diff --git a/script/jitter_scan.py b/script/jitter_scan.py
index ef4d82a..aec4b6a 100644
--- a/script/jitter_scan.py
+++ b/script/jitter_scan.py
@@ -56,6 +56,9 @@ mv_pre_jit_phase = PV("PRE_phase_jit" ,SECTION + "-RPRE-DCP10:FOR-PHASE-JIT-P2P"
 mv_kly_jit_amplt = PV("KLY_amplt_jit" ,SECTION + "-RKLY-DCP10:FOR-AMPLT-JIT-P2P-REL")
 mv_kly_jit_phase = PV("KLY_phase_jit" ,SECTION + "-RKLY-DCP10:FOR-PHASE-JIT-P2P")
 
+mv_vsum_jit_amplt = PV("VSUM_amplt_jit" ,SECTION + "-RLLE-DSP:VSUM-AMPLT-JIT-P2P")
+mv_vsum_jit_phase = PV("VSUM_phase_jit" ,SECTION + "-RLLE-DSP:VSUM-PHASE-JIT-P2P")
+
 # auxiliary measured variables, but not scanned
 #mva_hvps = PV("HVPS" ,SECTION + "-RMOD:V-SET")
 mva_hvps = PV("HVPS" ,"SINEG01-RMOD:V-SET")
@@ -71,6 +74,8 @@ mv_pre_jit_amplt.initialize()
 mv_pre_jit_phase.initialize()
 mv_kly_jit_amplt.initialize()
 mv_kly_jit_phase.initialize()
+mv_vsum_jit_amplt.initialize()
+mv_vsum_jit_phase.initialize()
 
 mva_hvps.initialize()
 
@@ -98,7 +103,7 @@ amplt_m10 = 0.9  * amplt_stop
 
 
 #scan_result = ascan((cv_rf_phase, cv_rf_amplt), (mv_ref_jit_amplt,mv_ref_jit_phase,mv_iqm_jit_amplt,mv_iqm_jit_phase,mv_pre_jit_amplt,mv_pre_jit_phase,mv_kly_jit_amplt,mv_kly_jit_phase), (-170.0, 0.2), (180.0, 0.3), (10.0, 0.05) , latency=latency, title="Jitter Scan", zigzag=True)
-scan_result = ascan((cv_rf_amplt, cv_rf_phase), (mv_ref_jit_amplt,mv_ref_jit_phase,mv_iqm_jit_amplt,mv_iqm_jit_phase,mv_pre_jit_amplt,mv_pre_jit_phase,mv_kly_jit_amplt,mv_kly_jit_phase), ( 0.2, -170.0), (0.3, 180.0), (0.05, 10.0) , latency=latency, title="Jitter Scan", zigzag=False)
+scan_result = ascan((cv_rf_amplt, cv_rf_phase), (mv_ref_jit_amplt,mv_ref_jit_phase,mv_iqm_jit_amplt,mv_iqm_jit_phase,mv_pre_jit_amplt,mv_pre_jit_phase,mv_kly_jit_amplt,mv_kly_jit_phase,mv_vsum_jit_amplt,mv_vsum_jit_phase), ( 0.2, -170.0), (0.3, 180.0), (0.05, 10.0) , latency=latency, title="Jitter Scan", zigzag=False)
 
 
 
@@ -114,6 +119,8 @@ mv_pre_jit_amplt.close()
 mv_pre_jit_phase.close()
 mv_kly_jit_amplt.close()
 mv_kly_jit_phase.close()
+mv_vsum_jit_amplt.close()
+mv_vsum_jit_phase.close()
 
 mva_hvps.close()
 
@@ -177,6 +184,8 @@ pre_jit_phase = all_statistics_data()
 kly_jit_amplt = all_statistics_data()
 kly_jit_phase = all_statistics_data()
 
+vsum_jit_amplt = all_statistics_data()
+vsum_jit_phase = all_statistics_data()
 
 # calculate statistics
 ref_jit_amplt = all_statistics_calc(scan_result.getReadable(0))
@@ -191,6 +200,9 @@ pre_jit_phase = all_statistics_calc(scan_result.getReadable(5))
 kly_jit_amplt = all_statistics_calc(scan_result.getReadable(6))
 kly_jit_phase = all_statistics_calc(scan_result.getReadable(7))
 
+vsum_jit_amplt = all_statistics_calc(scan_result.getReadable(8))
+vsum_jit_phase = all_statistics_calc(scan_result.getReadable(9))
+
 
 
 
@@ -233,6 +245,9 @@ msg = msg + "\n---------------------------------------------------------"
 msg = msg + "\nKLY amplt\n" + kly_jit_amplt.return_string()
 msg = msg + "\n\nKLY phase\n" + kly_jit_phase.return_string()
 msg = msg + "\n---------------------------------------------------------"
+msg = msg + "\nVSUM amplt\n" + vsum_jit_amplt.return_string()
+msg = msg + "\n\nVSUM phase\n" + vsum_jit_phase.return_string()
+msg = msg + "\n---------------------------------------------------------"
 msg = msg + "\n\nPlots axis: X-axis = Three amplitude setpoints from left to right: 10% below sat / 5% below sat / sat"
 msg = msg + "\n\nData file: " + get_context().path