C RARCOX: exec phase of /RISCARCO 
C-----------------------------------------------------------------------
C PURPOSE:  take risc ARCO trace defined at SR=4, convert to SR=2,
c	then resample back to SR=4 but with back zero-padding.
C-----------------------------------------------------------------------
C WINDOW ARGUMENTS:
C NAME    TYP  DIM  IO  DESCRIPTION
C ------  ---  ---  --  -----------
C
C-----------------------------------------------------------------------
C COMMON ARGUMENTS:
C NAME    TYP  DIM  IO  INCLUDE  DESCRIPTION
C ------  ---  ---  --  -------  -----------
C
C-----------------------------------------------------------------------
C PROGRAM HISTORY:
C NAME  DDMMMYY  DESCRIPTION
C ----  -------  -----------
C DAO   25jan90  initial installment
c dao	05mar92	 install into IRIS-SEIS v1.5
c dao	12mar92	 modified from /EASYADD's EASYIN.f and EASYEX.f
c dao	29jul92	 installed
C Copyright (c) none
C All Rights Reserved.
C-----------------------------------------------------------------------
      SUBROUTINE RARCOX (JP, TRACE, WORK)

c#include "SSCOM.INC"
c#include "SSCUNI.INC"
	include "SSCOM.INC"
	include "SSCUNI.INC"
      INTEGER   JP
      REAL      TRACE(1), WORK(1)


c check instrument type using GCV 
	if(KTRWGT .ne. 1)goto9000

c have ARCO trace

c trace(1) at 0 msec
c now save every other sample
	do it=3,KNSAMP,2
		itnew=(it+1)/2
		trace(itnew)=trace(it)
	enddo
	itnew=(KNSAMP+1)/2
	do it=itnew+1,KNSAMP
		trace(it)=0.
	enddo

c is there a TDELAY?
c TDELAY stored in KMSFDS in msec
	if(KMSFDS.eq.0)goto9000
	nt4delay=KMSFDS/4
	do it=itnew,1,-1
		trace(it+nt4delay-1)=trace(it)
	enddo
	do it=1,nt4delay-1
		trace(it)=0.
	enddo


c SR was 4 coming, leave at 4 going out
c	SR=.004
	

 9000 RETURN
      END