Other SAR Technologies

Battery Chargers for AA NiMH
We use heaps of NiMH AA batteries and a few AAAs. These are mostly for the GPSs and LED head torches. After much research into chargers we have settled on one which is expensive but very good.

This is the Uniross Sprint model AAB03147. It cost around $130 from Harvey Normans.
The cheaper chargers mostly base their charging on time or voltage and treat multiple cells as a single unit. Thus one battery may become severely overcharged while the other is not completed. The Uniross is clever enough to do the job properly and shuts itself down completely when each individual cell is completely charged. It can charge 4 batteries at a time. It charges most batteries from flat in 15 minutes. Well worth the money if you rely on your NiMH AAs
This model has since been replaced with a unit with similar specs but without the LCD screen. Make sure you get the Uniross Sprint 15 minute charger. The key feature of these chargers is that each cell is charged independently. This is critical for the optimum performance and life of the batteries.
The downsides of this charger are the high cost and the noise of the fan. The good thing about the noisy fan is that it tells you by turning off (going quiet) when all of the batteries are 100% charged. The 15 minute charge time is only to 80% of charge.

Maha MH-C9000 NiMH Charger & Analyzer
I recently acquired one of these charger/analyzer devices. It will tell you the actual capacity of your old batteries and will revive batteries that have less than their original capacity. At only $101 from Ian at Ecobatteries it represents really good value - it does heaps more than the Uniross at a similar cost. The downside is that a full "Break-in" cycle for reviving batteries takes two full days but the benefits are worth waiting for. If you have heaps of NiMH AA and AAA batteries then go and order one of these chargers today.

 

Laminated Maps
YSAR members occasionally lose their laminated maps when making their way through the thick Supplejack in our bush. We have looked at the option of printing maps onto plasticised paper with a laser printer so they could be folded and carried in a pocket. Then we realised they would still lose them.
The answer - we punch holes in two corners of the laminated map and attach a string which connects to the sternum strap on their packs . Sometimes it takes a long time to figure out the simplest solutions.

Generators
We (the Hamilton SAR Group) has owned a Honda generator for 6 or 7 years. The EU3000 is able to put out a good 3KWatt but most the time it only idles while powering a few lights and the computers. It also boils water in a standard electric jug or powers a waterblaster without breaking into a sweat.
The key features of this generator:

1. It is cheap to run as it adjusts the revs to suit the load. This really reduces the fuel consumption. We can do a whole weekend on about 15 litres of petrol. That's about 28 hours.
2. It is extremely quiet . This means that you do not need huge lengths of power cable to get the generator out of ear shot while at the same time creating a significant voltage drop.
3. It produces the 230V via an inverter so it is really clean and electronic friendly.
4. The electric start makes it really easy to get going even on cold mornings.

As with most generators we have trouble running some types of UPS devices on it.

LED Torches
The LED Torches have made a huge different to the amount of light that a team can carry for night searching. Also the reliability of LED lights is way better than the incandescent and Halogen lights that would blow bulbs after typically 30 to 100 hours of use.
Key factors that we look for when buying an LED head lamp:

• It must be a headlamp
• It must be light and robust
• It must run off two or three AA cells - not AAAs
• It should have a variety of brightness settings so that it can be dimmed to conserve batteries for close up work
• It must have a headband around the head and another over the top to keep it up
• It is good to have a small flashing multi-coloured LED to help locate it in the dark as well as indicating battery condition
• It must run on NiMH cells
• It must be at least one watt

My preferred headlamp is the Led lenser H7. This is a 3 Watter that has lots of good features at a reasonable price ($127 RR). Its downside is that it takes AAA batteries. However its features compensate for this.

We have recently laid our hands on a couple of small hand torches that have 3 watt LEDs. These put out an awesome amount of light. Our favourite is the LedTech torch that takes a single AA battery. I like the idea of having this tiny torch in my pocket as a backup and convenient alternative to the head-torch.

Network Switch/Hub

How do you get around the issue of maintaining a reliable computer network when operating off a generator? The weakest link is often the network switch. The laptops all keep running off their internal batteries but without a reliable switch the network is wasted. Some people use UPS devices to feed 230 volts to their switch but few UPSs like working off a generator.

Group member Bevan Holden solved the problem nicely by attaching the D-Link switch to a plastic box with a small 12 volt battery inside. The box gets connected to the 230 volt supply to keep the battery charged and the system can now withstand a generator outage of several hours.

Nice work Bevan.