I don't promise this will work, but if you are trying to turn on or adjust the RF modulator channel, you could try this..
1) First switch VCR into standby.
2) Press and hold down the Power button for 5 seconds.
RF Channel will appear in the VCR's display.
3) Adjust RF Output with CH up/down buttons.
I don't know your specific model but the above seems to apply to several Matsui models.
Cobweb, February 2007