Operating Portable and Activations

With all the fuss being made about operating on the freeband operators may be forced more and more to go underground and conceal their activities, somewhat like an activation in a country that is not CB friendly at all. If there are no local operators in a particular country then the chances are transmissions from that place are usually classed as illegal and can carry severe penalties with equipment confiscation a certainty if one is caught. In a lot of places it is difficult even to get equipment into the country without raising suspicions. Oddly enough in India you fly through customs with a wave on arrival but they search you thoroughly when you are leaving..They picked up my walkie talkies one time but since we were leaving let them go…Had to ask the boss first…and again in Brunei the magnum S-9 was discovered and questioned but not seized. It was a car radio and would be taken back out when I left and I had a booking 4 days later…Indonesian customs will make a fuss if they find any radio equipment (and they will hone in on heat sinks) No telcom permit and they may take it off you…

With this in mind I have been sorting out my equipment list for an activation is a country that frowns on unlicensed transmissions (Which is everywhere if you are on freeband) 
Criteria: Simple, lite weight, easy to deploy, 100w, omni antenna.

Radio: Small, Light, Good receive, 25w PEP OK, Cheap, can work Split, Doesn’t run hot. Not a Ham radio.
The only radio that really meets all of this is the Optima. The Optima audio can be listened to all day on headphones with out the white noise most of the newer radios generate.
Radios considered were the Stryker 955: Good output, Runs cool, heavy, can not work split on the fly (but can be programmed) Receive a bit noisy. Weight the big problem.
Cre 8900: Similar to the Stryker with reduced power but small and light and noisy receive. Size is the big plus.
Maxlog M8800: Similar to the cre in most respects but bigger. Cheap is the big plus. Audio is DX oriented..Sharp. Lighter and cheaper than Stryker and easier to use. Less power.
Optima: Comes out on top due to ease of use on freeband, Can work split from the front panel, Steps easily in 1khz, Has additional filter for noise reduction, receive does not tire user, and it has a fan on the heatsink. Its very light and simple to operate. Power output on SSB around 40W. 5 memories. Costs about the same as the cre, a bit less than the stryker and a lot more than the Maxlog. 
Most other CB radios I looked at could not work split so that ruled them out from the beginning.

Power supplies: 2ea 30A switch mode brick types from mean well in China. Lite, cheap and work well ! One for the radio and one for the Amplifier. 110/220v AC. Checked and don’t create hash on 11m.

Antennas: The choice of antenna is probably the hardest to make as the effectiveness of the antenna usually determines the effectiveness of the activation. Of course if there is no propagation on 11m when you are there all the power and big antenna won’t help much either. 

There is nothing free in this world and antenna gain is the same. Antenna gain comes at a price. An antenna does not manufacture any more energy than the radio puts in to it..the antenna merely concentrates it in a certain direction at the expense of other directions. Directional antennas such as Yagis and quads etc focus the radiation into a beam type pattern a bit like a torch. (Taken to extremes we have a parabola antenna…not much use on 11m DX.) My thoughts are that an activation needs to be able to hear and work from all directions all the time because one doesn’t usually know the propagation patterns for an area we are not used to operating in. Easy to miss an opening if the beam is facing the wrong way. And it may not be easy to keep turning the beam. A 5/8 wave vertical tends to concentrate the bulk of the radiation at a fairly low angle which is fine for long range ground wave and long range DX but loses gain on the shorter high angle skip paths. Possibly still the best Omni DX antenna option.

Beams: beams can be heavy, Not easy to transport complicated to errect and get into the air and are very visible. They also need to be rotated and may require guys. They will get you more contacts in the favoured direction but a lot more time is spend assembling and errecting that could be spent on air. On the other hand, if you are going to be at a single location for a couple of weeks the time and effort putting up a beam will pay off. The pile ups will be more hectic but the signals will be received a lot better and the ability to focus on a particular direction at the expense of all others is useful. Noise levels are usually lower than a vertical.

But I have decided against a beam. Just don’t have the time or the ability to get it up and in the clear and not draw undue attention to the activation.

Verticals. usually made of aluminium and 18-22′ long. Most commercial verticals have quite long segments that don’t travel too well…the Imax and A99 fibreglass antennas for example are 6′ long when packed for shipping. Not so heavy but still need a mast that can take the weight of them and get them out in the open. No antenna will work well on 11m in a tree or under a veranda or roof. But put a vertical on a tin roof and watch it sing. If you know you have access to a tin roof the vertical is the one to go for..even a 9ft mobile whip will work well mounted on a tin roof.

I have decided to go with a wire dipole made from a length of RG58…one end plugs into the radio and the other is the tip of the radiator…no joins. Simple to make, simple to tune, simple to put up. To erect it I will use a 31′ telescopic fibreglass pole that comes in 4′ sections. Pull the sections out and a little twist and they will hold together. No clamps. The wire dipole can be mounted in the middle as an inverted V and tied off to guy the mast or it can be mounted vertically with the lead and the braid side running down the side of the fibreglass. (Vertical dipole) Can be deployed like this in seconds sticking out anywhere it can be fastened. In Brunei it worked well with the base of the pole attached to the balcony out side the room on the 10th floor. Conditions were not good back then but the 40w was easily heard in europe. This time I will be able to get it much further away from the building. I have found with an antenna like this, once it is cut for resonance the swr will stay pretty constant and any changes will be due to the angle of the wires. need to keep the angle over 90 degrees.

Countries like Asia and the middle east where the dwellings have flat roofs are much easier to get an antenna up in the clear and out of the way. Places with high sloping roofs are the most difficult and without a balcony things quickly look bleak. 

Another option is operating mobile. If you have a mobile antenna and can hire a car you can situate yourself in a position favouring DX…either on a hill in the clear or down by the sea. In my experience down by the sea wins hands down over any hill top for skip. Best is on a jetty over the sea! But in a car you can drive up to a convenient high point in the clear and even a simple magmount antenna can take 100w PEP. No reason why you couldn’t take beams and verticals like we see our friends in the UK using but it must be a chore to have to stay in a car all day just to work some DX..

Amplifier: Something light and small, cheap, and about 150w should be ample. I have found some amps with 4 ERF 7530 mosfets that will put out 150w on the middle setting and draw about 20 amps when driven with 40w. Will need to add some fans as they do heat up after a while…They are rated for 300w pep when driven accordingly so they should be OK at 150w if required. Prefer not to use it. Even though most TV’s are digital these days and relatively unaffected by transmissions on 11m there is still the chance of coming through stereos, and other electrical equipment once one starts cranking up the power. Better low power and low profile…

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