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The laser induced fluorescence spectrum of the red $A2\Pi -X2\Sigma$ system of SrF has been recorded. Typical line widths of 20MHz are obtained with the laser beam crossing the molecular beam orthogonally. Each rotational line of the $\mathrm{<mrow\; data-mjx-texclass="ORD">88</mrow>}SrF$ main isotope and $\mathrm{<mrow\; data-mjx-texclass="ORD">86</mrow>}SrF$ lesser isotope is split into two components by the magnetic hyperfine interaction between the unpaired electron and the $\mathrm{<mrow\; data-mjx-texclass="ORD">19</mrow>}F$ nuclear spin of 1/2. The rotational line assignment of this band was confirmed by the rf labelling method (1), using previously measured ground state splittings (2). In addition, with our excellent S/N ratio, it was possible to record many lines from the much less abundant isotope $\mathrm{<mrow\; data-mjx-texclass="ORD">87</mrow>}SrF$, clearly showing hyperfine structure due to the $\mathrm{<mrow\; data-mjx-texclass="ORD">87</mrow>}Sr$ nuclear spin of 9/2 as well as the hfs due to the $\mathrm{<mrow\; data-mjx-texclass="ORD">19</mrow>}F$ with its spin of 1/2. Efforts to measure the ground state hyperfine splitting of $\mathrm{<mrow\; data-mjx-texclass="ORD">87</mrow>}SrF$ by the rf-laser double resonance method are currently underway.