pro INT_ORD,dir,Receiver,SUN,P,Nord,Ord,Chan,Radio=Radio

;+
;	INPUT ARGUMENTS:
;
; dir - direction (0 - E-W, 1 - S-N);
; Receiver - Type of the SSRT receiver used: 0 - MFB, 1 - AOR;
; SUN - structure SOL_EPHEMERIDE issued by the procedure
; SUNEPH.
;
;	OUTPUT VALUES:
; P - 3-elementary floating-point, double precision array composed
; from the angles between interferometer's base and one edge of
; the Sun; centre of the Sun; other edge of the Sun, respectively.
; This angle is measured from the Western direction for the
; E-W interferometer, and from the Southern direction for the
; S-N interferometer.
;-

	if n_elements(Radio) le 0 then Radio=1.08;1.175

D=4.9D0	&	C=2.997925D8	&	Fi=51.7575D0*!DPi/180

	Sum_chan=[180,192]

Bound_Frequencies=chanfreq([1,Sum_chan(Receiver)],Receiver)

Fmin=Bound_Frequencies(0)
Fmax=Bound_Frequencies(1)

Ord=intarr(4)

     IF dir eq 0 then P=acos(sin(SUN.H)*cos(SUN.Decl)) else $
P=acos(cos(SUN.H)*cos(SUN.Decl)*sin(Fi)-sin(SUN.Decl)*cos(Fi))

dP=Radio*SUN.R*((1-dir)*sign(SUN.H)+dir)
P=[P-dP,P,P+dP]

Ordmin=Fmin*D*Cos(P(2))/C
Ordmax=Fmax*D*Cos(P(0))/C

	Ord(0)=fix(Ordmin+((1-dir)*sign(SUN.H)+dir))

		Nord=0

		for i=0,2 do begin
	if(abs(Ord(0))+i LE abs(Ordmax)) then begin
Nord=i+1
Ord(i+1)=Ord(i)+((1-dir)*sign(SUN.H)+dir)
	endif
		endfor

Nord=Nord > 1

Ord=Ord(0:Nord-1)

Chan=chanfreq((C/(D*cos(P))#Ord),Receiver)

			end