diff --git a/bts/BTS_Tests.ttcn b/bts/BTS_Tests.ttcn
index dfda043..8a9e24a 100644
--- a/bts/BTS_Tests.ttcn
+++ b/bts/BTS_Tests.ttcn
@@ -545,13 +545,21 @@
 		}
 
 		if (ispresent(pars.maio_hsn)) {
-			/* Compose the Mobile Allocation */
+			/* Prepare the Mobile Allocation bitmask (length & padding) */
+			pars.ma_map.len := mp_transceiver_num / 8;
+			if (mp_transceiver_num mod 8 > 0)
+				{ pars.ma_map.len := pars.ma_map.len + 1; }
+			pars.ma_map.ma := f_pad_bit('0'B, pars.ma_map.len * 8, '0'B);
+
+			/* Compose the actual Mobile Allocation and the bitmask */
 			for (j := 0; j < lengthof(g.trx_maio); j := j + 1) {
 				var FreqHopGroupItem gi := g.trx_maio[j];
 				pars.ma := pars.ma & { l1ctl_ma_def[gi.trx_nr] };
+				pars.ma_map.ma[gi.trx_nr] := '1'B;
 			}
 
-			log("Freq. hopping parameters: ", pars.maio_hsn, pars.ma);
+			log("Freq. hopping parameters: maio_hsn := ", pars.maio_hsn,
+			    ", ma := ", pars.ma, ", ma_map := ", pars.ma_map);
 			break; /* We're done */
 		}
 	}