[Elecraft] RS232/ U1/ failure

[Keith Trinity WE6R]

Sorry guys, I made an error (brain is full).
The fix for cold RS232 comms on OLD KIO3 main board is replace Q1.
We changed this part along the way somewhere.
New part is;
MMBT5088,NPN,SOT23,SMD      ON Semiconductor MMBT5088LT1G     Mouser 
863-MMBT5088LT1G
Elecraft # E580048
(BTW, old part was; Elecraft # E580025, MMBT3904T,NPN,SOT23,SMD       
Digikey    497-2478-2-ND 497-2478-1-ND)
Keith WE6R K3/K4 Tech

_From my own knowledge-base document (had I just looked, hi hi)._
No comms communications RS232 when cold frozen or very low temperatures.
(This is only for older K3’s with the old KIO3 Main board).
Fix: Change Q1 E580048 on KIO3 Main board or sell them the KIO3BUPKT.
The new part we use works OK when very cold.