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continuing our ongoing project aimed at the search and analysis of pulsating stars in globular clusters ( see ( * ? ? ?
* kopacki 2013 ) ) we present preliminary results for ngc 4833 .
we used image subtraction method ( ism , ( * ? ? ?
* alard &  lupton 1998 ) ) which works well in crowded stellar fields like a cluster core and thus enables detection of many variable stars , such as rr lyrae and sx phoenicis stars .
ngc 4833 is the southern globular cluster of intermediate metallicity ( [ fe / h]@xmath01.85 ) .
the most recent version of the catalogue of variable stars in globular clusters ( cvsgc , ( * ? ? ?
* clement et al .  2001 ) ) listed 34 objects in the field of this cluster including six sx phoenicis stars and 20 rr lyrae stars .
we used ccd observations obtained during one - month observing run in feb / apr , 2008 using 40-inch telescope at siding spring observatory , australia .
they consisted of 740 @xmath1-filter and 220 @xmath2-filter ccd frames .
we confirmed all variable stars found recently in the cluster core by ( * ? ? ?
* darragh &  murphy ( 2012 ) ) .
in addition , we have detected two new sx phoenicis stars , one new rr lyrae star , twelve new eclipsing systems mostly of the w ursae majoris type , nine new variable red giants at the tip of the rgb , and ten field - stars showing irregular variations .
equatorial coordinates of periodic variable stars we observed , together with derived periods , are given in table [ tab1 ] .
new variable stars are indicated with designations starting with letter n.    the mean period of rrab stars in ngc 4833 is equal to @xmath30.701 d , and relative percentage of rrc stars amounts to @xmath448 % . with these values
we find that ngc 4833 belongs to the oosterhoff s ii group of globular clusters .
almost all observed sx phoenicis stars show multiperiodic light changes ( see table [ tab1 ] ) with one star , v31 , exhibiting oscillation in two first radial modes .
moreover , we found in an rrc star v20 two closely - spaced frequencies .
we present preliminary results of the variability survey in the field of the globular cluster ngc 4833 . 
 we observed all 34 variable stars known in the cluster . 
 in addition , we have found two new sx phoenicis stars , one new rr lyrae star , twelve new eclipsing systems mostly of the w ursae majoris type , nine new variable red giants , and ten new field - stars showing irregular variations . 
 properties of rr lyrae stars indicate that ngc 4833 is an oosterhoff s type ii globular cluster .