diff --git a/src/mame/drivers/hh_tms1k.cpp b/src/mame/drivers/hh_tms1k.cpp
index dedfe0d717e..21496ce5961 100644
--- a/src/mame/drivers/hh_tms1k.cpp
+++ b/src/mame/drivers/hh_tms1k.cpp
@@ -5042,7 +5042,7 @@ static const INT16 copycat_speaker_levels[4] = { 0, 0x7fff, -0x8000, 0 };
 static MACHINE_CONFIG_START( copycat, copycat_state )
 
 	/* basic machine hardware */
-	MCFG_CPU_ADD("maincpu", TMS1000, 350000) // approximation - RC osc. R=47K, C=47pf
+	MCFG_CPU_ADD("maincpu", TMS1000, 320000) // approximation - RC osc. R=47K, C=47pf
 	MCFG_TMS1XXX_READ_K_CB(READ8(copycat_state, read_k))
 	MCFG_TMS1XXX_WRITE_R_CB(WRITE16(copycat_state, write_r))
 	MCFG_TMS1XXX_WRITE_O_CB(WRITE16(copycat_state, write_o))