SUBROUTINE REGMOD ( )

Description
THIS ROUTINE FINDS ALL MODES FOR THE CURRENT FREQUENCY AND THE 
DISTANCE FROM THE IONOGRAM (NO SPORADIC E MODES - SEE SUBROUTINE 
ESMOD) THIS IS FOR A GIVEN HOP DISTANCE SET IN SUBROUTINE LUFFY
Source file:regmod.f
I/O Operations:
Unit ID  Unit No       Access  Form   Operation
               99         SEQ  FMTD           W  

Operation codes A=rewind,B=backspace,C=close,E=endfile
                I=inquire,O=open,R=read,W=write
Intrinsic Functions Called
INTEGER            IAND
REAL               ALOG,       ALOG10,     AMAX1,      AMIN1
GENERIC            ABS,        ATAN,       COS,        EXP
GENERIC            SIN,        SQRT
External Functions and Subroutines Called
REAL               PRBMUF,     PWRDB
SUBROUTINE         GAIN
Local Variables (+ indicates altered content)
INTEGER           +IG,        +IGX,       +IHOP,      +IM
INTEGER           +ISMOD,     +ITRY,      +K,         +L
INTEGER           +LX(3)
REAL              +AC,        +ADX,       +BC,        +BCX
REAL              +CDEL,      +CPHET,     +CPR,       +CPSI
REAL              +DEL,       +DUMMY,      DUMMY1,     DUMMY2
REAL              +ESD,       +FMHZ,      +FSDEAD,    +FVFOT
REAL              +FVHPF,      GEFF,      +GHLOS,     +HEFF
REAL              +HNUX,      +HOP,       +HOPS,      +OBFL
REAL              +OBFU,      +P,         +PATH,      +PF
REAL              +PHE,       +PROS,      +PSI,       +SECP
REAL              +SECS,      +SINP,      +SINS,      +SPHE
REAL              +SPHET,     +SPSI,      +TANP,       TEFF
REAL              +XFAC,      +XKM,       +XLS,       +XLSL
REAL              +XLSLWO,    +XLSU,      +XLSUWO,    +XLSWO
REAL              +XMUF,      +XNSQ,      +XRAT,      +XTLOS
REAL              +XV,        +Y,          YG
Referenced Common Block Variables (+ indicates altered content)
ANOIS              REAL               RCNSE
CON                REAL               D2R,       PIO2
CON                REAL               RZ,        VOFL
DON                REAL               GCD
ES                 REAL               FS(3,5),   HS(5)
FRQ                INTEGER            JMODE
FRQ                REAL               FREQ
GEOG               REAL               GYZ(5)
INFORM             INTEGER            INFO
MODES              INTEGER            ITMOD(6,3)
MODES              REAL               AFMOD(6,3)
MODES              REAL               DELMOD(6,3)
MODES              REAL               FVMOD(6,3)
MODES              REAL               GHOP,      HPMOD(6,3)
MODES              REAL               HTMOD(6,3)
MUFS               REAL               FVMUF(4),  HPMUF(4)
MUFS               REAL               HTMUF(4),  YFOT(4)
MUFS               REAL               YHPF(4),   YMUF(4)
RAYS               INTEGER            IFOB(40,30,5)
RON                INTEGER            KM
RON                REAL               FI(3,5)
SIGD               REAL               ACAV,      AFE
SIGD               REAL               ASM,       BFE
SIGD               REAL               DSL,       DSU
SIGD               REAL               HNU,       HTLOSS
SIGD               REAL               XNUZ,      XVE
ZON                INTEGER           +NMODE(7)
ZON                REAL              +ABPS(7),  +ADV(7)
ZON                REAL              +B(7),     +EFF(7)
ZON                REAL              +FLDST(7), +FSLOS(7)
ZON                REAL              +GRLOS(7), +HN(7)
ZON                REAL              +HP(7),    +OBF(7)
ZON                REAL              +PROB(7),  +RGAIN(7)
ZON                REAL              +SIGPOW(7)
ZON                REAL              +SN(7),    +TGAIN(7)
ZON                REAL              +TIMED(7), +TLHGH(7)
ZON                REAL              +TLLOW(7), +TLOSS(7)