diff --git a/pykat/ifo/aplus/files/design.kat b/pykat/ifo/aplus/files/design.kat
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+%%% FTblock header
+#--------------------------------------------------------------------------
+# An A+ design file originlly made for the BHD workshop in October 2018.
+# This file is based on the full design aLIGO model and then adapted for
+# the new design choices
+#--------------------------------------------------------------------------
+# CHANGES
+#--------------------------------------------------------------------------
+%%% FTend header
+
+
+%%% FTblock laser
+###########################################################################
+# Laser and input optics
+l L0 125 0.0 0.0 ni
+bs jitter 1 0 0 0 ni n0 dump dump
+
+s lmod1 1 n0 n1
+
+# modulators for core interferometer sensing - Advanced LIGO, CQG, 2015 
+# http://iopscience.iop.org/article/10.1088/0264-9381/32/7/074001/meta#cqg507871s4-8
+# 9MHz (CARM, PRC, SRC loops)
+const f1 9099471
+const f2 45497355
+
+mod mod1 $f1 0.18 1 pm n1 n2
+s lmod2 1 n2 n3
+
+# 45MHz (MICH, SRC loops)
+mod mod2 $f2 0.18 1 pm n3 nLaserOut
+###########################################################################
+%%% FTend laser
+
+%%% FTblock IMC
+#####################################################################################
+s sIMCin 0 nLaserOut nMC1in
+
+bs1 MC1 6000u 0 0 44.59 nMC1in nMC1refl nMC1trans nMC1fromMC3
+s sMC1_MC2 16.24057 nMC1trans nMC2in
+
+bs1 MC2 0 0u 0 0.82 nMC2in nMC2refl nMC2trans dump
+s sMC2_MC3 16.24057 nMC2refl nMC3in
+attr MC2 Rc 27.24
+
+bs1 MC3 6000u 0 0 44.59 nMC3in nMC3refl nMC3trans nMCreturn_refl
+s sMC3substrate 0.0845 $nsilica nMC3trans nMC3ARin
+bs2 MC3AR 0 0 0 28.9661 nMC3ARin dump nIMCout dump
+
+s sMC3_MC1 0.465 nMC3refl nMC1fromMC3
+#####################################################################################
+%%% FTend IMC
+
+%%% FTblock HAM2
+#####################################################################################
+s sHAM2in 0.4282 nIMCout nIM11
+
+# IM1 a.k.a. SM1
+bs1 IM1 0 0 0 53 nIM11 nIM12 dump dump
+
+s sIM1_IM2 1.2938 nIM12 nIM21
+
+# IM2 a.k.a. PMMT1
+bs1 IM2 0 0 0 7 nIM21 nIM22 dump dump
+attr IM2 Rc 12.8
+
+s sIM2_FI 0.260 nIM22 nFI1
+
+# Input faraday isolator
+dbs FI nFI1 nFI2 nFI3 nREFL
+
+s sFI_IM3 0.910 nFI3 nIM31
+
+# IM3 a.k.a PMMT2
+bs1 IM3 0 0 0 7.1 nIM31 nIM32 dump dump
+attr IM3 Rc -6.24
+
+s sIM3_IM4 1.210 nIM32 nIM41
+
+# a.k.a SM2
+bs1 IM4 0 0 0 45 nIM41 nHAM2out dump dump
+#####################################################################################
+%%% FTend HAM2
+
+%%% FTblock PRC
+###########################################################################
+s sPRCin 0.4135 nHAM2out nPRM1
+
+# PRM
+# AR surface
+m2 PRMAR 0 40u 0 nPRM1 nPRMs1
+# Substrate
+s sPRMsub1 0.0737 $nsilica nPRMs1 nPRMs2
+# HR surface
+m1 PRM 0.03 8.5u $phi_PRM nPRMs2 nPRM2
+attr PRM Rc 11.009
+# Distance between PRM and PR2
+s lp1 16.6107 nPRM2 nPR2a
+# PR2
+bs1 PR2 250u $Mloss 0 -0.79 nPR2a nPR2b nPOP nAPOP
+attr PR2 Rc -4.545 
+# Distance from PR2 to PR3
+s lp2 16.1647 nPR2b nPR3a
+# PR3
+bs1 PR3 0 $Mloss 0 0.615 nPR3a nPR3b dump dump
+attr PR3 Rc 36.027
+# Distance from PR3
+s lp3 19.5381 nPR3b nPRBS
+
+###########################################################################
+%%% FTend PRC
+
+%%% FTblock BS
+###########################################################################
+# BS beamsplitter
+##------------------------------------------------------------ 
+## BS 
+##                             ^ 
+##                  to IMY     |      
+##                             |      ,'-.
