[Elecraft] AGC Alignment

[Evert Bakker]

Hi all,

I'm assembling the K2 here (SN 4836) and came to the first 
check/alignment.  No smoke here so far, but when adjusting the setting 
for the AGC as described on page 47 I became suspicious about the 
alignment procedure. Adjust R1 for 3.80 V on the DMM. I turned R1 and 
reached the end and got stuck on 3.78V. The absolute value of 3.78 
doesn't worry me but that I ended up at the limit of the R1. I thought I 
should check all variables like DC voltage which should be 8V (was 7.98V 
so OK). Checked the resistors (mainly RP6 / 5.1K) and, RF gain 
potentiometer 5K and the R1 (50K). All looked fine. So what's wrong?

I started making calculation on the resistor dividing network and came 
to the conclusion that the maximum voltage (theoretically) could be 
close to 3.82V when the RF-gain is fully CW  (0 Ohm) and  the R1 is set 
fully CCW (50K).

I wonder if something is wrong here and if not, why was the alignement 
procerdure setup like this (it could heve been something like: Set 
RF-Gain full CW, R1 full CCW and check the voltage at pin 5 of U2 to be 
close to3.80V)? Or did I miss some errata info?

Please help.

Thanks in advance

Evert, PA2KW