Copy Beta tape to VHS?

I am trying to copy some old home beta movies to vhs and am not being too successfull. I have connected with coax the sony beta output to the vhs input and then from the vhs output to TV. The beta movie will play on the TV but when I power up the vhs and try to copy the TV screen loses the picture. I then shut off the beta and rewound the vhs and tried to see if it would play the copied tape but it just came up blank. I have tried 3 different VHS's and the same result.Also the vhs tapes were good for copying and I could also play store VHS movies to the TV. I have also tried a splitter on the beta outlet to feed the TV and vhs at the same time and still will not work. I also tried using rca cables in place of the coax and still no go. The beta is a sony hifi and has 2 audio and one video so I just connect 1 audio line. I am going bald with this. Please help if you have any ideas.
Thanks