Some Safety Facts


How often do you check your ground GFCI or ground fault circuit interrupter. Those working with 220V appliances know how important this is to your own safety. So much so that I don’t know of anyone actually testing their domestic GFCI on a regular basis. From a safety angle they should be checked at least once per month.

Bench saws and angle grinders. The DIY’er sadly never inspects the condition of the blade of his saw or cutting disk. Do we use safety goggles?  A good pair of safety googles cost a few U$ but yet I see so few people using them.  Is this for the lack of safety knowledge or time taken to put them on.

Lighting is a serious problem in many work places but employers don’t see the dangers of a) inadequate lighting or b) faulty lighting. Flickering fluorescent tubes can trigger an epileptic fit.

Companies pushing staff to wear safe shoes in their working environment often don’t see the merits of chcking the soles of these shoes. A hard toe cap means nothing if the sole has no strength. Even more so, have you seen the effects of a beautiful polished floor when it’s wet?Money mouth

Not so long ago we were bombarded with safety literature which covered the dangers of cell phones and microwave energy. Now we hear nothing. Does that mean that microwaves are now safe. The same people that discarded their microwave ovens for more conventional cookers have cell phones attached to their ears every minute of a working day. Makes one think doesn’t it?

And then we have hot topic number one – the south african taxi driver. Why worry about safety in the workplace when your employees may not get to work in one piece in any event. Yes, the traffic department is charging these lawbreakers but sadly the yellow line is still a taxi stop, a no-u-turn is still a sign showing ‘danger – sharp curve to the right’ (here in any event) and of course, when taxis strike the entire nation comes to a halt. Amazing to think that the private transport system controls the entire nation.


Electronics: Common Questions


The magnetic amplifier. What is it? This device, using saturable reactors and the non-linearity curve of specific transformer cores are used in HVDC measurement and certain types of welders.  And of course, pre-digital age we had the arithmentic logic unit (ALU) which utilised tubes and transformers for summing in early mainframes – this was the 1950s folks so everything was big, bulky and of course heavy. Go to Wiki or for more information.

Magnetrons and Klystrons – a guide to early radar. The magnetron is not only used in microwave ovens, it’s also the device used in radar for radiating RF power. Early radar also used Klystrons for the receiver front end (this was the reflex Klystron used as the local oscillator) – both devices use resonant properties of their cavity. Klystrons are also used as particle generators and in UHF transmitters. I’m sure there must be many readers out there that worked in the radar industry that can recall the time taken to tune in the klystron local oscillator to get maximum output in the radar front end. I do.  Klystrons are no longer used in radar (to my knowledge) in the receiver front end haviong been surpassed by semiconductor devices. Wiki has an interesting article on klystrons.

TR Tubes. A problem with radar is of course that the same waveguide carrying the output RF is fed into the front end. The front end is a very sensitive device so what stops all this enrgy from blowing the front end to pieces. Situated in the waveguide at carefully calculated lengths from the transmitter and receiver are ATR and TR tubes which switch the energy to the required path. (actually blocking or passing through a short circuit) There are fundamental issues with this as explained in this interesting article by this Radar Tutorial. Radar engineers will recall that a TR tube never failed without one having to replace the Xtal Diodes in the front end as well. Money mouth. The TR tube containes Tritium gas (radioactive isotope of hydrogen = H3) and also had a keep alive voltage applied to an electrode. Radar engineers will recall that this keep alive voltage used to also fail.Money mouth

Klystrons were been superceded by Gunn oscillators in the local oscillator stage when I stopped radar repair twenty years ago.  Gunn oscillators were strictly made of Gunn Diodes (a Transferred Electron Device. Gallium arsenide devices are practical up to about 200GHz) which were practical for radar usage in the X-Band spectrum (3 cm). I didn’t find much about Gunn Ocillators on the web without having to pay for a book so if readers can lead me to an interesting website I’d love to hear about it.

Submarines have a very serious problem: Communication. If you feel you are up to it and can develop a submarine radio telecommunications system under cover without your neighbours getting wind of it you should be serioulsy looking into this technology to make some serious money. Up to now submarines receive radio traffic at a very low frequency (actually ELF – extra low frequency 3 – 3000Hz) and if they wish to transit have to release a buoy to the surface to communicate effectively. Water, especially salty water is not known for it’s friendly radio communication ability. Of course the US navy is not going to tell you about their latest communication techniques, neither the Russians, French or Brits but you can bet your bottom dollar that there have been advancements made in this field but possibly not much.  A new system? Read here. Sounds like an old system to me.

