which gets the most points in that category.

Each QSO will score a certain number of points. The number of points scored for a QSO may depend on the location of the station contacted - for example in the CQ Worldwide DX contest stations on the same continent as yourself count 1 point each, stations on a different continent count 3 points and contacts between two stations both located in North America count 2 points. In other contests, QSOs for certain stations may count for more points than QSOs with others - for example, in the ARRL 10m contest, contacts with stations holding Novice or Technician Plus class licenses count more than contacts with other license classes. In contests which allow you to work in different modes (for example, CW and SSB) the number of points may also depend on the mode.

As well as getting points for each QSO, most contests allow you to get multipliers from certain QSOs. For example, you might get a multiplier for every different country ( DXCC entity) you work on each band during the contest. Your final score for the contact will then be calculated by multiplying the total of all your QSO points by the number of multipliers you worked. For example, if you worked 100 stations at 2 points per QSO and 20 multipliers, then your total QSO points would be 100 x 2 = 200, and your multiplier is 20, so your final score would be 200 x 20 = 4000 points.

Entities correspond roughly to countries and administrative territories, but they also may be islands and even reefs if they meet criteria set by the ARRL, which administers the DX Century Club (DXCC) award and decides what qualifies as an "entity".

Scarborough Reef

The world is divided into 40 "CQ Zones" which are used as multipliers for some contests. Get further information and a map showing the different zones at www.cq-amateur-radio.com/wazmain.html.

That depends on the particular contest. Some contests are limited so a single band - for example, the ARRL 10m contest is (not surprisingly) for 10m only. Many contests allow operation on all the pre-WARC HF bands - that is: 160m, 80m, 40m, 20m, 15m and 10m. Other contests are for VHF bands only. However note that contesting is never permitted on the WARC bands: 30m, 17m and 12m. This is so that amateurs who do not enjoy contesting can take refuge on the WARC bands during contests.

The WARC bands are the 30m, 17m and 12m bands. They were named after the World Amateur Radio Conference in 1979 at which these bands were allocated for amateur use. The WARC bands may not be used for contesting.

Different contesters have different preferences and budgets. Some like to work on their own, others prefer to be part of a team. Some can afford high-power stations, others prefer to compete with a "barefoot" or QRP transceiver. By dividing a single contest into a number of different entry categories, all contesters can share the fun and contribute to the contest, while competing against similarly equipped stations in the same category.

That depends on the contest, but the entrance categories for the CQ Worldwide DX contest are a good example of a fairly extensive list of possibilities:
  • Single Operator High - a single operator, maximum power 1.5 KW, no DX alerting assistance (for example, DX cluster spots) allowed.
  • Single Operator Low - a single operator, maximum power 100W, no DX alerting assistance allowed.
  • Single Operator QRPp - a single operator, maximum power 5W, no DX alerting assistance allowed.
  • Single Operator with DX Spotting Net (also called "Single Operator Assisted") - a single operator, maximum power 1.5 KW, passive use of spotting nets allowed.
  • Multi-Operator, Single Transmitter (also called "multi single" or "MS" for short) - any number of operators, but only one transmitted signal allowed at any time. The additional operators will often be listening for new multipliers, and passing the information on to the one transmitter operator.
  • Multi-Operator, Two Transmitter (also called "multi two") - Any number of operators, but only two transmitters. In CQWW, both transmitters may work any stations. In some other contests there are strict restrictions on what the second transmitter may do - for example, it may only be allowed to work new multipliers.
  • Multi-Operator, Multi Transmitter (also called "multi multi") - Any number of operators, operating any number of stations, but with only one transmitted signal on each band at any time. In many cases a "multi-multi" station will have a dedicated transmitter for each of the contest bands.
Note that in CQWW, single operator entries can choose to be all-band, or only to work a single nominated band.

These are all abbreviations for contest entry categories:
  • SOLP - Single Operator Low Power
  • SOHP - Single Operator High Power
  • SOAB - Single Operator all band
  • SOSB - Single Operator Single Band, often includes the band, e.g. "SOSB/80" for a single band entry on 80m
  • M/S - Multi/Single - Many operators but only a single transmitter
  • M/2 - Multi/Two - Many operators with two transmitters
  • M/M - Multi/Multi - Many operators with many transmitters
It is a worldwide computer system on which DX stations are reported ("spotted"). It can be accessed via Packet Radio or on the Internet at www.dxsummit.com. You are only allowed to make use of DX Cluster spots if you are entered in an "assisted" class. No matter what class you are entered in you may not enter your own station into the DX cluster, this is called "self spotting" and is illegal in all contests.

