[Elecraft] The Thoughts of Young Men

Fri Jan 17 09:26:01 2003

Hi

If you are speaking of a QRP K2 then a panel in the 5 to 10 watt range will
keep you on the air using the 2.9 amp hour internal battery or even better a
7 amp hour external battery. These batteries are used in small computer
backups and can be found surplus at reasonable prices. I have used a 5 watt
panel from Northern Tool (also Harbor Freight) with my controller and it
will do a nice job of keeping the battery charged. This panel sells for $69
sometimes on sale for $59

If you are talking about a K2/100 then you will need a little larger setup.
I used two 35 watt solarex panels charging a 35 amp hour gel cell battery
with my controller at field day this year. We were running the K2/100 at 100
watts most of the time on CW and SSB powered by this system and had no
problems keeping the battery charged during the day. We operated until
around midnight when I switched to a power supply to run the rig. The
battery was still ok but I did not want to take it down too far. The next
mourning the panels had the battery recharged in a few hours even though we
were operating the K2/100 from the solar setup at the same time. I did not
use the AC power supply to charge the battery at any time. If you were
willing to operate only a few hours per day and lower the power to 50 to 75
watts a 35 watt panel and a large 90-110 amp hour deep cycle battery could
power a K2/100 KAT100 rig totally from solar power. If you are wanting a
backup in case of power failure this would work also if you tie in your
station power supply to keep the battery charged and would automatically
switch to solar if the power failed.

My solar controller 2 Will handle up to 16 amps or about 200 watts max, way
more than you will need to run a K2/100. The solar panels get very expensive
when they are larger than 70-100 watts. Figure about $7-$9 per watt. The
controller kit is $35 and can be ordered from:

Don Brown
19132 Falls Creek Drive
Flint, Texas 75762

Includes the circuit board and all parts on the board instructions and
application notes on how to use with a K2 or K2/100

I also still have the noise generator kits for $15

Don Brown
KD5NDB

----- Original Message -----
From: <[email protected]>
To: <[email protected]>
Sent: Thursday, January 16, 2003 6:47 PM
Subject: [Elecraft] The Thoughts of Young Men

> In wintertime, the thoughts of young men (and women,
> maybe) turn to...
>
> SOLAR PANELS! (Yeah, right)
>
> Well, I'm not young anymore, but it is winter, and hard as it may be
> to believe, my thoughts have once again turned to solar panels.
> This past summer, I bought the "Dolphin Don" solar charge controller,
> the most affordable component in the chain of what was to be my
> ideal of a completely solar-powered HF/VHF station.  Regrettably,
> budget constraints have mandated a more modest goal.
>
> With that in mind, I ask: Based on your own personal experiences,
> what is the "best" solar panel out there that can keep the K2
> battery charged?  I'm looking for something of high quality and not
> necessarily portable that won't send me to Ham Heaven after hearing
> the price quote.  I'm obviously not looking for a panel or set of panels
> to sustain a large metropolitan city, just my K2.
>
> Thanks in advance for your input.
>
> 73,
>
> Bob  WA4FOM
>
> K2 # 2537 "B-upgraded and loving it"