The problem you are suffering from is that fact that the backticks are an interpolative context. Which means that the $1 you have is interpolated before the call to awk is made. And you have the same for the $0. Putting backslashes before the dollar signs will solve this problem.

However, it doesn't make sense to use backticks here. Backticks run the command, and return the output of the command - however, since your command redirects all output, there's nothing to collect. The following system command you make doesn't make sense - it executes nothing. You'd be better off to use system here, instead of the backticks - and then you can q and avoid $1 and $0 to be interpolated:

system q {awk '$1 ~ /^F/ {print $0 }' /tmp/frhtest/ADDC.bak > /tmp/frh
+test/ADDC.}.$date;
die "Command failed" if $?;
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