TM 5-6635-386-12&P
It is most desirable that the operator maintain a standard
count diary with his raw data and his computations
written down. This is most helpful to the repair shop
should the tester require repair for some complaint of
"drift" or "erratic" counts. Use DA Form 5449-R
(Moisture
and
Density
Tester
(Nuclear
Method)
Utilization Log) to record standard counts. DA Form
5449-R is located at the back of this TM for local
reproduction authority.
Figure 1-3. Field Data Worksheet
Note that both standard count series produced a normal split of 3 out of 7 inside the limits of + square root of the average.
A split of 2 out/8 in or 4 out/6 in is normal occasionally, provided the usual split is a 3/7 and provided the average standard
count remains within approximately 1/3 square root of the prior series’ average.
It is perfectly proper to use the Automatic Standard count
for daily routine, but it is very desirable that the full
evaluation be run periodically to ascertain that your tester
is running properly, regardless of make or model.
1-12. WHAT DO POOR RESULTS MEAN?
If the tester consistently exhibits a tendency towards a
high deviation, that is, the calculator method trends more
towards the 1.25 end of the spread than the 0.75 end,
and the manual method trends more towards 4 and 5 out
instead of 2 out, the tester is indicating a tendency
towards erratic counts beyond the normal projected
deviation to be expected.
This erratic tendency is likely to come from a dirty high
voltage supply, dirty detector connectors, or a failing
component in the high voltage supply. Simply dusting off
the supply may eliminate the problems. If this does not
work the tester may require repair.
1-11
