Neil,
Yes you apparently have something wrong.
The voltage measurement comes from a purely resistive network fed by 8
volts, and there is not much to troubleshooting it - that is if you can
manage to probe the pins of R-Pak RP6.
With the RF gain in the full clockwise setting, you should read close to 0
volts on pin 6 of RP6 - and you should find 8 volts from the power source on
pin 3 (of RP6). The voltage at pins 4 and 5 should be at the same voltage
as pin 5 of U6, and the voltage should be adjustable by changing R1. The
voltage on pin 7 of RP1 will depend on the setting of R1. Check out the
schematic of the Control Board - look in the AGC section in the lower left
corner to see how these resistors are connected.
If you find a voltage that is unusual, first check the soldering, and next
be certain RP6 is the 5.1k package (the numbers 512 should appear in the
labeling).
If the voltage on pin 3 of RP6 is much lower than 8 volts, the 8 volt
regulator (U4) may be the problem. However, the last person I helped who
had a reading similar to yours did not have the probe on pin 5 of U6. Pin 5
is the topmost pin and toward the side panel.
73,
Don W3FPR
----- Original Message ----- >
> I am just at the first alignment and test stage of my K2. Everything
> checked out just fine except the step where I am to adjust R1 on the
> control board for 3.80 v on pin 5 of U2. The highest I can get the voltage
> to go is 3.38v. Is this something to worry about? If so, any clues?
>
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