Radios for SAR Page

Icom F50 Handheld Radio
We have been using these little radios in the field since 2006. Although they are small in size they are by no means lite on features.
Some of the things we really like about the F50:

• They are small and light
• They put out 5 Watts - provided you use the rechargeable batteries
• They are easy to use
• They are waterproof and yes we have tested this many times
• They do Live Tracking - just add a GPS speaker/mic
• They are reliable - the only part that lets them down is the battery
• They have some rather advanced features like txt messaging
• They display an ID of the calling station. Really handy when people are accidentally pressing the PTT button
  
  We even can send txt messages to one or more radios from Base. The orange button has been reprogrammed to allow the user to scroll through the messages.
  
  We can also poll the radio from base for its GPS location. This is a silent message that gets sent to the radio which immediately responds with its GPS string.
  
  With the GPS Mic attached we get about 12 hours use per battery. Provided each team carries a spare battery we find that 12 hours is adequate.
  
  A speaker/mic is always used with these radios. This is mainly to reduce the chance of them getting lost.
  When in the field a Floppy Jim type aerial is always used as well.
  
  New Features When purchasing an F50 it appears that the F50V (V for Vibrate) is the lowest featured version available. Also the vibrate facility, like the voice recording, is best suited when you are setting up calls to specific radios. We have no need for these features as in SAR we expect the radios to be monitored at all times.

Icom F5063 Base Radio
The F5063 is built as a mobile radio but it works really well as a Base radio. The F5063 is the 25 watt version for the 50 watt F5061 sold elsewhere. We like the way this radio has features that are almost identical to the F50. The most important feature being the BIIS.
Some of the things we like about the F5063:

• It is compact
• It has an excellent range of features
• The BIIS data is available via the RS232 port on the back of the radio - no special cable required
• It has a speaker built in
• It is simple to operate
• It has better sensitivity and transmit power than the F50s we have been using at base
  

We needed a power supply to power the F5063 from the 240V mains supply. We purchased a power supply/charger unit from Wellforces model PB-120N-13C, 120Watt, 13.8Volt by Meanwell. This is reasonably priced ( less than $100 ) and relatively small. It does have a noisy fan although it appears that it has capacity to spare and if the fan is disconnected it will not overheat and shut down.

At some stage we will investigate options for a small UPS to deal to the power outages that occur when we are swapping batteries on the inverter. We know this will be tricky as many UPS devices do not like the square wave output of our inverter.

Floppy Jim Aerials
Over the years the YSAR members have learned the value of the Floppy Jim Aerials. They have also learned that they have a tendency to break. During a typical camp we were breaking 4 to 6 of them.

Most of the breakages were due to rust. A small amount of moisture finding its way through the heatshrink would rapidly start the rusting process. Then the tape would break at the weakest bend point.

Consequently we set about designing a new improved version but using the same principles. In fact we started by modifying the Floppy Jims as they broke. The key to the change is to replace the steel measuring tape with coax shield and piano wire inside thick-walled air tube.

More details to follow.