+##                             |     +    `. 
+##                        nYBS |   ,'       :'
+##      nPR3b                  |  +i1      +
+##         ---------------->    ,:._  i2 ,'
+##    from the PRC       nPRBS + \  `-. + nXBS
+##                           ,' i3\   ,' --------------->
+##                          +      \ +     to IMX
+##                        ,'     i4.'
+##                       `._      ..
+##                          `._ ,' |nSRBS
+##                             -   |
+##                                 |to the SRC
+##                                 |
+##                                 v
+##------------------------------------------------------------
+bs1 BS 0.5 $Mloss $phi_BS 45 nPRBS nYBS nBSi1 nBSi3
+s BSsub1 0.0687 $nsilica nBSi1 nBSi2
+s BSsub2 0.0687 $nsilica nBSi3 nBSi4
+bs2 BSAR1 50u 0 0 -29.195 nBSi2 dump14 nXBS nPOX
+bs2 BSAR2 50u 0 0 29.195 nBSi4 dump15 nSRBS dump16
+
+###########################################################################
+%%% FTend BS
+
+%%% FTblock Yarm
+###########################################################################
+# Distance from beam splitter to Y arm input mirror
+s ly1 5.0126 nYBS nITMY1a
+
+lens ITMY_lens $SLY_f nITMY1a nITMY1b
+s sITMY_th2 0 nITMY1b nITMY1
+
+# Y arm input mirror
+m2 ITMYAR 0 20u 0 nITMY1 nITMYs1
+s ITMYsub 0.2 $nsilica nITMYs1 nITMYs2
+m1 ITMY 0.014 $Mloss $phi_ITMY nITMYs2 nITMY2
+attr ITMY Rc -1934
+
+# Y arm length
+s LY $Larm nITMY2 nETMY1
+
+# Y arm end mirror
+m1 ETMY 5u $Mloss $phi_ETMY nETMY1 nETMYs1
+s ETMYsub 0.2 $nsilica nETMYs1 nETMYs2
+m2 ETMYAR 0 500u 0 nETMYs2 nPTY
+attr ETMY Rc 2245
+attr ETMY mass 40
+attr ITMY mass 40
+
+###########################################################################
+%%% FTend Yarm
+
+%%% FTblock Xarm
+###########################################################################
+
+# Distance from beam splitter to X arm input mirror 
+s lx1 4.993 nXBS nITMX1a
+
+lens ITMX_lens $SLX_f nITMX1a nITMX1b
+s sITMX_th2 0 nITMX1b nITMX1
+
+# X arm input mirror
+m2 ITMXAR 0 20u 0 nITMX1 nITMXs1 
+s ITMXsub 0.2 $nsilica nITMXs1 nITMXs2
+m1 ITMX 0.014 $Mloss $phi_ITMX nITMXs2 nITMX2
+attr ITMX Rc -1934
+
+# X arm length
+s LX $Larm nITMX2 nETMX1
+
+# X arm end mirror
+m1 ETMX 5u $Mloss $phi_ETMX nETMX1 nETMXs1
+s ETMXsub 0.2 $nsilica nETMXs1 nETMXs2
+m2 ETMXAR 0 500u 0 nETMXs2 nPTX 
+attr ETMX Rc 2245
+attr ETMX mass 40
+attr ITMX mass 40
+
+###########################################################################
+%%% FTend Xarm
+
+%%% FTblock SRC
+###########################################################################
+# Distance to SR3
+s ls3 19.3661 nSRBS nSR3b
+# SR3
+bs1 SR3 0 $Mloss 0 0.785 nSR3b nSR3a dump dump
+attr SR3 Rc 35.972841
+# Distance from SR3 to SR2
+s ls2 15.4435 nSR3a nSR2b
+# SR2
+bs1 SR2 0 $Mloss 0 -0.87 nSR2b nSR2a dump dump
+attr SR2 Rc -6.406
+# Distance from SR2 to SRM
+s ls1 15.7586 nSR2a nSRM1
