diff --git a/script/jitter_scan.py b/script/jitter_scan.py
index 6f25eed..f2a907c 100644
--- a/script/jitter_scan.py
+++ b/script/jitter_scan.py
@@ -1,14 +1,25 @@
+"""
+File:            jitter_scan.py
+Author:          KR84
+Copyright        PSI LLRF, 2016
 
+Purpose          Record RF system jitters and store / archive data
+Preconditions    RF station is running
 
+"""
 
-import  ch.psi.pshell.epics.ProcessVariable as PV
-
-
-
-latency = 0.3
-
-
+#################################################################
+# Parameter SECTION, change it to your RF station before run
 SECTION = "SINSB02"
+#################################################################
+
+
+
+
+
+# some other parameters
+# for 100 Hz and P2P-count = 100 this can be 1.1 seconds
+latency = 0.3
 start = -170.0
 stop = 180.0
 step = 10.0
@@ -19,10 +30,12 @@ print "Stop = ", stop
 print "Step = ", step
 
 
+# re-define filename, such that the SECTION is also in the filename
 set_context(path = "{data}/{year}_{month}/{date}/{date}_{time}_"  + str(SECTION) + "_{name}") 
 
 
 # define all PVs
+import  ch.psi.pshell.epics.ProcessVariable as PV
 # controlled variabales
 cv_rf_phase = PV("phase_ref", SECTION + "-RLLE-DSP:PHASE-REFERENCE")
 cv_rf_amplt = PV("amplt_ref", SECTION + "-RLLE-DSP:AMPLT-REFERENCE")
@@ -104,7 +117,7 @@ set_attribute(path, "kly_jit_phase_mean", kly_jit_phase_mean)
 
 # ELOG
 msg = scan_result.print("\t")
-msg = msg + "\nMean:\nREF amplt\t" + str(ref_jit_amplt_mean) + "\nREF phase\t" + str(ref_jit_phase_mean) + "\n\nIQM amplt\t" + str(iqm_jit_amplt_mean) + "\nIQM phase\t" + str(iqm_jit_phase_mean) + "\n\nPRE amplt\t" + str(pre_jit_amplt_mean) + "\npre phase\t" + str(pre_jit_phase_mean) + "\n\nKLY amplt\t" + str(kly_jit_amplt_mean) + "\nkly phase\t" + str(kly_jit_phase_mean)
+msg = msg + "\nMean:\nREF amplt\t" + str(ref_jit_amplt_mean)[:5] + "\nREF phase\t" + str(ref_jit_phase_mean)[:5] + "\n\nIQM amplt\t" + str(iqm_jit_amplt_mean)[:5] + "\nIQM phase\t" + str(iqm_jit_phase_mean)[:5] + "\n\nPRE amplt\t" + str(pre_jit_amplt_mean)[:5] + "\npre phase\t" + str(pre_jit_phase_mean)[:5] + "\n\nKLY amplt\t" + str(kly_jit_amplt_mean)[:5] + "\nkly phase\t" + str(kly_jit_phase_mean)[:5]
 msg = msg + "\n\nFile: " + get_context().path
 
 print msg