diff --git a/bts/BTS_Tests_LAPDm.ttcn b/bts/BTS_Tests_LAPDm.ttcn
index 0c032bb..a4fa2e8 100644
--- a/bts/BTS_Tests_LAPDm.ttcn
+++ b/bts/BTS_Tests_LAPDm.ttcn
@@ -43,16 +43,18 @@
 
 /* master function switching to a dedicated radio channel */
 function f_switch_dcch() runs on ConnHdlr {
-	var GsmBandArfcn arfcn := valueof(ts_GsmBandArfcn(mp_trx0_arfcn));
+	var GsmBandArfcn arfcn := valueof(ts_GsmBandArfcn(mp_trx_pars[0].arfcn));
 	var BCCH_tune_req tune_req := { arfcn := arfcn, combined_ccch := true };
 	var DCCH_switch_req sw_req;
 
 	/* Craft channel description (with or without frequency hopping parameters) */
 	if (g_pars.fhp.enabled) {
-		sw_req.chan_desc := valueof(ts_ChanDescH1(g_pars.chan_nr, g_pars.fhp.maio_hsn));
+		sw_req.chan_desc := valueof(ts_ChanDescH1(g_pars.chan_nr,
+							  g_pars.fhp.maio_hsn));
 		sw_req.ma := g_pars.fhp.ma;
 	} else {
-		sw_req.chan_desc := valueof(ts_ChanDescH0(g_pars.chan_nr, mp_trx0_arfcn));
+		sw_req.chan_desc := valueof(ts_ChanDescH0(g_pars.chan_nr,
+							  mp_trx_pars[0].arfcn));
 		sw_req.ma := omit;
 	}