preop/ ans calculations/ fuel cell battery buffer or cap?
In article ,
Tom Ring wrote:
ml wrote:
omitted) it's quite meets
code, very small, very light dosn't pollute or stink
seemed rather sexy the jado can also be powered from small cartridges
making the unit selfcontained and very portable, however this isn't a
requirement of mine but cool benni
the only con for me, seems to be a)not totally going to give me 100w
at full load b) i wish the unit was more than a puny 100w the larger
units i would have to pay full list for and are therefore outta reach
so solath and experiment
Ok, I have applied a simple power budget to what you stated your
original desire was, as opposed to your cut down 2m 5W system.
Using a rig I own, an FT-897, on HF.
Assume 90% receive at 1 amp.
Assume 10% transmit at 15 amps with 100 watts output, (measured as
opposed to the 22 amps claimed in the docs)
This gives 2.4 amps average consumption. (Check my math, the doctor did
a lot during my pre-op today)
1 week is 168 hours which gives us 403 ampere hours.
100AH deep cycle batteries are around 100 each (or less), So that's
about $400 for all the batteries you need for a week without sleep.
A modern top of the line charger, such as produced by Schumacher, is
less than $100, does automatic desulfation, will charge at 50 amps or
greater, and weighs about 6 pounds.
So now we are at under 500 dollars for an emergency power for any ham
that needs to run an HF rig for a whole week.
I just don't see why you want to use the fuel cell, it makes no sense.
tom
K0TAR
tom, am i to understand you had some surgery today? if so, i hope all is
well with you and taking the time to write is appreciated
i am guessing roy's calculation of the total ampre hrs needed is closer
to being correct, but it's 5am and i kinda don't know how to calculate
that so i dunno as stated in my earlier post i don't have the formulas
so i can't act to confirm but i nod my head and presume it's all correct
based on roys math
you are correct about what the rig is doing mine is exactly simular i
would calculate based on 20amps
re your last comments on why i would want a fuel cell, it should be very
clear in all my many posts
5480 watt-hours of battery is more $$ and large than i have practical
room for
i can get the fuel cell for practically nothing and i just thought it
might be able to offer some useful power to top off a battery to
provide some b/u power why not? and also be a fun experiment it runs
quiet , clean and i can get all the fuel i want free always, i would
never be able to get fossel fuels in a blackout or other emerg
so now i inch a drop closer knowing how many what hours my original
abandoned goal would draw , however my current stated goal is to just
power my 5w tx output(draws4amps) 2m mobile rig
and try to calculate how much the battery would be drained in a 1min
tx and then see if the 12v 7amps comming out of the jado would recharge
it fast enough i believe that is what must be calculated for just not
sure how do it, unless you still say a 7amp battery is still 'ok'
my goal was to be able to calculate
so a 7amp battery(or what ever is needed optically this seems like a too
low a #)) w/a 1min 4amp load would be ??%drained
then based on manuf spec's for the battery we could calculate how much
power &time would be needed to top it back off
then it would be simple enough to see if the output of the jado is
sufficient i think thats all thats needed i think that's simple
but i dunno how to calculate it
thanks all i really wanted to do
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