[Elecraft] K Line Power Requirements

[Ron D'Eau Claire]

Keep in mind too that, when running the KPA500, the K3 is loafing along at
somewhere below 40% of maximum output, so the demands on your d-c supply are
much lower at 500 watts than at 100 watts. 

The bottom line is that you can run at least two full K-line stations from
your Astron 70 without pushing it at all.

73, 

Ron AC7AC

-----Original Message-----

Jack,

The KPA500 power comes from the AC receptacle, not a 13.8 volt power 
supply, so take 20 amps off that total.  And since you do not transmit 
on both the FT-7800 and the K3 at the same time, you do not have to add 
the 8.5 amps.
As I sum the maximum required currents that will be drawn at any one 
time, 21 amps will suffice.

On 8/5/2011 5:18 PM, Jack Regan wrote:
> The specifications according to the manuals are:
>
> K3                          20.0  A (recommended) 3-4 (typical)
NOTE:
> When barefoot I run 100 Watts for CW, SSB and RTTY
> P3                           00 .5 A
> KPA500                 20.0  A
> FT-7800                00.5 A    RCV
> NOTE: 6M, 2M, 440. Squelched. I sometimes have this on scan when working
HF.
> 08.5 A    XMT                                                       NOTE:
I
> do not think I have ever transmitted on both at the same time.
>
> Do I really need a 49.5 amp continuous output PS?
>
> I have an ASTRON RS-70M that has been running for 10 years with no
problems.
> I was hoping to get a smaller, lighter supply to help simplify my setup.
> This is one of the reasons I am thinking of the KPA500, in spite of its
high
> price.
> One alternative I am considering is the MFJ-4245M.