[Elecraft] K2 Ser. No. 784 no audible CW tone when sending

[W3FPR]

Terry,

What is the MCU firmware level?  You can check that by holding any 
button while powering the K2.
If the level is not 2.04R, then the sidetone source is select-able in 
the menu.
I suggest you turn the STL level down to about 30 or so to protect your 
ears.  Then when in the sidetone menu, tap the DISPLAY button to change 
between U6-25 and U8-4.  Exit the menu when you hear sidetone.
Your sidetone source must be U8-4 since the KPA100 is installed.

Upgrading the 2.04R firmware will cure it for all time.

73,
Don W3FPR

On 6/29/2025 5:05 PM, Terry via Elecraft wrote:
> Hello All,
>
>   
>
> Our Ham Club had a K2-100 donated to the club.  At field day, I was going to
> use it to make some CW contacts.  When I keydown the Key, CW is being sent,
> but the speaker goes silent and no audible CW tones are being transmitted.
> I have the St L cranked up to 165.  Regardless of the ST L setting, there is
> no audible CW being heard.  It is sending at power.  Everything seems to
> work except that.
>
>   
>
> I would appreciate anyone giving me advice on what might be wrong.
>
>   
>
>