And last but not least but not in the electronics field. Did you know that the human body weighs 40 times more than the brain. Does that make fat people more intelligent?

Seagoing Personnel


First of all, note that we have dedicated a sub-forum dedidicated solely to Safmarine, found on our forum pages. Please be so kind as to make a visit and leave your mark. We welcome your stories and you can upload pictures as well. You may ask why we have added a forum of the navy into our pages well the answer is simple – they transport parts, they need parts and this is also a community network. I don’t find many pages dedicated to ex or current mariners that want to communicate with each other on the net besides possibly Face Book.  In time we want to incorporate a sub onto this website dedicated solely to the navies throughout the world. Time has flown, just like the time flies on modern ships which no longer spend lengthy stretches in port where sailors get up to all sorts of tricks and pick up unmentionable diseases. My first ship was the S.A. Morgenster and my last the S.A. Waterberg, in September 1988. I was the most talented radio officer on board – mainly because they only had one.  There are numerous websites dedicated to morse code/CW transmission. is one. 

In order for me to compile a log of all the seafairers that travelled our oceans as a Safmariner please register on this website – you can use your FB or Twitter details as well and drop me a line through  Depending on the authenticity and interest I will compile a fact sheet(vessels, people of interest etc) to go with the pages of  Of course I will be doing the same with all interested parties from other shipping lines as well as the defence force. This is an international network so I really don’t have any qualms in making up pages of content as we go along – but in time this will be automated. I want to add an extra mySql database to our host site to control the input. What am I getting at?  Well for starters my intention is to allow subscribers to add a shipping line, vessel, registration details, service details, date and crew member.  Also, intentionally if a seafairer requires assistance in some manner away from his home port he can also use our pages to look up a service provider. Just look for instance at the issue of having a faulty laptop and the user needs it attended to. Parts-Ring subscriber network will provide the user a look-up facility.  Right now, in South Africa, if a tourist visiting for the FIFA world cup requires technical assistance in some manner our pages would help. Have you ever tried to get assistance through the Yellow Pages. In my real job I only use the Yellow Pages but it’s a bind. A lot of companies advertising only have a cellular number – I drop those like a red hot poker because of the lack of address details.  I’m sure everybody at some stage or other travelling overseas has been conned by some unscrupulous land-lubbing service agent. I recall an incident where a service engineer for Decca radar in Marseilles had to keep going ashore to get more spares and each time he came back he was more pissed. Eventually we had to escort him off the ship. And we still got billed for his time. 

Thank you for your time and hope you come back soon.

Subscriber Services

 and replaced it with a downbeat version of the original.  Readers become subscribers (for free), subscribers post spares, parts and services. Readers can search for a specific service provider in their area and request their services.  We have left out details regarding hours of service – email the provider or agent for these details.  It’s assumed, hopefully correctly, that persons looking for a particular service would be in the same time zone as the provider Wink.

We ned to emphasise to all subscribers that your details become publicly available – I for one hate phone a cell number requesting a service when there is the possibility in the near future that we can’t get back up service at a later date.  Do let us know when a service is excellent and/or horrific.  However, this site is not for finger-pointers and cranks. We need legitimite mails, aimed at making either the provider aware of an issue or when you have been seriously happy with the performance of an individual or company let us know – we will post their company details as an advertorial for free on these pages. Reputable business will have access to these pages as moderators and editors. We want your business to be a success as much as you. Initially we had a scrap pad for subscribers but in order for us to promote our bulletin board we would prefer you to go this route.

Tired of the old garbage? Let us know so we can make the necessary changes.
Need more functions? Let us know so we can add these in too. Cool
What is important is that users, readers and subscribers use our site as a look up tool. We are going to allow for the posting of schematics as well. Remember that we supply a free service and need you to also click on Goodle banner ads to generate revenue for us. 

I hope you find our site useful and pass on the information to friends and family.

And hey! go there now…

Yours sincerely
The Website Team