[Elecraft] Problem with Current Meter

[Don Wilhelm]

Eduardo,

Do you have any voltage at the emitter of Q11?  Is that voltage getting 
to U6 pin 5 (measure on the leg of U6 instead of at the socket).

Check U6 pin 5 - it could be bent under the chip or on the outside of 
the socket.

If the voltage at Q11 emitter is zero, then check the differential 
voltage between pins 2 and 3 of U3.  That differential voltage should 
result in a small voltage at U3 pin 1.

Check R7 and R8 for good soldering.


73,
Don W3FPR

Eduardo Jacob wrote:
> Hi
> 
> A friend of mine is having problems with the current detector. When he
> presses the display button the voltage is displayed but the current 
> shows 0.
> We have been tracing the circuit which is fairly straight and we are not
> able to get the solution. We have changed the LM833 and the PN2222A
> transistor. We have checked the current sense resistor and it seems it's
> working. Does any body found before this problem?
> 
> Regards
> 
> Eduardo/EA2BAJ
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