To make a serious attempt at an international contest, yes. Most of the smaller stations that enter a contest spend much of their time answering other stations that are calling CQ. This is known as "search and pounce" - you search for a station you need, and then pounce on it by replying to its call. However since you can only work a station once on each band and mode, before you reply to the CQ, you need to know whether you have worked the station before, and unless you have a photographic memory a computer logging program is by far the best way to do this. Contesters are a very friendly bunch, but calling the same station five or six times on the same band during a major international contest will test the patience of even the most saintly participant. Of course if you are fortunate enough to be even moderately rare DX (ZS for example), then you can get by with calling CQ yourself and waiting for a reply, log this on paper and later remove the duplicates ("de-dup" the log) by hand. This is what I did in my first major contest, but after manually de-duping 475 QSOs, which took me a whole day, I went out and bought a logging program.
Note that for many of the smaller state or national contests, you can get by without a logging program as there are few enough entrants that you can remember who you have worked or look it up on your paper logs. These contests can be great fun and are excellent practise for the "big ones".

There are many different, some commercial ones, which you have to pay for, and some which are free. Popular commercial programs include WriteLog for Windows, TRLog and SD. Writelog has a Windows graphical user interface. Although originally written for DOS, TRLog will also run under most versions of Windows. SD is available in two versions, one which runs character-mode under Windows, and one for DOS. Free contest logging software includes CT, also originally designed for DOS, and the open-source N1MM logger for Windows.  N1MM has been adopted by the SARL as the logging software that is recommended. N1MM is the only logging program that has  all the templates for our contests included which makes it a pleasure to use.

First, be aware that logging programs come in two different flavours - general logging programs designed to maintain a normal station log, and specialized contest logging programs. The difference is that contest logging programs have contest scoring rules "built in" for major contests, so they will automatically keep track of your score, tell you whether you can work a particular station for the contest, and other contest-specific time saving features. Needless to say, you want a program designed for contest logging. Then make sure it supports the contests you want to enter, since having the contest programmed into the software for you is a real time saver. If you don't know exactly which contests you want to enter, then at least see how many contests it supports. Also consider the ease of adding new contests yourself if you have to. Some programs, like WriteLog for Windows, require programming skills to do this while with others, like TRLog, you can add new contests by editing a configuration file. Also look for a program that can interface with the rig(s) you use or are likely to use. Having the logging program automatically pick up the band and mode your rig is set to is a great time saver and eliminates a common source of costly errors. Many logging programs can also turn your beam automatically for you to point at the station you are working, so if you want to use this feature then make sure the program is compatible with the rotator(s) you are using. Finally, make absolutely sure that the logging program can export the log file in the standard "Cabrillo" format, which is used to submit logs for most contests. All decent logging programs can interface to your rig's key jack to send CW automatically. This is a great feature as it allows you to send exchanges while capturing information into the logging program.

Cabrillo is a standard format for submitting log files to contest organizers so they can be checked and scored by computer. Although different logging programs store the log files in different formats, most have the ability to export to Cabrillo format for submission.

There are a couple reasons to connect your computer to your rig. First, so it can send CW automatically and/or PSK31 or RTTY depending on the contest. Some logging programs also provide a "voice keyer" which allows you to record messages and then replay them over the air. This is great for calling "CQ" in a phone contest, for example. For this you need a computer soundcard interface with support for CW keying. A simple example can be found on my web site. The second reason is so the logging program can keep track of the band and mode of your transceiver. This may require a proprietary interface from the transceiver manufacturer. Many of these interfaces will also allow the computer to control the transceiver, so for example you can change frequency simply by typing the new frequency on your computer.