+# Signal recycling mirror SRM-08
+m1 SRM 0.32 8.7u $phi_SRM nSRM1 nSRMs1
+s SRMsub 0.0749 $nsilica nSRMs1 nSRMs2
+m2 SRMAR 0 50n 0 nSRMs2 nSRM2
+attr SRM Rc -5.6938
+
+s sSRM_FI 0.7278 nSRM2 nFI2a
+
+###########################################################################
+%%% FTend SRC
+
+%%% FTblock OUTPATH
+###########################################################################
+# Directional beam splitter (ideal Faraday Isolator with 4 ports)
+# ----------------------------------------------------------------
+# Description of node connections, inputNode --> outputNode
+# --
+# nFI2a (SRM)    --> nFI2c (OMC)
+# nFI2b (SQZ)    --> nFI2a (SRM)
+# nFI2c (OMC)    --> nFI2d (Unused)
+# nFI2d (Unused) --> nFI2b (SQZ)
+
+dbs FI2 nFI2a nFI2b nFI2c nFI2d
+
+# Distance FI2 --> OM0, length guess
+s sFI_OMo 2 nFI2c nOM0a
+
+# Initial steering mirror on HAM6 for AS
+bs1 OM0 0.008 0 0 45 nOM0a nOM0b nAS nOM0d
+
+s sOM0_BHDBS 1 nOM0b nBHDBSc # OM0 to BHD BS, length guess
+
+# BHD BS
+bs1 BHDBS 0.5 0 0 45 nBHDBSa nBHDBSb nBHDBSc nBHDBSd
+
+# Path from BHD BS to OMCA
+s sBSHD_OMA1 1 nBHDBSa nOMA1a 
+bs1 OMA1 0 0 0 0 nOMA1a nOMA1b dump dump
+s sOMA1_OMA2 1.5 nOMA1b nOMA2a 
+bs1 OMA2 0 0 0 0 nOMA2a nOMA2b dump dump
+s sOMA2_OMA3 1 nOMA2b nOMA3a
+bs1 OMA3 0 0 0 45 nOMA3a nOMA3b dump dump
+s sOMA3_OMC 0.5 nOMA3b nOMCA_ICa 
+
+attr OMA1 Rc 1.037
+attr OMA2 Rc 1.239
+
+# Path from BHD BS to OMCB
+s sBSHD_OMB1 1 nBHDBSd nOMB1a 
+bs1 OMB1 0 0 0 0 nOMB1a nOMB1b dump dump
+s sOMB1_OMB2 1.5 nOMB1b nOMB2a 
+bs1 OMB2 0 0 0 0 nOMB2a nOMB2b dump dump
+s sOMB2_OMB3 1 nOMB2b nOMB3a
+bs1 OMB3 0 0 0 45 nOMB3a nOMB3b dump dump
+s sOMB3_OMC 0.5 nOMB3b nOMCB_ICa 
+
+attr OMB1 Rc 1.037
+attr OMB2 Rc 1.239
+###########################################################################
+%%% FTend OUTPATH
+
+
+%%% FTblock LO
+###########################################################################
+# ref G1800283
+s sPR2_LOM 5 nPOP nLOMa
+bs LOM 1 0 0 45 nLOMa nLOMb dump dump
+s LOM_LOLens 5 nLOMb nLOLensa
+lens LOLens -12.8 nLOLensa nLOLensb
+s sLOLens_BHDBS 1 nLOLensb nBHDBSb
+###########################################################################
+%%% FTend LO
+
+
+%%% FTblock OMCA
+###########################################################################
+# OMCA (as built parameters original OMC: D1300507-v1)
+bs1 OMCA_IC 0.0076 10u 0 2.7609 nOMCA_ICa nOMCA_ICb nOMCA_ICc nOMCA_ICd  # Input Coupler IC (flat mirror)
+s sICA_OCA 0.2815 1 nOMCA_ICc nOMCA_OCa                                    # Distance from IC to OC  
+bs1 OMCA_OC 0.0075 10u 0 4.004 nOMCA_OCa nOMCA_OCb nBHD1 nOMCA_OCd       # Output Coupler OC (flat mirror)
+s sOCA_CMA1 0.2842 1 nOMCA_OCb nOMCA_CM1a                                  # Output Coupler OC (flat mirror)
+bs1 OMCA_CM1 36u 10u 0 4.004 nOMCA_CM1a nOMCA_CM1b nOMCA_CM1c nOMCA_CM1d # Curved Mirror CM1
+attr OMCA_CM1 Rc 2.57321
+s sCMA1_CMA2 0.2815 1 nOMCA_CM1b nOMCA_CM2a                                # Curved Mirror CM1
