On Thu, 26 Oct 2006 21:20:48 GMT, Jim - NN7K wrote:

Always wanted a 1 FARAD (or bigger) capacitor!
Where can you buy one?? (Short of buying a
"Charged "one, I.E. Storage Battery)? Oh
well only 6 Months to April First!

Hi Jim,

1 FARAD (or bigger) capacitors have been around for YEARS. Go to any
Hi-Fi shop and spend as much as you want. Be warned that cost is
proportional to breakdown voltage rating.

Or try:
http://www.hobbyengineering.com/Sect...tml#CatPSSUPER

73's
Richard Clark, KB7QHC

On Thu, 26 Oct 2006 15:02:55 -0700, Richard Clark
wrote:

Or try:
http://www.hobbyengineering.com/Sect...tml#CatPSSUPER

Or for up to 50F for less than 50 Cents a Farad:

http://www.newark.com/NewarkWebComme...comSearch=true

Interesting to note this one of the few, practical (meaning making
money in a commercial market) Nanotech applications of an aerogel.

73's
Richard Clark, KB7QHC

Jim - NN7K wrote in QE90h.22140$e66.18599
@newssvr13.news.prodigy.com:

Always wanted a 1 FARAD (or bigger) capacitor!
Where can you buy one??

Try your local car stereo place. About the size of a tennis ball can.
Best Buy has some on their website. Search for capacitor.

--
David
KR7DH

Jim - NN7K wrote:
Always wanted a 1 FARAD (or bigger) capacitor!
Where can you buy one?? (Short of buying a
"Charged "one, I.E. Storage Battery)? Oh
well only 6 Months to April First!
Jim NN7K


Richard Clark wrote:



Not unless you can assemble a couple hundred Farads (note the complete
absence of pico, nano, or micro in that Farads). The short version is
DON'T GO THERE.

73's
Richard Clark, KB7QHC

Why settle for a measly 1 F when you can have 50 F?

Go to www.digikey.com and search for 283-2511-ND.

--
Jim Pennino

Remove .spam.sux to reply.

wrote:
Jim - NN7K wrote:
Always wanted a 1 FARAD (or bigger) capacitor!
Where can you buy one?? (Short of buying a
"Charged "one, I.E. Storage Battery)? Oh
well only 6 Months to April First!
Jim NN7K


Richard Clark wrote:



Not unless you can assemble a couple hundred Farads (note the complete
absence of pico, nano, or micro in that Farads). The short version is
DON'T GO THERE.

73's
Richard Clark, KB7QHC

Why settle for a measly 1 F when you can have 50 F?

Go to www.digikey.com and search for 283-2511-ND.

--
Jim Pennino

Remove .spam.sux to reply.

And if the 5W output rig draws an amp on transmit, that 50F cap will
run it for 50 seconds with a one-volt drop. Compare that with an
inexpensive little 7Ah 12V gel-cell battery that will run it for
probably five hours. Caps may make sense to smooth over short pulses
of current, but seem like a poor solution for storing long-term energy.

The OP's question is so basic that I wonder if he's pulling our
collective legs.
--How many amps does the rig draw in transmit? In receive?
--How long do you want the aux power source to run it?
----how many hours of transmit; how many hours of receive?
--That tells you the minimum Ah rating for the aux battery.
--Use I = C * dV/dt and how much voltage drop you can stand
to figure the size capacitor you'd need to do the same thing
for an aux capacitor (and then discard the idea in favor of a
much cheaper battery).

Cheers,
Tom

Jim - NN7K wrote:

Always wanted a 1 FARAD (or bigger) capacitor!
Where can you buy one?? (Short of buying a
"Charged "one, I.E. Storage Battery)? Oh
well only 6 Months to April First!
Jim NN7K


Check with your local high power car audio shop. They carry them.

I have one, but it's only half a farad at 30 volts.

tom
K0TAR

Richard Clark wrote:

Hi Myles,

Fuel Cell??? That is a pretty pricey option.

More than likely it is 100WH (Watt-hour, not Watt) rated.

https://jadoopower.com/fuel_cell.html

On Thu, 26 Oct 2006 08:53:31 -0700, Jim Kelley
wrote:



Richard Clark wrote:

Hi Myles,

Fuel Cell??? That is a pretty pricey option.

More than likely it is 100WH (Watt-hour, not Watt) rated.

https://jadoopower.com/fuel_cell.html

Which reports:
Output: 12 VDC Nominal
Wattage: 100 W Continuous

WOW! Infinite Watt Hours. I think we can walk away from the mid-east
right now.

Richard Clark wrote:
On Thu, 26 Oct 2006 08:53:31 -0700, Jim Kelley
wrote:

Richard Clark wrote:


Hi Myles,

Fuel Cell??? That is a pretty pricey option.

More than likely it is 100WH (Watt-hour, not Watt) rated.

https://jadoopower.com/fuel_cell.html


Which reports:
Output: 12 VDC Nominal
Wattage: 100 W Continuous

So apparently your correspondent was correct after all.

WOW! Infinite Watt Hours. I think we can walk away from the mid-east
right now.

No, actually when you take time to understand the literature (like
Myles evidently has), it becomes quite clear that the limit to the
rate at which energy can be extracted from the power unit is 100
watts, and that the total amount of energy which can be extracted is
determined by the capacity of the fuel cannister; either 130
watt-hours or 360 watt-hours.

So it seems that if you want to be able to rely on this power source
for any extended length of time, 5 watts would not be an unreasonable
load. I'll wager it would even count for 100 extra points at Field
Day - albeit at a cost of $15-$20 a point.

73, Jim AC6XG

On Thu, 26 Oct 2006 08:53:31 -0700, Jim Kelley
wrote:

Fuel Cell??? That is a pretty pricey option.

More than likely it is 100WH (Watt-hour, not Watt) rated.

https://jadoopower.com/fuel_cell.html

Very interesting.

But

Seems like those fuel canisters are just a bit on the pricey side.
And what fuel do they indeed use? Complete lack of info on that.

I see the website mentions refill stations. What kind of power do
those use? How do they work.

Tony