Control board voltages

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Control board voltages

Earl Ritchie-2
I have made up the control board for my K2 and all looks good.  The resistance checks were all within specs except the U5 OUT to gnd which was about 3600 ohms.  Checking further I find the 8R and 8T voltages seem OK but some 5 volt areas are not.  For instance the 0 volts and 5 volts on U7 pins 5&6 are reversed as well as U6 pins 24&25,  U8 pins 10 & 11.  Someone probably has the answer right at their finger tips but I cant see what the problem is.
Earl, VE3FBK
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Re: Control board voltages

Don Wilhelm-3
Earl,

I just scanned the manual and do not see any voltage checks to be done after
the Control Board is completed.  Assuming you obtained the voltage readings
from the rear of the manual, those only correctly pertain to a fully
assembled K2. Some of the digital levels may be reversed until the other
parts of the K2 are complete.  All the points you mentioned are digital
signals - it is sufficient at your stage in building that they are either
close to 0 volts or close to 5 volts (somewhere in the middle would be an
indicator of a potential problem for these digital signals).

73,
Don W3FPR

----- Original Message -----

I have made up the control board for my K2 and all looks good.  The
resistance checks were all within specs except the U5 OUT to gnd which was
about 3600 ohms.  Checking further I find the 8R and 8T voltages seem OK but
some 5 volt areas are not.  For instance the 0 volts and 5 volts on U7 pins
5&6 are reversed as well as U6 pins 24&25,  U8 pins 10 & 11.  Someone
probably has the answer right at their finger tips but I cant see what the
problem is.


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