Just the rig you use every day. That's not to say that some rigs aren't better for contesting than others, but just about any rig will do to start. If you plan to buy a new rig for contesting, then look for one with a "strong" receiver which can receive weak signals in the presence of very strong signals without overloading. The "blocking dynamic range", "intermodulation dynamic range", "third order intercept" and "phase noise" specifications found in most technical reviews are important indicators of this.
Also, note that it is a good idea to have your commonly used functions such as filter selections, if width and shift (if available), notch filter, attenuator, RF gain, mode, and band switch available on the front panel, to avoid having to wade through a menu system in the heat of battle. This means that the compact transceivers designed primarily for mobile operation may not be the best choice in a contest. The ability to interface the rig to your computer so the logger can automatically enter the correct band and mode is another useful feature that is found on most modern rigs. A narrow (250 or 500 Hz) filter is almost essential for CW contests.
Amongst current production HF transceivers the Elecraft K2, Icom IC-756 Pro 2, Ten-Tec Orion and Yaesu Mk V FT-1000 MP are some of the best. However note that these are not beginner's radios (with the possible exception of the K2, but this must be constructed from a kit and so is best suited to someone with prior construction experience), so if you have no prior operating experience it may be better (not to mention cheaper) to start off with an entry-level or mid-range radio. There are also some excellent radios available at very reasonable prices second-hand, such as the ICOM IC-765, Kenwood TS-850S, Ten Tec Omni VI Plus and the Yaesu FT-990 as well as earlier versions of the FT-1000 (both the FT-1000D and the original 'MP are excellent radios) and the IC-756 Pro.

The object is to make as many QSOs as possible in a limited time, so "QSO rate" - the number of QSOs per hour - is (almost) everything. Hence all "unnecessary" parts of the QSO are omitted, leaving only the required essentials - call signs, 599 signal reports and a serial number or zone number if required by the rules. Be sure to check the rules to see what the required exchange is for each contest you enter.

Read the contest rules and decide which category you will enter. Test your station and antennas. Have a look at the expected propagation and draw up an operating schedule showing when you expect to operate on which bands, and where your beam will be pointing. (This schedule will change during the contest as conditions unfold, but you should at least have an initial plan.) Stock up on fast food - microwave meals are my favourite. Set up your computer, check that the logging program is interfacing with the PC correctly, and ensure that you select the right contest in the logging program. Try to get as much sleep before the contest starts as possible so you can work long hours during the contest itself. Feed your pets. Read the contest rules (again) and make sure you understand the exchange format, multipliers, sequence numbers, entry categories, power restrictions etc. Accurately set your computer clock so the QSOs will be logged at the correct time.

In order to be listed in the results, you will need to submit your log to the contest organizers. Most of the major contests these days prefer electronic logs, usually in Cabrillo format, as they can be automatically checked and scored. Smaller (e.g. national) contests may prefer paper logs. In most cases if you have not used computer logging then paper logs will be accepted. However many contests will not accept paper logs printed by a computer logging program. After all if you have the log on computer then they don't want to have to type it in again. The address for submitting your logs can be found in the contest rules.

"Massaging your log" - for example, checking callsigns in a callsign database and then correcting those found to be in error - is generally frowned upon by contesters, although it may not be strictly illegal.

A "busted call" is a call which you captured incorrectly during the contest. You will generally lose points for busted calls or incorrectly logged serial numbers.

If you are responding to a CQ, then wait for the station to call CQ again so you can copy the call correctly. If you are calling CQ, then send "CL?" and the other station will repeat his or her callsign. If conditions are poor, then you may have to ask a couple of times, but this is much better than getting the callsign wrong - which will cost you penalty points for the contest - or not entering the QSO in your log file, which is very unfair to the other station and will cost him or her penalty points. Note that although some programs (e.g. WriteLog) have the ability to mark a QSO as "unclaimed", the Cabrillo format used to submit contest entries has no such mechanism, so QSOs marked as "unclaimed" in the log file will just not be included in the Cabrillo file. It is very bad karma to do this unless you are absolutely sure that the other station knows they are not in your log, otherwise they might submit the QSO and be penalised for it.

