[Elecraft] K2 - KIO2 connected under power - now it is dead

Dale Boresz [email protected]
Tue Jun 17 06:14:00 2003


Andreas KU7T wrote:

> Hi,
>
> I built the KIO2 and it worked rigth from the beginning, as in good 
> Elecraft tradition. 
> Then, I tried to remote the KPA100/KAT100 and as soon as I plugged the 
> cable in there was a strange smell and nothing worked anymore. I am 
> running on battery, so I think I plugged in under power.  Well, 
> probably not a good thing but I did it. 
>  
>
Andreas,

Check choke L1 (on the AUX Board  - the little board which plugs into 
the 10-pin control board connector) for continuity. Don't get this 
confused with choke L1 on the main KIO2 I/O board which is also 15uH. 
I'll bet that 'strange smell' was L1 burning out, and it is probably now 
'open' conductivity-wise.

L1 passes 12 volts, through via pin 8 of the rear-panel 9-pin "D-Shell" 
connector, and if it is not present, you'll find that FET Q2 on your 
KAT100 will not turn on, which in turn will not allow Q1 to conduct, 
which means that you won't have any power to your KPA100 - despite the 
fact that you still have your external 12 volts connected.

-Dale / WA8SRA