[Elecraft] KX3 Batttery life question...

[Wayne Burdick]

To each his own, but....

Mike Morrow wrote:

> In the 45 years I've been around ham radio, the probability that any  
> HF
> ham rig would be used in an emergency has been vanishingly small, with
> the highest probabilities having been 45 years ago, not today....

A few years ago a ham in Oregon broke his leg hiking. He used a KX1 to  
call rescuers. I'm not kidding.

VHF/UHF doesn't work at all in many mountainous areas, at least if  
you're down in a hole between peaks. For that matter, there are wide  
stretches of the West with no repeaters. NVIS on 40 m with a wire-in-a- 
tree or a backpacking dipole will often do the job with just a few  
watts.

The clincher is that the end of the world is coming (!). I heard this  
on a shortwave station, thanks to the KX3's general coverage receive.


> An emergency HF radio would, in any event, need to be resistent to  
> harm
> from adverse environmental conditions *while in operation*.

Around here the most likely emergency that would cut off  
communications is an earthquake. Small radios stored in bags are  
likely to survive and be quite useful. It's buildings that suffer.


> An emergency HF radio should also *not* be a QRP rig...at least no rig
> *designated* as an emergency radio.

I routinely check into a 40-m net and get good reports during the  
daytime with a short antenna 15' off the ground and 5 watts. HFpackers  
often running 10 W or less check into daily nets on 17 m and 20 m and  
work stations thousands of miles away. If there's a will, there's a  
way, and QRP will often get through. Even when it doesn't, it's fun  
trying.


> An emergency HF radio should also have sufficient battery capacity for
> more than just a few hours of intermittent operation.

Depends on what you mean by "intermittent." If my KX3 gives me 10  
hours of casual operation at 3 watts from a 2500-mAhr battery, surely  
I could maintain useful communications during an emergency by being  
even more judicious with my transmit time.

That said, a small, collapsable solar panel would be an excellent  
addition to the station. It can power the KX3's internal battery  
charger.


> On a *short* hike, carrying a 4 AH battery which prudence mandates  
> won't be
> much of an impediment.  I've done that many times, even when I used  
> SWL's
> small DSW-20, -30, and -40 units.

I travel *really* light. On day hikes my entire station weighs about  
1.5 to 2 lbs, allowing me to carry two cans of beer rather than one.


> On a long hike and overnight stay, a 4 AH battery will be mandatory,  
> unless
> one enjoys the dead weight of the KX3 and antenna after the internal  
> batteries
> are depleted.

5-10 hours of operation from a charged 2500 mA internal battery is  
sufficient for all but the most boring business trips or hikes. I'm  
usually hiking (or businessing) a lot more than hamming.

73,
Wayne
N6KR