Re: [tracker2] Re: T2-301 in a box
- You do want to allow for the cases where a team gets dropped off in BFE
and isn't able to get picked up because the helo's grounded by weather
or maintenance, or just has better things to do. I prefer to have
things run off of AAs for this reason, but frankly it's kind of a pain
changing out 8 of them in the field.
What I always found to be a bigger problem is battery shelf life. Too
much gear stashed away in bags for too long without being used. It gets
expensive replacing lithium (or even alkaline) primary cells after every
call, so they tend to stay in equipment longer than they should. NiMH
and NiCD rechargeables self-discharge way too fast off the charger, and
there are never enough chargers where you need them to cover both the
radios and the spares.
Li-ion and Li-poly batteries have a big advantage there in that the
self-discharge rate is low enough that they can be stored for long
periods without losing the majority of their charge. That's what I've
liked best about the PX-777 radios - my D7's batteries are NEVER charged
when I need it, and I can't store the spare anywhere but on the charger.
For the PX-777 I keep spares in ziplock bags and try to remember to
recharge them every 6 to 12 months, and they just work when I need them.
Tom Hayward wrote:
> > I would like to see a battery that will last several days, a switch
> on the
> > inside. No tinkering or confusion. 'Here is your tracker, its all set'.
> Just to be the contrarian...
> Every time I mention carrying another radio to my SAR team they ask
> "How much will it weigh?" I'd prefer the lighter 18 hour battery, with
> the option of a spare. Especially if spares only cost $45.
> If we do everything right, we rarely have a search that lasts longer
> than 18 hours. I would say, less than 5% of searches are over 18 hours
> (disclaimer: that's a guesstimate, not a statistic). I think covering
> 95% of cases without a spare is a good design goal--that's only my use
> case though. Your results may vary.
> Tom KD7LXL