[Elecraft] K2 Power levels.

Don Wilhelm w3fpr at embarqmail.com
Sat Apr 3 15:04:48 EDT 2010


Pete,

First, make certain the ATU menu in the K2 is set to CALP, then check 
again.  I am guessing that the tuner may have been tuned for a 
particular antenna - and since the K2 remembers the tuner settings per 
band, you may be trying to drive a very bad SWR at the antenna input.  
The CALP and CALS settings bypass the L/C section of the tuner.

If you get the same results, yes, go through the Bandpass Filter 
alignment (if you did not get a manual with that K2, download one from 
the Elecraft website.  You must align the  bands in a particular order, 
so follow the order listed in the manual initially.  One note on the 160 
and 80 meter bandpass filter alignment - peak the two inductors for 80 
meters first, then mke note of the position of the slugs - then peak the 
filter on 160 - the position of the slugs may be different, so set the 
inductor slugs to a point midway between the 160 and the 80 meter peaks.
Also note that the frequency on the band is important in some cases.   I 
use 3750 on 80 and 1850 on 160.  Most other bands should be set at 100 
kHz from the bottom of the band, except for 10 meters I find that using 
28.4 MHz provides the best overall coverage of 10.

If peaking the Bandpass filters does not bring the output up to where it 
should be (12+ watts with a 13.8 volt power source, except for 10 meters 
where 10 watts is more likely).  One other point, set CAL CUR to 3.50 
Amps - I know the manual says 2.50, but many K2s now require a bit more 
current. 

If the bandpass filter alignment does not provide sufficient output, you 
likely have another problem somewhere - let us know and we may be able 
to help.  Should that occur, prepare yourself to do some Signal Tracing, 
so you will need either an osciloscope or an RF Probe.  If you have 
neither, Elecraft does sell an RF probe kit - one is shipped with every 
K2 sold, so if the prior owner gave you everything, it is 'in the box'.  
You may need the internal counter probe too if you did not get one with 
the K2.

One other point - I do not recommend running the K2 at maximum output 
(more from a "clean signal" standpoint), but limit the power setting to 
10 watts.  the extra 2 or 3 watts will not make any difference at the 
receiving end, so do resist that temptation to "squeeze every last drop 
out of it".

73,
Don W3FPR

Pete.Milsom wrote:
> Hi Guys
>                 Have been checking the power output of a K2 that I have acquired and found the following results;
>
> 1.9mhz.............2w.
> 3.6mhz.............20w.
> 7.08mhz...........6w.
> 10.103mhz.......5.5w.
> 14.13mhz.........15w.
> 18.1mhz...........15w.
> 21.04mhz.........14w.
> 24.92mhz.........10w.
> 28.2mhz...........9w.
>
> Its is fitted with the auto atu.
>
> Measured into a 50ohm dummy load and external power meter.
>
> Looking at the figures I would guess that possibly it needs an alignment tweek or two but I may be wrong, so I am really just asking for some body with experience to put me in the right direction.
>
> 73 de Pete.
>   
>


More information about the Elecraft mailing list