diff --git a/src/frontend/inp.c b/src/frontend/inp.c
index 89abf2c42..f689652f3 100644
--- a/src/frontend/inp.c
+++ b/src/frontend/inp.c
@@ -40,6 +40,7 @@ Author: 1985 Wayne A. Christopher
 
 #include "numparam/numpaif.h"
 #include "ngspice/stringskip.h"
+#include "ngspice/randnumb.h"
 
 
 #define line_free(line, flag)                   \
diff --git a/src/frontend/numparam/xpressn.c b/src/frontend/numparam/xpressn.c
index 1ec587c8b..87319115d 100644
--- a/src/frontend/numparam/xpressn.c
+++ b/src/frontend/numparam/xpressn.c
@@ -16,8 +16,7 @@
 
 
 /* random numbers in /maths/misc/randnumb.c */
-extern double gauss0(void);
-extern double drand(void);
+#include "ngspice/randnumb.h"
 
 /************ keywords ************/
 
diff --git a/src/frontend/trannoise/wallace.c b/src/frontend/trannoise/wallace.c
index 863768868..8421b2d19 100644
--- a/src/frontend/trannoise/wallace.c
+++ b/src/frontend/trannoise/wallace.c
@@ -20,6 +20,7 @@
 #include <math.h>
 #include "ngspice/wallace.h"
 #include "ngspice/FastNorm3.h"
+#include "ngspice/randnumb.h"
 
 #define POOLSIZE 4096
 #define LPOOLSIZE 12
@@ -42,11 +43,6 @@ static unsigned n = POOLSIZE;
 static double chi1, chi2; /* chi^2 correction values */
 static unsigned int newpools;
 
-extern double drand(void);
-extern unsigned int CombLCGTausInt(void);
-extern void TausSeed(void);
-extern unsigned int CombLCGTausInt2(void);
-
 
 void
 PolarGauss(double* py1, double* py2)
diff --git a/src/include/ngspice/1-f-code.h b/src/include/ngspice/1-f-code.h
index a4ecfd325..8cfd86237 100644
--- a/src/include/ngspice/1-f-code.h
+++ b/src/include/ngspice/1-f-code.h
@@ -1,8 +1,4 @@
-
-extern double drand(void);
-extern double exprand(double);
-extern int poisson(double);
-extern double gauss0(void);
+#include "ngspice/randnumb.h"
 
 void f_alpha(int n_pts, int n_exp, double X[], double Q_d,
 double alpha);
diff --git a/src/include/ngspice/fteext.h b/src/include/ngspice/fteext.h
index 83f5489d7..b5ec9133d 100644
--- a/src/include/ngspice/fteext.h
+++ b/src/include/ngspice/fteext.h
@@ -277,8 +277,6 @@ extern struct plot *raw_read(char *name);
 extern bool do_measure(char *what, bool chk_only);
 extern bool check_autostop(char *what);
 
-/* randnumb.c */
-extern void TausSeed(void);
 /* resource.c */
 
 extern void ft_ckspace(void);
diff --git a/src/include/ngspice/randnumb.h b/src/include/ngspice/randnumb.h
new file mode 100644
index 000000000..d5c53c5e0
--- /dev/null
+++ b/src/include/ngspice/randnumb.h
@@ -0,0 +1,17 @@
+#ifndef ngspice_RANDNUMB_H
+#define ngspice_RANDNUMB_H
+
+/* initialize random number generators */
+extern void initw(void);
+
+extern void checkseed(void);    /* seed random or set by 'set rndseed=value'*/
+extern double drand(void);
+extern double gauss0(void);
+extern int poisson(double);
+extern double exprand(double);
+
+extern void TausSeed(void);
+extern unsigned int CombLCGTausInt(void);
+extern unsigned int CombLCGTausInt2(void);
+
+#endif
diff --git a/src/include/ngspice/wallace.h b/src/include/ngspice/wallace.h
index 2c81bcfc7..2fd36898d 100644
--- a/src/include/ngspice/wallace.h
+++ b/src/include/ngspice/wallace.h
@@ -17,6 +17,4 @@ double NewWa(void); /* generate new pool, return outgauss[0] */
 
 #define GaussWa ((--variate_used)?(outgauss[variate_used]*ScaleGauss):NewWa())
 
-void initw(void); /* initialization of Wallace generator */
-
 void PolarGauss(double* py1, double* py2);
diff --git a/src/main.c b/src/main.c
index 3d83ed4f1..a4e0b6fbc 100644
--- a/src/main.c
+++ b/src/main.c
@@ -52,6 +52,7 @@ extern int rl_catch_signals;        /* missing from editline/readline.h */
 #include "frontend/signal_handler.h"
 #include "frontend/misccoms.h"
 #include "ngspice/compatmode.h"
+#include "ngspice/randnumb.h"
 
 /* saj xspice headers */
 #ifdef XSPICE
@@ -205,8 +206,6 @@ extern void OUTerrorf(int, const char *fmt, ...);
 
 extern int OUTattributes(runDesc *, IFuid, int, IFvalue *);
 
-extern void initw(void);
-
 IFfrontEnd nutmeginfo = {
     IFnewUid,
     IFdelUid,
diff --git a/src/maths/cmaths/cmath2.c b/src/maths/cmaths/cmath2.c
index 076735a5d..db010700b 100644
--- a/src/maths/cmaths/cmath2.c
+++ b/src/maths/cmaths/cmath2.c
@@ -18,18 +18,12 @@ Author: 1985 Wayne A. Christopher, U. C. Berkeley CAD Group
 #include "ngspice/ngspice.h"
 #include "ngspice/cpdefs.h"
 #include "ngspice/dvec.h"
+#include "ngspice/randnumb.h"
 
