[Elecraft] Re: K2 Noise Blanker Question

Thu May 22 11:42:00 2003

James,

Your reading on pins 1 and 8 are quite a bit off. Pin 1 should be about 6 volts
(U2 is a 6V regulator). If it's closer to 5V, U2 is either the wrong type of
regulator, is defective, has an excessive load on its output, or is in backward.
More glaring is that pin 8 should be 0 V (this pin is suppose to be grounded).
If you're seeing 2.6 volts on this pin, it must not be connected to ground. Look
for a broken ground trace or an unsoldered pin. 

Pin 7 is also suspect. The gate of Q6 shuld not load this pin at all, so it
should be either 0.00 or nearly equal to the voltage at pin 1.

Chances are all of these anomalous readings are related. Let me know what you find.

Wayne
N6KR

[email protected] wrote:
> 
> Wayne,
>    I made the measurements of U3. Here's what I got..
> Pin 1 4.93 volts
> Pin 2 0.00 volts
> Pin 3 5.55 volts
> Pin 4 5.55 volts
> Pin 5 0.00 volts
> Pin 6 0.00 volts
> Pin 7 0.30 volts
> Pin 8 2.60 volts
> 
> C9 is a "102" .001
> R6 is a 220 ohm (red red brown)
> 
> All leads were trimmed flush of all components..
> 
> 73,
> James
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