+bs1 OMCA_CM2 35.9u 10u 0 4.004 nOMCA_CM2a nOMCA_CM2b nOMCA_CM2c nOMCA_CM2d # Curved Mirror CM2
+attr OMCA_CM2 Rc 2.57369
+s sCMA1_ICA 0.2842 1 nOMCA_CM2b nOMCA_ICd                                  # Distance from CM2 to IC
+###########################################################################
+%%% FTend OMCA
+
+
+%%% FTblock OMCB
+###########################################################################
+# OMCB (as built parameters original OMC: D1300507-v1)
+bs1 OMCB_IC 0.0076 10u 0 2.7609 nOMCB_ICa nOMCB_ICb nOMCB_ICc nOMCB_ICd  # Input Coupler IC (flat mirror)
+s sICB_OCB 0.2815 1 nOMCB_ICc nOMCB_OCa                                    # Distance from IC to OC  
+bs1 OMCB_OC 0.0075 10u 0 4.004 nOMCB_OCa nOMCB_OCb nBHD2 nOMCB_OCd       # Output Coupler OC (flat mirror)
+s sOCB_CMB1 0.2842 1 nOMCB_OCb nOMCB_CM1a                                  # Output Coupler OC (flat mirror)
+bs1 OMCB_CM1 36u 10u 0 4.004 nOMCB_CM1a nOMCB_CM1b nOMCB_CM1c nOMCB_CM1d # Curved Mirror CM1
+attr OMCB_CM1 Rc 2.57321
+s sCMB1_CMB2 0.2815 1 nOMCB_CM1b nOMCB_CM2a                                # Curved Mirror CM1
+bs1 OMCB_CM2 35.9u 10u 0 4.004 nOMCB_CM2a nOMCB_CM2b nOMCB_CM2c nOMCB_CM2d # Curved Mirror CM2
+attr OMCB_CM2 Rc 2.57369
+s sCMB1_ICB 0.2842 1 nOMCB_CM2b nOMCB_ICd                                  # Distance from CM2 to IC
+###########################################################################
+%%% FTend OMCB
+
+%%% FTblock cavities
+###########################################################################
+cav cavIMC MC2 nMC2in MC2 nMC2refl 
+cav cavXARM ITMX nITMX2 ETMX nETMX1
+cav cavYARM ITMY nITMY2 ETMY nETMY1
+cav cavSRX SRM nSRM1 ITMX nITMXs2
+cav cavSRY SRM nSRM1 ITMY nITMYs2
+cav cavPRX PRM nPRM2 ITMX nITMXs2
+cav cavPRY PRM nPRM2 ITMY nITMYs2
+cav cavOMCA OMCA_IC nOMCA_ICc OMCA_IC nOMCA_ICd
+cav cavOMCB OMCB_IC nOMCB_ICc OMCB_IC nOMCB_ICd
+
+###########################################################################
+%%% FTend cavities
+
+%%% FTblock constants
+###########################################################################
+const nsilica 1.44963098985906
+const nTGG 1.954
+const nCalcite 1.65846
+const Mloss 37.5u
+const Larm 3994.4692
+const fM 36.397884M
+const fP 54.596826M
+const TLY_f 34.5k         # Thermal lens ITMY
+const TLX_f 34.5k         # Thermal lens ITMX
+const SLY_f inf           # Substrate lens ITMY
+const SLX_f inf           # Substrate lens ITMX
+const th_f 34.5k
+###########################################################################
+%%% FTend constants
+
+%%% FTblock tunings
+###########################################################################
+const phi_SRM 90.0
+const phi_PRM 0.0
+const phi_ITMX 0.0
+const phi_ITMY 0.0
+const phi_ETMX 0.0
+const phi_ETMY 0.0
+const phi_BS 0
+###########################################################################
+%%% FTend tunings
\ No newline at end of file