You hear unusual callsigns during contests for two reasons. First, some administrations reserve special short or unusual callsign sequences specifically for use during contests. For example, in Britain callsigns with a single letter in the suffix like "M5A" or "GM1A" are reserved for contest use. In France, the prefix "TM" is allocated to contest stations rather than the more usual "F" prefix, for example "TM6X". A short callsign gives the station an advantage because it is faster to send and less likely to be copied incorrectly. Unusual prefixes are attractive because in some contests like the CQ Worldwide WPX (Worked all Prefixes) contest, each unique prefix counts as a multiplier, so the more unusual prefixes will attract more calls. That happens in other contests as well.
The first time I heard a "TM" station I was convinced I had found some rare DX, and was somewhat disappointed when I discovered it was located in mainland France. Some countries have even issued callsigns without a digit following the national identifier. For example, the callsign "D4B" is issued by Cape Verde which has the national identifier "D4", so there is no digit following the national identifier - the "4" is part of the national identifier. However Article 19 of the ITU Radio Regulations was amended by the World Radio Conference 2003 (WRC-03) making it mandatory to have a digit following the national identifier, so it is likely that such callsigns will be phased out.
Another reason for unusual prefixes is that many stations operate temporarily from a foreign country, usually to make themselves more sought after in the contest. For example, American stations are two a penny in most contests, but an American visiting the Bahamas is an attractive multiplier. Operators visiting a foreign country may be allocated a "normal" callsign for the country they are visiting, but will often use their home call either preceded or followed by the country (and possibly region) prefix of the country they are visiting. For example, KD4D operating from South Africa would use the callsign ZS/KD4D, while the same station operating from Canada would use a callsign like KD4D/VE3. Note that the Morse code for the "/" symbol is "dah-di-di-dah-dit", and it is pronounced "stroke" on phone.
Unfortunately there is no standard as to whether the national identifier of the country being visited should precede or follow the home call. The CEPT agreement, which is the largest reciprocal licensing arrangement covering Europe, North America and some other countries, specifies that the national prefix should precede the home call. However other reciprocal agreements, like the one between the United States and Canada, specify that the national identifier should follow the home call and even within the CEPT agreement there is one exception (Peru).
Also note that following WRC-03 it is now legal for amateur callsigns to have a suffix of up to four characters (even more for special event stations), and the suffix may use both letters and digits provided that the last character is a digit. So in future contests you may hear callsigns like "ZS1234A" or even "22222A"! The latter would be from Britain, which has been allocated the national prefix "2".
So the best advice on callsigns is to expect the unexpected, and log each callsign exactly as received.

If you are using Logbook of the World then by all means. If you are using QSL cards then this is likely to take a lot of time and money due to the number of contacts made in a contest. My policy is that in contests I only QSL on request, which normally means the other station sending me a direct QSL with a self-addressed envelope. This differs from my normal non-contest policy which is to QSL every contact via the bureau unless otherwise agreed. But whatever you decide, please don't enquire about QSLs on air during the contest. If you work a station you need, then QSL direct with a dollar bill or IRC after the contest.

73   Geoff Levey ZS6GRL


Thanks Willem!

Thanks Willem!

At last some 'input' from a committee member. He sent me this link:-
Symmetrical Matchboxes 

Which has another link to the 'S-Match' here:-

These links have a very interesting proposition for balun fed 'symetrical' matching circuits for aerial feeds. They also have core information for use with moderate power levels. (100Watts)

John ZS6WL


We don't want 'Out of Date' News

The Anode was always 'out of date' by at least a month. As the articles were gotten from other amateur radio web sites or scanned/ocr'ed from old magazines. 

So the members and others would 'send' the latest interesting news to 'the club' via the Club Magazine. I don't think I will stop 'processing' old 73/QST/HR magazines. As they always provide 'food for thought', at least to those of us who are dedicated 'experimenters'.
The appeal was for 'articles of interest' to the Amateur Radio members. So if you come across anything of interest to you as a radio amateur, please email it to the club's email address.

Committee members can access and post 'blog's'. So you can send it to your 'favourite' committee member, if you like.

The picture used in the talk on Practical Baluns caused quite a stir. A spray on aerial? Wow! 'Wearable Technology' is starting to get more interesting. However I don't think we are going to be working somebody on 40m at full legal power just yet... Wearable Technology 

Perhaps it is because I was brought up before the advent of 'spell checkers' but this email from QRZCQ.com, got to me:

"Your profile page was viewed 131 times, please check you profile to ensure other hams can look up the right data about you!" --- YOU PROFILE !!! 

