diff --git a/src/mame/drivers/r2dtank.cpp b/src/mame/drivers/r2dtank.cpp
index 7714c7d9f44..ac381a1e4a0 100644
--- a/src/mame/drivers/r2dtank.cpp
+++ b/src/mame/drivers/r2dtank.cpp
@@ -30,6 +30,9 @@ other = M5L8226 (x2)
 RAM = 4116 (x11)
 
 ----------------------------------------------------
+
+XTAL values appear to be 3579.545 (X1) and 11.200 (X2).
+
 ********************************************************************/
 
 #include "emu.h"
@@ -49,7 +52,7 @@ RAM = 4116 (x11)
 
 #define LOG_AUDIO_COMM  (0)
 
-#define MAIN_CPU_MASTER_CLOCK   (11200000)
+#define MAIN_CPU_MASTER_CLOCK   (11.2_MHz_XTAL)
 #define PIXEL_CLOCK             (MAIN_CPU_MASTER_CLOCK / 2)
 #define CRTC_CLOCK              (MAIN_CPU_MASTER_CLOCK / 16)
 
@@ -443,17 +446,17 @@ INPUT_PORTS_END
  *************************************/
 
 MACHINE_CONFIG_START(r2dtank_state::r2dtank)
-	MCFG_DEVICE_ADD("maincpu", M6809,3000000)       /* ?? too fast ? */
+	MCFG_DEVICE_ADD("maincpu", MC6809, MAIN_CPU_MASTER_CLOCK / 4) // divider guessed
 	MCFG_DEVICE_PROGRAM_MAP(r2dtank_main_map)
 
-	MCFG_DEVICE_ADD("audiocpu", M6802,3000000)         /* ?? */
+	MCFG_DEVICE_ADD("audiocpu", M6802, 3.579545_MHz_XTAL)
 	MCFG_DEVICE_PROGRAM_MAP(r2dtank_audio_map)
 
 	NVRAM(config, "nvram", nvram_device::DEFAULT_ALL_0);
 
 	/* video hardware */
 	MCFG_SCREEN_ADD("screen", RASTER)
-	MCFG_SCREEN_RAW_PARAMS(PIXEL_CLOCK, 256, 0, 256, 256, 0, 256)   /* temporary, CRTC will configure screen */
+	MCFG_SCREEN_RAW_PARAMS(PIXEL_CLOCK, 360, 0, 256, 276, 0, 224)
 	MCFG_SCREEN_UPDATE_DEVICE("crtc", mc6845_device, screen_update)
 
 	PALETTE(config, m_palette, palette_device::BGR_3BIT);
@@ -496,11 +499,11 @@ MACHINE_CONFIG_START(r2dtank_state::r2dtank)
 	GENERIC_LATCH_8(config, m_soundlatch);
 	GENERIC_LATCH_8(config, m_soundlatch2);
 
-	AY8910(config, m_ay1, (4000000 / 4));
+	AY8910(config, m_ay1, 3.579545_MHz_XTAL / 4); // probably E clock from MC6802
 	m_ay1->port_a_read_callback().set_ioport("DSWB");
 	m_ay1->add_route(ALL_OUTPUTS, "mono", 0.25);
 
-	AY8910(config, m_ay2, (4000000 / 4));
+	AY8910(config, m_ay2, 3.579545_MHz_XTAL / 4);
 	m_ay2->port_a_read_callback().set_ioport("IN1");
 	m_ay2->port_b_read_callback().set_ioport("DSWA");
 	m_ay2->add_route(ALL_OUTPUTS, "mono", 0.25);