About a month ago I was playing around with the HT jumper on one of my OT2m's 
and inadvertently put it on wrong end of the jumper header.  I had shorted the 
12V pin to the unmarked pin below it and my OT2m went dead.  On tracing the 
circuit the unmarked pin seems to be connected to pin 25 of the MCU 
(PTA5/ADC5), so I must have applied 12V to that port! The main consequence was 
that the MCU started to get hot.

After an e-mail exchange with Scott, I sent the unit to him.  I got it back in 
under 3 weeks (to Canada no less).  Very fast turn around and it works once 
again.  Scott really provided fantastic support. He also changed the EQ 
capacitor C2.

Scott had mentioned that he had pulled that unmarked pin from his units to 
prevent that happening.  I was going to drill out one of the via's, but then 
decided to use small diameter heatshrink tubing over the unmarked pin.  Seems 
to work fine.  

By the way I did the same with the other unmarked pin on the lower right (under 
the one marked G).  Don't know what it does (connected to pin 26?), but why 
tempt fate!

The tubing can be removed if there might be need to access these pins at some 
point.

I did not see anything posted, so thought it was worthwhile mentioning so 
others don't make the same mistake.    

Graham  VE6GW 

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