Take a look at this site... Ham Hacking
It might interest you.

John ZS6WL



More "input" needed!

Last night's committee meeting was fun. Lots of subjects for discussion. But one thing is still outstanding...

MORE INPUT for the ANODE Please!

Whilst researching for the upcoming presentation, I have come across some interesting facts, figures and pictures.

 Well of course it advertises Pringles. I am sure that the designers of the cardboard 'can' had no idea it could be used to collect WiFi signals from far away. However this one shook me...

This is an aerial! Almost spray on type...

My First HF Beam http://www.qsl.net/ke6d/my_first_hf_beam.htm

How do we make an HF station work more effectively? :: HFRadio.org

And remember, "Marconi spins in his grave every time a ham buys an aerial instead of building it !  ( W1GFH )"

Are you worried that XP has only six months to live?
How businesses can cope with the looming Windows XP deadline
This is definitely a site to read. 
The definitive e-book on Power Quality



Last Night at the 'Bring and Fix' Meeting

Last night saw me (ZS6WL) bring the PA to the club. 
This will be used at the upcoming Flea Market for announcements.
There was a great turnout last night. Roy showed off his re-constructed LC meter that he built. When he showed me his capacitors to calibrate it, he only had electrolytics and tantalum types. So I promised to find him some 1% capacitors that he could use to calibrate the C meter.

I found that the LC meter is now incredibly popular with everyone. When I did a search for the calibration procedure, I found quite a few sites with revised designs and updates.

So today I was hoping to get some of the other committee members onto the blog. But so far no luck. 

Back to the grindstone...

John ZS6WL 


Just what is " homo ludens radiactivus " ?

Oh Wow! What a page! Homo ludens radiactivus [I am not surprised the spell checker doesn't like it!] It is the story of a young radio amateur growing into the hobby. Well worth reading.

Another that caught my browser's attention recently is:  
A $40 Software-Defined Radio

Then there was the announcement of a 3D scanner. Could this be the origin of the 'replicator' ? Makerbot Digitizer: Desktop 3D scanner goes on sale 

73 John ZS6WL


Its Saturday afternoon

Its Saturday afternoon. I have just fixed the APRS PC. Actually I replaced the power supply which had been taken out by lightning. This was some time ago but noone seemed to care...

At the recent committee meeting, it was stated that we should get the APRS going again. So I offered to fix it.

This week like others I came across a number of links of interest to members of the club. Here is a small selection:-

Blogs with 'weakest of the weak' passwords hijacked to build mystery bot army
Wordpress, Joomla, Datalife Engine - they're all under cyber-crims' control
By John Leyden, 8th August 2013

Bristol scientists use urine to charge mobile phone

How much are old home computers worth?

PC sales see 'longest decline' in history

Buttercup the Duck gets prosthetic 3D-printed foot

Pair of PC viruses help each other survive [somebody read the Jargon File about Friar Tuck and Robin Hood]

The teenage radio enthusiasts who helped win World War II


The Anode for July 2013

Hi all

This is the July Anode for 2013 in html format.

If you know of a new member, please forward this link to them.
Ask them to email me with their details (name etc.), and I will add them to
the email list.

John Brock
(formerly ZS6BZF, now ZS6WL)

NOTICE - This message contains privileged and non-confidential information
intended for the use of Radio Amateurs. If you are not the intended
recipient of this message, you are notified that you may disseminate, copy
and take action based upon the information contained therein. If you
received this message in error, please read it, maybe it will entice you to
try Amateur Radio as a rewarding hobby.

ZS6WR page: http://www.zs6wr.co.za

----> more 
Volume 14, Issue 1


Inside this issue:

Editor’s Comments


Editor’s Comments

Like it or not, the Anode has to change with the times. As a hobby, Amateur Radio is changing rapidly as technology changes. We should try and keep up.

When I started the new Anode in 2000, I did not think the format would change from the long standing one. But it did. Once upon a time this was typed on a typewriter and 'Roneo-ed' off to be mailed to members monthly.

Later it was typed on a typewriter and then photocopied on a Xerox machine. And then mailed by the Postal service to members.

The cost of mailing was not onerous as many people used it. So the costs were spread over many 'clients'.

