diff --git a/makefile b/makefile
index d2639f1a..e233e877 100644
--- a/makefile
+++ b/makefile
@@ -1434,20 +1434,6 @@ B5500 = ${B5500D}/b5500_cpu.c ${B5500D}/b5500_io.c ${B5500D}/b5500_sys.c \
 	${B5500D}/b5500_dr.c ${B5500D}/b5500_dtc.c
 B5500_OPT = -I.. -DUSE_INT64 -DB5500 -DUSE_SIM_CARD
 
-###
-### Experimental simulators
-###
-
-CDC1700D = CDC1700
-CDC1700 = ${CDC1700D}/cdc1700_cpu.c ${CDC1700D}/cdc1700_dis.c \
-        ${CDC1700D}/cdc1700_io.c ${CDC1700D}/cdc1700_sys.c \
-        ${CDC1700D}/cdc1700_dev1.c ${CDC1700D}/cdc1700_mt.c \
-        ${CDC1700D}/cdc1700_dc.c ${CDC1700D}/cdc1700_iofw.c \
-        ${CDC1700D}/cdc1700_lp.c ${CDC1700D}/cdc1700_dp.c \
-        ${CDC1700D}/cdc1700_cd.c ${CDC1700D}/cdc1700_sym.c \
-        ${CDC1700D}/cdc1700_rtc.c
-CDC1700_OPT = -I ${CDC1700D}
-
 BESM6D = BESM6
 BESM6 = ${BESM6D}/besm6_cpu.c ${BESM6D}/besm6_sys.c ${BESM6D}/besm6_mmu.c \
         ${BESM6D}/besm6_arith.c ${BESM6D}/besm6_disk.c ${BESM6D}/besm6_drum.c \
@@ -1493,6 +1479,20 @@ ifneq (,$(BESM6_BUILD))
   endif
 endif
 
+###
+### Experimental simulators
+###
+
+CDC1700D = CDC1700
+CDC1700 = ${CDC1700D}/cdc1700_cpu.c ${CDC1700D}/cdc1700_dis.c \
+        ${CDC1700D}/cdc1700_io.c ${CDC1700D}/cdc1700_sys.c \
+        ${CDC1700D}/cdc1700_dev1.c ${CDC1700D}/cdc1700_mt.c \
+        ${CDC1700D}/cdc1700_dc.c ${CDC1700D}/cdc1700_iofw.c \
+        ${CDC1700D}/cdc1700_lp.c ${CDC1700D}/cdc1700_dp.c \
+        ${CDC1700D}/cdc1700_cd.c ${CDC1700D}/cdc1700_sym.c \
+        ${CDC1700D}/cdc1700_rtc.c
+CDC1700_OPT = -I ${CDC1700D}
+
 ###
 ### Unsupported/Incomplete simulators
 ###
@@ -1525,20 +1525,22 @@ PDQ3D = PDQ-3
 PDQ3 = ${PDQ3D}/pdq3_cpu.c ${PDQ3D}/pdq3_sys.c ${PDQ3D}/pdq3_stddev.c \
     ${PDQ3D}/pdq3_mem.c ${PDQ3D}/pdq3_debug.c ${PDQ3D}/pdq3_fdc.c 
 PDQ3_OPT = -I ${PDQ3D} -DUSE_SIM_IMD
-
-
 #
-# Build everything (not the unsupported/incomplete simulators)
+# Build everything (not the unsupported/incomplete or experimental simulators)
 #
 ALL = pdp1 pdp4 pdp7 pdp8 pdp9 pdp15 pdp11 pdp10 \
 	vax microvax3900 microvax1 rtvax1000 microvax2 vax730 vax750 vax780 vax8600 \
 	nova eclipse hp2100 hp3000 i1401 i1620 s3 altair altairz80 gri \
 	i7094 ibm1130 id16 id32 sds lgp h316 cdc1700 \
 	swtp6800mp-a swtp6800mp-a2 tx-0 ssem b5500 isys8010 isys8020 \
-	isys8030 isys8024
+	isys8030 isys8024 imds-225
 
 all : ${ALL}
 
+EXPERIMENTAL = cdc1700 
+
+experimental : $(EXPERIMENTAL)
+
 clean :
 ifeq ($(WIN32),)
 	${RM} -r ${BIN}