[Elecraft] [OT} Running a KX3 station from a holiday trailer

[Jim Brown]

On Fri,7/31/2015 9:35 AM, Al Sather wrote:
> Greetings
>
> I know this is a bit of topic but I this this list has the expertise 
> to give me good answers.
>
> My station is a KX3-KXPA100 with a PX3. I have a quiet, to me, 30 amp 
> switching power and a 2000 watt Honda generator that generates some, 
> but not objectionable noise. 

Great generator, lots of them in our club. There's a fix for the noise.

http://nccc.cc/pdf/CQP-RFI2013-2.pdf  addresses this and a lot of other 
noise sources.


> The NB on the KX3 clears that up totally. I also have a 20 amp liner 
> Astron power supply but it is heavy, bulky for use in a small trailer. 
> And, it may be light for running an amp.
> I course I do not need to run it at 100 watts, either.
>
> I am trying to decide if it best to operate from the trailer's AC or 
> directly from the batteries.
> And, if I use the batteries alone are there precautions I need to take.
> Of course, if available I would use "shore power". The AC from the 
> trailer seems to be adequate when running with or without "shore 
> power" or with my generator.
>
> I guess my real concern is the issue of using DC directly, and what 
> should happen for protecton between my batteries and station.

Since 2004, I've been running all my gear on big 12V deep discharge 
batteries that I "float charge" with a regulated supply set for about 14 
VDC.

  I've never found the need for any protection in line with the gear. We 
do the same on FD, except that we use solar panels to charge the battery.

One thing I have run into with a K3 running from the 12V system in my 
2006 Toyota Sequoia (big SUV). I was operating 6M with the motor off, 
and decided to start it. That somehow interrupted power to the K3 for a 
few seconds, which caused a microprocessor to lose its place. To get it 
going, I had to remove it from the 12V line and let it sit for a while 
(10-15 minutes).

The K3 doesn't like its power to be interrupted. The root cause of the 
problem is that when you turn a K3 off using the front panel, it writes 
its current operating conditions to RAM. When you interrupt power with 
the K3 running, it can't do that.

I don't know how this might relate to the KX3.

73, Jim K9YC