With the advent of email, things started to change quite rapidly. Printed copies were replaced by Portable Document Format (PDF) files. When I started sending the Anode out, I kept the file size to below 0.5MB. As most members were still on 'Dial up'.

Also in those 'early days', I used a desktop publishing software package called Microsoft Publisher. It came with my copy of Microsoft Office 2000 Professional. This laid out the Anode in a nice format and outputted the file in Postscript format.

Postscript is what the lasers use to set up pages before throwing carbon granules at the paper. It is the base of a PDF. So a quick transformation to PDF was done by GhostScript/GhostView. This last piece of software was 'Open Source' and free.

When my office applications started to crash for no apparent reason. The help would send you to the Microsoft Office upgrade site, to get you to buy the latest version. I turned to using the Open Office package. But this did not have a 'Publisher'. It did however have an export to PDF function. I carried on using Microsoft Publisher.

I tried out new layouts on various members. I got no reaction. Finally I got some positive feedback for a new format that I had laid out in the Open Office word processor.

With this 'new and improved' format came some nice features. The 'clickable links' allow the reader to jump to articles and web sites. [That one takes you to the club's web site.]

I believe the time has come to change the Anode's format once again to a multi-contributor blog. Having more than one 'contributor' will mean fresh articles and news. No longer will the members wait for a whole month for the latest articles and news.

Amateur Radio is progressing at an ever increasing rate. It is no longer 'wireless' nor Heathkit construction projects. There are still unexplained and untried areas. One of which is the compact H.F. Aerial for use in cluster housing areas.

Recent events in Amateur Radio have shown me that the latest and most exciting developments are in the use of technology available right now. Software Defined Radios (SDR) are being released at an ever increasing rate. Use of small micro systems such as the Raspberry Pi for various functions are appearing on the web sites daily.

In South Africa, we have an 'issue' with high technology and electronic components. We remain a small market with very few friendly manufacturers. When a chip gets used overseas for a new and low cost SDR, we will not see that chip here until it is used in a mass produced box.

A recent example is the Realtek RTL2832U which is available overseas for $20 (R200). This chip can do the SDR function from 54MHz to nearly 2GHz. It even has a USB2 interface! So you can plug it into your tablet and listen to the Sunday bulletin on 2 metres narrowband FM.

[for example] A $40 Software-Defined Radio

The Club is now going into a new year with a new committee. In the Northern Hemisphere, Winter is the time for new projects. I have an H.F. And VHF/UHF Aerial system to make. Recent events have made it impossible to give more time to the Club. So I need some assistants...


West Rand Amateur Radio Club – ZS6WR News

Digital Modes Talk

Noel Hammond ZR6DX, gave an interesting and well presented talk on Digital Modes in amateur radio at the West Rand Club House. Noel spoke on everything from the beginning of digital modes, their inception and progression, right up to their use in modern day amateur radio. The main object of this talk was to introduce fellow hams to the digital modes world, using Ham Radio Deluxe's digital modes software called DM 780 (Digital Master). We were guided through everything from the initial setup, basic operations, use of macros and most of the important functions one would generally us. The different digital modes used, as well as band width per mode, the speeds of each and their general usage throughout the HF bands were explained. The main focus was PSK31 and RTTY as these seem to be the most popular modes in use today, however there are many to choose from.

Noel also delved into the setup of the logbook functions in HRD and the syncing of this logbook with online sites such as qrz.com and lotw.com (Logbook Of The World). Noel demonstrated how each copy or backup of a logbook is made and the advantages of using the online resources to streamline your digital logbook and make sending and receiving of operator/station data while using Digital Master or HRD simple and effective.

The basic setup required to connect a radio to your pc using CAT and sound card interfaces was also explained during the talk. Noel described how these can be purchased locally or online, and that a home brew version is simple and cost effective to build. Phillip ZS6PVT was on hand with home made interfaces which he made available to those present.

Along with the talk we were provided with a CD containing all the software needed. Also included were PDF documents which included everything from schematics to course notes. A detailed 50 page booklet was handed out which followed along with Noels Power Point presentation for easy reference.

At the end of the day, an HF station was setup and PSK31 was demonstrated live. Those who stayed were given the opportunity to make a few digital contacts.

