Monday, May 28, 2007

35Mhz -- update from Dave Armitage

Hi All,
Just a further update on the Four Wheel Drive Club problem we are experiencing. ICASA are becoming a lot more communicative at present. They are talking to the Four Wheel Drive Club and are intent on migrating them up into the 39 MHz band. This will take time but I have been assured again that the licences issued for their 35 MHz activity will not be re-issed when they expire in December. I have not had a reaction from the 4WDC as yet, but I expect to talk to them during the coming week. I have however spoken to one of the Senior Managers there and he is horrified as to what has happened. He has also initiated an investigation to ascertain if any other "users" might have slipped through the net on 35 MHz.
Dave Armitage

Friday, May 25, 2007

Radio Frequencies: what happened? -- Piet le Roux

At this stage our the 35MHz band, is unreliable because it is also being used illegally by two- way radio channels which were issued by the old Department of Communications. The 53.3 to 53.9 MHz band (channel 31 to 43) has just disappeared without anyone noticing it!

In 1997 the old Department of Communication started to implement project SABRE, this mainly impacted on the 60 MHz users and they had to be migrated. Foot note 3.32 in this report said the following:
South Africa currently uses the frequency band 60.1375 - 60.375 MHz for the control of model aircraft, which differs from bands used elsewhere in the world. In order to allow the model aircraft community to benefit from international economies of scale, to facilitate international competitions, etc, it is proposed that the model aircraft control band will be moved to be in line with the European band at 35 - 35.25 MHz.

The existing model aircraft control band could be released in the medium term. It should be noted that the new band will not be available immediately for use for model aircraft control, as existing users will need to be migrated out.”

So it acknowledged that there were users between 35 and 35.25 MHz and that they had to be moved but it makes no provision for the users between 35.25 to 35.5 MHz because at this stage they wanted our band to be the same as Europe (35 to 35.25)

But there were two 60 MHz bands 60.1375 to 60.375 (for aircraft) and 60.025 to 60.125 MHz (for model control).We were given 35 to 35.25 for the 60.1375 to 60.375 band but after 2000 when ICASA took over, they realized that they needed the whole 60 MHz band, so the gave us 35.25 to 35.5 MHz for the 60.025 to 60.125 band .But 60.025 to 60.125 was for model control, meaning everyone, so the 35.25 to 35.5 should have been for general use. This was done without checking that the users on 35 to 35.25 had been migrated and without making any provision to migrate the users on 35.25 to 35.5 MHz. At the end the whole 35 to 35 .5 MHZ band were given to model aircraft control. This was not a well thought thru plan because such a big band will cause problems with receivers using a 455 KHz intermediate frequency.

ON the 24th of March 2004 all changes were published in the government gazette and became law. For some unknown reason the 53.3 to 53.9 MHz band were not published in the government gazette. It looks to me like they just forgot because nowhere in any document is it mentioned that that band would be taken away. Nevertheless they way that the South African Table of Frequency Allocations reads at this time is that 50 to 54 MHz is for ham radio use and they would share 53 to 54 MHz with Wireless microphone use. The only 50 MHz frequency for model control is 54.45 to 54.55 MHz. If you want to use 53.3 to 53.9 you would have to get a class A radio amateur license.

The Two-way radios currently using 35 to 35.5 MHz can not be simply moved to above 35.5 MHz because that band is reserved for the base station leg of a repeater setup. The nearest single frequency mobile bands available are 33.25 to 33.5 MHz or 36.825 - 38.5 MHz. The 36 to 38 MHz band is the nearest but is mostly still used by the government.

Safe Flying

Piet Le Roux

Monday, May 21, 2007

Use of 35Mhz by Four Wheel Drive Club -- update from Dave Armitage

I have been watching the various postings etc to do with this topic and I must say that some inputs are sensible, Others are really living on cloud nine, however, the situation at present is as follows. We have discovered that the 4 wheel drive club are licenced by ICASA to use 35.225, 35.250 and 35.300MHz. The licences go back to 1989 and the 4 wheel drive club pay annually to be able to use those frequencies.
They use 35.225 for normal day to day communications during the times they are rallying or racing. They also use it to communicate when marshalling the competitions. They could also use it on there way to and from a competition. The 35.250 spot is used as a standby if 35.225 is cluttered. 35.300 is used purely as a distress, emergency or medical request frequency. Why ICASA have let these slip through the net is anybody's guess, but it has happened and at present we must live with it until these guys are migrated off. I have spoken many times to ICASA trying to sort this hassle out, but now I am getting reports from them that many other people have also had a go at them telephonically, some very abusively, and it is not HELPING OUR CAUSE. Please guys do not do it.
I have also spoken to the 4 wheel Drive club also. They are being very amicable and will change frequencies if we can get ICASA to allow it. From what I understand from their radio guy, it is just a question of re-programming the on board E-Proms. This they will do quickly if it is sanctioned by ICASA. They have also promised to cut down any idle chatter on those frequencies.
We have therefore formulated a proposal to ICASA that they allow the 4 wheel drive club to operate above 35.600 MHz. Since presenting the proposal ICASA have gone a bit quiet and are difficult to communicate with. I suspect much of this is due to other members also trying to get through and attack them. Our next tack is to go up the chain to the senior managers and arrange a meeting with him during the coming week. In the meantime the recommendations not to use 35.220,35.230, 35.250 and 35.300 are still in force.
The 4 wheel drive club's next competition is to take place from the 12th-18th June, but is will be in Botswana. Well away from us but that is not to say they will be using either of their first two channels to communicate whilst on route or return.
There have also been reports of interference on 35.140 and 35.150MHz.
I have forwarded what reports I have but as yet I have nothing to substantiate them.

Dave Armitage

Wednesday, May 16, 2007

Barnstormers Heli Fun Day

More info here.

