Typhoon Milenyo - September 2006

Were you prepared for the long blackout which occurred during and after Typhoon Milenyo struck? There is no excuse for not knowing the possible consequences as this has happened many times in the past. People do tend to forget. The last time a strong typhoon struck Metro Manila directly was in 1995 so perhaps there is some excuse. Other provinces have had more frequent typhoon strikes and Bicol was particularly badly hit this time.
Most people in Manila had two days of blackout, with consequent lack of water as well. Many power lines were brought down and MERALCO worked overtime to clear up the mess and restore power. The whole of Luzon was blacked out as damage forced various grids to shut down. Large advertising billboards in Manila were blown down causing traffic chaos as well as deaths in a few cases. Thousands of felled trees also caused traffic hazards and injuries, and flooding due to the heavy rains was widespread in low lying areas.

 

PAGASA gave frequent warnings on their website and these warnings were also displayed on our PARA website starting about three days before the typhoon hit. The PAGASA information is shown on the PARA news page with a note on the main page directing viewers to the information. Unfortunately the updating can be disrupted because of power outages!

The information from PAGASA is updated 4 times a day, at 5am, 11am, 5pm and 11pm. There are also other websites which show satellite pictures on an hourly basis and these pictures can be combined to make an interesting movie showing the actual track of the storm.

 

 

 

How did your radio station fare in the midst of all this? As Filipinos we should all be aware and prepared for the ravages of typhoons every rainy season, but how many of us really are? What do we need to maintain our ham stations on the air in case we are needed to provide emergency communications?

Power supplies are, of course, a priority as without power our ham radios are just useless. For those without generators, 12v batteries are the norm. You should ensure all your standby batteries are fully charged before any possibility of blackout conditions arises. Keep an ample supply of low voltage batteries for flashlights and make sure emergency lights are fully charged. Be aware that the sealed cells in those lights might not be fully up to spec if the light is more than a year or so old so check the battery capacity by seeing how long it takes to discharge when normal conditions prevail. Spare batteries for these lights are readily available and you should have spares for the actual lamps themselves, whether they are fluorescent type or incandescent bulbs.
If you are using deep cycle or general purpose car type 12V batteries, make sure you charge them in an open area to avoid accumulations of hydrogen gas which is flammable. A single spark can cause an explosion. Deep cycle 12v batteries are excellent for use with inverters which can supply 220vac for equipment which needs it, such as laptop computers and cell phone chargers for example.
Small 12v sealed gel cell type batteries are ideal to run small receivers which can be used to monitor local radio stations for disaster news. DZMM on 630kHz is a favorite with many people here in Manila as they concentrate on what is happening to mains power producers such as NAPOCOR and MERALCO. Usually the MERALCO hotlines are swamped and it is best to listen to your local AM radio station for the latest news.

Solar cells, though expensive at present, are very useful for recharging batteries of all kinds. Even sunlight diffused through clouds will give an adequate charging current to keep your battery life extended.
220VAC generators are the best solution but are expensive to buy and run. They produce noise and must be run outdoors to prevent exhaust fumes from being a hazard. They can, however, produce enough power to run your ham gear as well as house lighting and other requirements such as refrigeration and water pumps.
Lighting needs can be met simply by the use of candles but care should be taken and they should not be left unattended. Many fires are caused during blackouts by fallen candles.
Battery operated lamps are safest but may not last very long unless you have an ample stock of replacement batteries. Gas power lamps can give large amounts of light, but again, they should not be left unattended in case of problems.

Cellular phones are ubiquitous these days. Do you have a spare battery for yours? Most people don't expect brownouts to last very long, a few hours at most, but can you cope with loss of power for a few days? Your cell phone battery will be long dead before the power comes back unless you have some means of recharging it or you have kept a spare battery fully charged. In extreme cases, people have been saved by the use of cell phones when they have been trapped in collapsed buildings.

We must not forget our antennas. Did yours survive Milenyo's fury? Most HF Yagis are designed to withstand high winds but perhaps your mounting hardware or tower is not as generously rated. What use is your antenna if it is lying on the ground crushed beneath the collapsed tower? Check all your guy ropes and wires to make sure they are fit for the job. Polypropylene ropes can be damaged by sunlight and snap at low tension. Make sure your fixings are in good condition before the onset of the rainy season each year. Check all the bolts and clamps on the antenna system for corrosion or failure. Stainless fittings are good but you should check regularly that all the nuts are tight. If your tower is telescopic then so much the better as you should lower the antennas to a safer height and tie them down securely to avoid too much flapping of the elements.

If your antenna is supported by trees, for example a wire dipole held up between coconut trees, make sure the fixing ropes have enough flexure in them to avoid being snapped when the trees bend during high winds. Ropes with counterweights on pulleys are ideal when lots of flexing of trees is expected. Ensure the feeder cables do not flap about excessively.
Keep some spare wire antennas on hand so that you can quickly put up a wire dipole. 40m is the best band for inter-DU communications and the dipole can provide good communications between neighboring provinces. A loaded wire vertical will also work well but is more hassle to set up and tune compared to a dipole.

The internet is a good resource also but less reliable as modems will need alternate power supplies and phone lines may be down.
Local repeaters on 2m and 70cm are very useful and should have alternate power sources available to ensure continuity of service.
Finally, lightning strikes are common during storms so make sure your antennas are disconnected when there is a thunderstorm around. This is good advice for all year round anyway. You should also use spark gap arrestors in case of high voltage buildup on your antennas but there is no substitute for disconnecting your antennas completely. You should also disconnect phones and other items connected to outside lines when there is lightning around. Even a strike to the ground 100m or more away can cause damage in your home with very high voltages being induced on power lines, phone lines and antennas and rotator cables.

How did your station survive? Do you have any stories from the dark days after Milenyo, or pictures of your mangled antennas which could be an object lesson for others? Do send them in to us and we will publish them.
Any other ideas for disaster preparedness? Please send them in and I will add them to this article.



Good luck in the next storm, there will always be another one!


George
DU1GM

 

 

Philippine Amateur Radio Association, Inc. 2006-2008