The EVN correlator has 32 correlator boards, each of which can currently
handle a total of 4096 lags. The number of frequency points you will see
is half the number of lags used in the correlation, so there is a total number
of 65536 frequency points (
).
This capacity must be
divided among all the individual baseline/subband/polarization interferometers
that belong to your experiment. The relevant formula is:

(4) 
You can use eq.(4) to find
the maximum number of frequency points
you can get per baseline/subband/polarization product. However, due to the
specifics of how the correlator is configured, there are some factors to
keep in mind:
 can only be a power of 2.
 Minimum value is 16.
 Maximum value is 2048 (a baseline/subband/polarization product
must fit onto a single correlator board).
 can only be 1, 2, or 4 (of course, can be
2 or 4 only if you scheduled a dualpol experiment).
 The product of and
must be .

must be a multiple of 4, such that
, your actual number of stations (hence its different
font in eq.(4) to draw attention to this subtlety).
 If
, then we have to correlate your experiment
in multiple passes. If
(3 passes required),
then use
when determining
the
to use in eq.(4).
 Note that if all other parameters are powers of 2,
then networks from 916 stations will all have the same maximum .
Thus, for example, dropping from
would gain you a factor
of 4 in maximum , all other parameters remaining constant.
Table 1 summarizes some valid configurations that use the
whole correlator.
Table 1:
Some
configurations
that use the whole correlator.

16sta 
1SB 
1Pol 
512Frq 
(Max. for 16 stations) 

8sta 
1SB 
1Pol 
2048Frq 
(Max. for 8 stations; also current max. possible ) 

4sta 
2SB 
2Pol 
2048Frq 
(with only 4 stations, you can get more SB/Pol) 

16sta 
8SB 
4Pol 
16Frq 
(opposite extremes: many SB/Pol with low ) 

8sta 
16SB 
4Pol 
32Frq 


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