2007 Gauteng Heli champs entry form

Entry form here.

Robertson Fly In -- Wessie

Hi all

It seems that the excitement over the Robertson Fly-in is getting to fever pitch. I have had reports that people are coming from all corners of the country! Looks like its going to be a sell-out.

Just a last few things :

1. Remember, its the weekend after next, so maiden what needs to be maidened, and charge all those batteries!

2. Looks like quite a few flyers and families will be tent-camping tarmac-side. There should be a good campfire vibe there and lots of company.

3. The Event IS a SAMAA endorsed fly-in, so SAMAA membership will be compulsory. No Exceptions. Please make sure you have your SAMAA card with you. Full TX and frequency control will be used throughout the weekend. Please label your tx with your name.

4. Please let the organisers know by means of email or phonecall that you are coming, so that they can prepare for the numbers. (Contact details below).

5. I have attached a list of B&B's and guest houses in Robertson if camping is not your thing. Book now to avoid disappointment.

6. There will be stalls representing the local hobby shops, and we will try to bring some spares for those last minute repairs or minor mishaps, some kits and perhaps something small for the little ones. Please drop us an email ASAP if you want us to bring something specific. Remember to bring some dosh and plastic!

7. There will be plenty of food and drinks on sale, as well as braai-packs, potjiekos and breakfast will be available on Sunday morning. There will be a cash bar on the Saturday night.

We hope to see you there, please stop by the Clowns Hobbies stall and come say howzit!


RMFC Contact Details :

Morne Swanepoel :




Friday, May 11, 2007

35Mhz interference -- update from the noble Armitage

Hi Guys.
I am surprised at the reaction of some people wanting to go back to the dark ages of 60 Mhz and no this is not a plot to make pilots buy the new 2.4Ghz equipment. This is a serious threat and is being treated as such.
The truth of the matter is as follows.
I have received numerous verbal accounts of pilots at a few sites claiming to have been hit by interference. Only a few of the less vocal pilots have bothered to put pen to paper and give me the facts on the official Incident Report Form that can be downloaded from the SAMAA website. Those pilots who have bothered have had their reports directed to ICASA immediately.
The new threat from The Four Wheel Drive Club has only surfaced this week and again it was passed directly to ICASA with a strong request as to why this could be happening after the Aeromodelling community has been allocated the band from 35.000 Mhz to 35.500Mhz.
I understand ICASA were as surprised as we were but it would seem the original licences were issued in 1986, long before the band was allocated to us and these odd ones may have slipped through the cracks as far as they are concerned (though they do not admit it).
The licences are due to expire in December 2007 and will not be renewed. In the meantime ICASA are busy migrating these users off the frequencies they are using on the 35 Mhz band. I have this in black and white from ICASA.
I would therefore recommend as a safety feature that until we have an assurance from ICASA that these users are definitely off our band we should not use the following frequencies. 35.220, 35.230, 35.250, 35.300,. I am not sure about the 35.325 spot they may be using. I am still awaiting clarification from ICASA about that but if it is true and the 4 x 4 guys are using it then 35.320 and 35.330 spots should also be avoided.
I will update everyone when I have more information
Dave Armitage

Thursday, May 10, 2007

Possible interference on 35Mhz band

There is some evidence of interference on the 35mhz band near the MMS site in Midrand.
(More details on the MGASA Yahoo group.)
There is no suggestion that this is happening anywhere else.

Here's a briefing note from Lionel Brink:

Hi Everyone

I have just spoken to Dave Armitage (SAMAA Technical Committee) regarding the possibility that certain 35 mhz frequencies may be in use for purposes other than radio control flying model aircraft.

Please be advised that all the relevant documentation was immediately forwarded to ICASA & every attempt is being made to obtain a prompt response. I am appealing to everyone to provide SAMAA & Dave with the time to deal with this matter through the appropriate channels. I have been assured that we will be updated with any relevant information as soon as it becomes available.

From a flight safety perspective, pending further notice, I recommend reconsidering use of these potentially affected frequencies for any form of RC flying. I understand that the potentially affected frequencies are 35.225 mhz, 35.250 mhz (slot 85), 35.275 mhz and 35.300 mhz (slot 90).


Lionel Brink

Friday, May 04, 2007

Percy on Money and Control Line Flying

Hi to all those who fly control line or who would like to fly.

Before I get to the money part please note that May 19 is a Barnstormers club flying day for the control line section.

Flying starts at 10 and will end late. As usual on club flying days a braai fire will be provided, bring your meat, eats and cold drinks and join us.

We especially invite juniors, those who would like to try and those who used to fly control line to join us for some fun on this day, 19 May.

Now the money part.

The Control Line SIG has received an anonymous donation of R3,200. The donation states that R2,200 must be presented to the juniors (defined as any one 18 years or younger) that fly at the next Control Line Nats. The donor recommends that the money be awarded as R1,000 for first place, R600 for second, R400 for third and R200 for fourth place but will consider alternative suggestions from the SIG Committee.

The Nats will be held during the school holidays in April next year, possibly at Barnstormers. This should help those who has to travel far so that they do not need to miss any school days.

The SIG will arrange accommodation for those who need it.

If you will be 18 years or younger (e.g. not yet 19) in April 2008 you can earn money by starting to practise your control line skills now.

Should you know of someone who may qualify for the prize money by April next year , please forward this to them.

If you need help with models, engines, lines or anything else related to Control Line contact Keith Renecle at 083 415 1409 or Percy Attfield at 082 556 9147.

Start your control line career at the Barnstormers open day May 19.

The other R1,000 is to go towards the expenses incurred by Keith Renecle during his overseas trip to lead a Control Line Aerobatics judges workshop during June.

Percy Attfield
Control line SIG Chairman

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