 #include "cmath.h"
 #include "cmath2.h"
 
 
-extern void checkseed(void); /* seed random or set by 'set rndseed=value'*/
-extern double drand(void);  /* from randnumb.c */
-extern double gauss0(void);  /* from randnumb.c */
-extern int poisson(double);  /* from randnumb.c */
-extern double exprand(double);  /* from randnumb.c */
-
-
 static double
 cx_max_local(void *data, short int type, int length)
 {
diff --git a/src/maths/misc/randnumb.c b/src/maths/misc/randnumb.c
index bc7433cb4..5daad2094 100644
--- a/src/maths/misc/randnumb.c
+++ b/src/maths/misc/randnumb.c
@@ -39,6 +39,7 @@ Copyright 2008 Holger Vogt
 #include "ngspice/ngspice.h"
 #include "ngspice/cpdefs.h"
 #include "ngspice/ftedefs.h"
+#include "ngspice/randnumb.h"
 #include <math.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -62,15 +63,8 @@ static unsigned LGCS(unsigned *state, unsigned A1, unsigned A2);
 
 double CombLCGTaus(void);
 float  CombLCGTaus2(void);
-unsigned int CombLCGTausInt(void);
-unsigned int CombLCGTausInt2(void);
-double exprand(double);
 
-void checkseed(void);
-double drand(void);
-double gauss0(void);
 void rgauss(double* py1, double* py2);
-int poisson(double);
 
 
 /* Check if a seed has been set by the command 'set rndseed=value'
diff --git a/src/sharedspice.c b/src/sharedspice.c
index 0e9490ea4..77c0a5824 100644
--- a/src/sharedspice.c
+++ b/src/sharedspice.c
@@ -60,6 +60,7 @@ myfputc(int inp, FILE* f)
 
 #include "ngspice/ngspice.h"
 #include "misc/misc_time.h"
+#include "ngspice/randnumb.h"
 
 /*Use Windows threads if on W32 without pthreads*/
 #ifndef HAVE_LIBPTHREAD
@@ -170,7 +171,6 @@ extern void DevInit(void);
 extern int SIMinit(IFfrontEnd *frontEnd, IFsimulator **simulator);
 extern wordlist *cp_varwl(struct variable *var);
 extern void create_circbyline(char *line);
-extern void initw(void);
 
 
 /*The current run (to get variable names, etc)*/
diff --git a/src/tclspice.c b/src/tclspice.c
index b34e3b3c5..eea9c3d62 100644
--- a/src/tclspice.c
+++ b/src/tclspice.c
@@ -26,6 +26,7 @@
 /**********************************************************************/
 
 #include "ngspice/ngspice.h"
+#include "ngspice/randnumb.h"
 #include "misc/misc_time.h"
 #include <tcl.h>
 
diff --git a/visualc/sharedspice.vcxproj b/visualc/sharedspice.vcxproj
index cd1e2b954..9a40cd957 100644
--- a/visualc/sharedspice.vcxproj
+++ b/visualc/sharedspice.vcxproj
@@ -398,6 +398,7 @@
     <ClInclude Include="..\src\include\ngspice\profile.h" />
     <ClInclude Include="..\src\include\ngspice\pssdefs.h" />
     <ClInclude Include="..\src\include\ngspice\pzdefs.h" />
+    <ClInclude Include="..\src\include\ngspice\randnumb.h" />
     <ClInclude Include="..\src\include\ngspice\sen2defs.h" />
     <ClInclude Include="..\src\include\ngspice\sensdefs.h" />
     <ClInclude Include="..\src\include\ngspice\sensgen.h" />
diff --git a/visualc/vngspice-fftw.vcxproj b/visualc/vngspice-fftw.vcxproj
index 42f1425ea..b4517fa76 100644
--- a/visualc/vngspice-fftw.vcxproj
+++ b/visualc/vngspice-fftw.vcxproj
@@ -1015,6 +1015,7 @@ lib /machine:x64 /def:..\..\fftw-3.3.4-dll64\libfftw3-3.def /out:$(IntDir)libfft
     <ClInclude Include="..\src\include\ngspice\profile.h" />
     <ClInclude Include="..\src\include\ngspice\pssdefs.h" />
     <ClInclude Include="..\src\include\ngspice\pzdefs.h" />
+    <ClInclude Include="..\src\include\ngspice\randnumb.h" />
     <ClInclude Include="..\src\include\ngspice\sen2defs.h" />
     <ClInclude Include="..\src\include\ngspice\sensdefs.h" />
     <ClInclude Include="..\src\include\ngspice\sensgen.h" />
diff --git a/visualc/vngspice.vcxproj b/visualc/vngspice.vcxproj
index 9f2c9b403..f8b777083 100644
--- a/visualc/vngspice.vcxproj
+++ b/visualc/vngspice.vcxproj
@@ -981,6 +981,7 @@
     <ClInclude Include="..\src\include\ngspice\profile.h" />
     <ClInclude Include="..\src\include\ngspice\pssdefs.h" />
     <ClInclude Include="..\src\include\ngspice\pzdefs.h" />
+    <ClInclude Include="..\src\include\ngspice\randnumb.h" />
     <ClInclude Include="..\src\include\ngspice\sen2defs.h" />
     <ClInclude Include="..\src\include\ngspice\sensdefs.h" />
     <ClInclude Include="..\src\include\ngspice\sensgen.h" />