Overall the talk seemed to inspire all those present, and the response was extremely positive. Noel should be commended for the amount of work he put in to presenting an informative and easy to understand talk on Digital Modes and HRD. At the end we were all more knowledgeable in the use and operation of digital modes.

Here is what a fellow attendee had to say on his blog regarding Noels talk.

Noel plans to hold another digital talk in the future due to popularity and interest in this one. Keep your eyes and ears open for more info.


EH Aerials
In message <kt5ls2$13m$1@dont-email.me>, KaFKaesque
<kafkaesque@g4kfk.co.uk> writes
> [quoted text muted]

I've commented on this before.
I made an EH antenna for 14Megs to a variant of the W0KPH design. It's a similar concept to the CFA.

www.b-howie.demon.co.uk/EH_14MHz.JPG .It's about 40cm long .

It looks a bit foosty as it was outside for about 6 months.

The way it works is that a 1/2 wave dipole generates the H component from the high current in the middle and the E component from the high
voltage at the ends . The length of the dipole gets the 90degree phase shift. The EH antenna does this by moving the ends of the antenna closer together by a combination of capacitance and inductance loading. It's not fundamentally wrong, it's just not as efficient as a resonant dipole.

It radiated and received OK and didn't get hot even with 200W going into it. I managed to work a few people on it.

I've got some aluminium beer cans and was thinking of making one for 10MHz to use on WSPR.

I don't think I'd spend good money on any of the commercial ones.

Anyone else tried one ?

Brian GM4DIJ
Brian Howie


So I made a phase detector – Automatic Aerial Tuning
Geoff said that the original QST article was too technical and it used valves. It predates the 73 Magazine article, which I put into the Anode some years ago. [January 2002 Anode – the Tennamatic]

I did a search (on Google) for “Phase Detector”. I got very little in the way of circuit examples or explanations.

Why use a phase detector, instead of an S.W.R. Meter?
Going back to basic principles, you need to find the 'resonant frequency' of your aerial system. If it were a simple tuned circuit, at the resonant frequency, the reactances are cancelled out. The circuit becomes resistive as L and C resonate. The resistance won't be exactly what you want of course. It will need matching to the feedline. Also thanks to Murphy's Law, the resonant frequency won't be in the Amateur Band. This is why you use an aerial tuner.

Basic Circuit (above)
The diodes are OA91 or similar germanium diodes. Suitable for QRP work up to 10 Watts or so.

Circuit Explanation
The transformer is a current sensing transformer. The load voltage portion is used to switch on and off the diodes. This switched or chopped current waveform gives an output voltage that reaches a maximum at + and – 90 degrees phase. When the current and voltage are in phase or anti-phase (180 degrees) the output will approach zero.

This 'simple' circuit was fed from a signal generator at 0dBm to +10dBm and the frequency set to 7.000 MHz. With a 51 Ohm resistor as a 'load', it gave a reading on the DVM [Digital VoltMeter] of a few millivolts. Connecting a 220 pF capacitor across the 'load' gave a larger reading. As did an inductance of 2.5 uH connected across the 'load'. The readings were small but of opposite polarity. I found that as the signal generator was just about turning the diodes on, the voltage feed needed to be an 820 Ohm resistor and the other resistor an open circuit. Infinity Ohms – badly drawn on the sketch.

Here is what it looks like as a 'prototype':

Yes, I could have put more turns on to the toroid to build up the inductance. But I was aiming for a 'test circuit' to prove the circuit. It works and is really only suitable for QRP operation and shows the basic circuit in operation.

The circuit needs to be made more 'sensitive' to the zero / 180 phase shift point. So I am going to develop the circuit further. I will let you know what I find.

Now for the transistor version... JB 2013


The West Rand Amateur Radio Club
Established in 1948

KG33XU 26.14122 South - 27.91870 East

P.O. Box 5344
Weltevreden Park
Phone: 082 546 5546 (Chairman)
Email: zs6wr.club@gmail.com
Web page: www.zs6wr.co.za

Bulletins (Sundays at …)
11h15 Start of call in of stations
11h30 Main bulletin start

145,625 MHz (West Rand Repeater)
Output: 439.000 MHz 7.6 MHz split
Input: 431.4 MHz (West Rand Repeater)

HF Relay when possible on 7140 kHz
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