[Elecraft] K2 keying and voltage display???

[Tom Hammond NØSS]

David:

>I noticed tonight that my K2's keying is very harsh sounding that is on 
>40M, while listening in another rxer. Is there any concern I should have 
>other than my personal taste for nice sine wave keying, Hi Hi. I can live 
>with a harsh sidetone but I would like the transmitted signal to sound a 
>lot better.

Without question, the K2 should have a PERFECT CW note!!! If you don't have 
it, then there IS a problem somewhere.

1) Check your note with the RF GAIN on the external RX turned WAY down. 
Sometimes a 'local' transmitter can overload the front end of an ext. RX 
and cause apparent problems where none exist.

2) Regarding the transmitted signal you DO hear... does it sound like it 
has AC ripple on it? If so, you may have some induces AC ripple from a 
nearby power transformer. Several users have found that their power 
supplies (or those of other nearby devices) had enough electromagnetic 
radiation from the transformer as to 'modulate' something in the K2 (I'm 
guessing the PLL, but not certain). Try moving the K2 (or nearby devices) 
further apart to see if the problem goes away. Does the problem exist when 
using the internal battery?
ANd... on what frequency did you notice this problem? All over the band, or 
possibly just near to 7.185MHz?

Any further 'descriptive' info regarding the 'character' of your CW not 
might be helpful.

>Also, I noticed that the voltage that comes up by pushing the DISPLAY 
>button is off from the input in the back of the rig. My PS is ~13.8VDC, 
>+/- 0.1VDC. The displayed voltage is 13.3VDC with the C at .18, set for 
>maximum mileage out of my batteries, when I run it off batteries. What 
>could be the problem if any here?

Probably NOT a problem!

There are two solid state devices (pritective diode and a solid state fuse) 
in-line with the supply voltage, both located INSIDE the K2. These two 
devices will drop a small amount of voltage across each of their 
junctions... generally 0.6VDC total. So your voltage display SHOULD 
indicate 0.5-0.6VDC LESS than that seem at the DC input port to the rig.

You might want to bump up your supply voltage a bit, too. Wayne recommends 
a 14.1-14.3VDC supply voltage, to ensure that the internal battery is fully 
charged.

73,

Tom Hammond   N0SS