I power my K3 from three sealed lead-acid batteries charged from
a solar panel. I have an inline fuse holder for automotive fuses
in the plus lead to each of the batteries. They have "OES"
stamped into the plastic covers.
If the fuse holders are warm to the touch, and there is not
other source of heat nearby, then you have your smoking gun and
that is where your problem lies. To trouble shoot this class of
problems, measure voltage drops through the power supply wiring
system. If there is a largish drop anywhere, find out why and
correct it.
I had to trouble shoot my battery setup with a dummy load and a
brick on a straight key to discovered that the RigRunner part of
the system wasn't able to carry full transmit load. Now there is
a wire directly from the battery junction connector to the K3.
Note that in an automotive installation, you need to fuse both
the positive and negative leads. Fusing the positive lead is
enough to cover most of the obvious failures -- radio develops
dead short, a bare wire touches chassis etc. If the lead between
the negative side of the battery and the chassis of the car (or
a bolt on the engine) becomes loose, then when cranking the
starter, the current from the starter may find a route through
your antenna connection, radio and back to the battery. You want
a fuse that will blow if this rare situation occurs.
73 Bill AE6JV
On 3/16/15 at 1:12 PM, kk4...@gmail.com (John, 9H5G) wrote:
My K3 is powered from a car battery as I am always /P. I have
installed fast-blow fuses rated at 25 A in each of the supply lines.
Operating at 80W RTTY this afternoon, I noted that I was
getting a low voltage warning before I would have expected it.
On examining the power cable, I found the fuse holders to be
warm to the touch. I expect that is what was causing the
voltage drop.
-----------------------------------------------------------------------
Bill Frantz | Truth and love must prevail | Periwinkle
(408)356-8506 | over lies and hate. | 16345
Englewood Ave
www.pwpconsult.com | - Vaclav Havel | Los Gatos,
CA 95032
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net
This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com
