[Elecraft] Line Audio Output Mod

[Joe Planisky]

Sounds like either that mod has already been done or your KIO3 board is newer than you think.  IIRC the original value of R19 and R20 was 600 ohms.  Adding a 51 ohm resistor in parallel gives 47 ohms.  The newer boards have 51 ohm resistors in place of the 600 ohm units. 

Perhaps Elecraft should add a "Does My K3 Have This Modification" section to their older mod instructions. Most of the newer mod instructions have such a section that explains how to tell if the mod has already been done. 

73
--
Joe KB8AP

On Jan 19, 2011, at 3:24 PM, DBellW6AQ at aol.com wrote:

> I'm really confused.  I have a KIO3A, Rev A, C 2007.  According  to the Mod 
> instructions this board should need the resistance  modification.  BEFORE I 
> began the mod, the resistance across R19 and R20  was about 51 ohms each.  
> So how can I put a 51 ohm resistor in parallel  with R19 and 20 and end up 
> with a new resistance of between 45 and 49  ohms?  Thinking there might be a 
> flaw in my thinking somewhere, I added a  leaded resistor across R20 and 
> sure enough, the resistance was now about 26  ohms, so I took it out.
> 
> What gives?  Instructions wrong?  Am I missing something?   Thanks in 
> advance.
> 
> 73, Dave