Re: No TX, No RX, no LCD #chat


ajparent1/KB1GMX
 

As Fred said some of the ICs use 3.3V, some 5V and a few 12-13V

Likely cause is IC11 voltage regulator in backward or a short from pins 1 to 3.
POOF, happens then.

The parts that do not like more than 5V (give or take 10%):
Microprocessor, (5V max)
SI5351 NPLL (3.3V)
FST3253 (5V)
74ACT00 (5v)

Soldering in the 5351 and FST3253 is SMT tech and if you skills are not up
to it try it, or build another as lack of SMT removal skills will generally
destroy the board..

Allison
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