If your TM751 is set to House Code A I think it will cycle everytime you change camera's or automatically if you have the multi-cam scan turned on. I many not have used the right terms but when I set mine up the first time I had that issue, so I set the TM751 on a different house code and used a motion to turn it on when then powered the cams set on another house code.
Not sure if that helps...
So do I change the transiever to house code B and leave the cameras on A?
The motion sensor how do you sue it ?
Could have two problems going on here, if your cams are not responding at all to switching, then try some of the things in the other posts before this one, I had that issue also and found that the code I was using "N" (for Ninja) did not seem to be liked for some reason, so I changed it to another code and life was good. That out of the way, I moved to how to trigger them.
Now assuming that you can address the cams and they work, the way to use the motions is just to turn on the program the motion detector to send the On code for the cam that would be in range of the motion that got triggered. So if if the EagleEye that "sees" motion for Cam1 on then I setthat EagelEye to Send a C1 On and set the delay for 8 minutes (how to do this is in the instructions for the motion detector.
Otherwise there are any number of ways to trigger them through AHP, set it to scan all your cams and it will cycle thrgough them C1, C2, C3... or what ever codes you picked. In AHP you can simple set a Cam On/Off control that you click on, and of course you can use and X-10 remote that sends RF X10 On/Off commands (except the security remote) to turn them on and off. I also control my Video Commander this way, that is why I have the 8 minute delay, the commander will direct your recorder to record for 5 minutes (no more, no less) when trigggered. I picked 8 miniutes for the Motion Off delay time because the options are 1, 2, 4, 8, 16,... minutes, so 8 works well since if it is triggered again after the first 5 minutes the cam is still powered up.
Hope this helps.