[Elecraft] A "My K3's coming question"

[Lyle Johnson]

> Is there a wiring diagram for the "optimum" K3 RS-232 cable anywhere?
> I know people are saying "use a standard serial cable"...

For normal use, you just needs pins 2, 3 and 5, plus the shield to the 
connector shell.

If you want to support DTR or RTS signaling (for PTT and/or KEY from a 
logging program, for example) then you also need pins 4 and 7.  The 
remaining pins (1, 6, 8 and 9) are currently not connected in the K3. 
They will cause no harm if they are present, and you lose no 
functionality if they are not.

> I'd also like to make up audio interface cables.

6.5mm (1/4") stereo for front panel headphones, 3.5mm (1/8") stereo for 
rear panel jacks.  The rear panel mic is mono, using tip and shell, so a 
3.5mm mono plug could be used.  I suggest using a 3.5mm stereo connector 
anyway.

The rear apron connectors are so-called RCA or phono, at least here in 
the USA.

73,

Lyle KK7P