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Service manual for President grant 409 board

Harley3315

Well-Known Member
Oct 22, 2015
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Need to try to do an alignment to get radio recenter from crappy clarifier mod
found some info but not where test point locations are any help would be awesome.
 

Not sure where I came across this. It is marked "PC409" but check it out before the "tweaking" begins.

73
David
 

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  • GrantPC409alignment.doc
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Not sure where I came across this. It is marked "PC409" but check it out before the "tweaking" begins.

73
David
Yeah not sure what I'm doing wrong I connect the probe to any pin on L21 the counter just rolls around 59hmz or so can't get solid reading in any mode moved past that tried to get reading off of test point 3 also wont read anything in any mode keyd or unkeyed
 
Yeah not sure what I'm doing wrong I connect the probe to any pin on L21 the counter just rolls around 59hmz or so can't get solid reading in any mode moved past that tried to get reading off of test point 3 also wont read anything in any mode keyd or unkeyed
The counter wont lock due to VERY low signal levels usualy associated with ic chips. Also circuit loading may be an issue from your probes. You are gonna need a signal amplifier inline to boost that signal so the counter will lock. Also possibly a cap inline with the probes to prevent any circuit loading effects.
 
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