What exact Blau model you have? Normally, all of the period Blaus had in their rear panel a special power output to feed the power antenna, not need to add any extra switch.
When your wife touches the antenna her body is changing the... hidden antenna's inductance and actually your wife becomes ..an antenna! So, because it is not so convenience to have the wife hanging from the antenna while cornering just try these:
1. find a way to check if the special +12VDC output from the Blau's rear panel really gives the power when you activate the radio, means must give the voltage AFTER you turn on the radio. If not, there is a problem INSIDE the radio. If gives the voltage, see if THERE IS any cable connected with this output. If not use a good multicore wire all the way from there to the antenna.
If yes, there is a wire connected, see first if someone had connected a fuse in the line. Then check the fuse if it is blown.
2. If finally the wire exists till the trunk , go at the trunk and locate that cable and see if the voltage is ok and most of all, if the wire is somehow connected to the antenna's motor ( see also if the above fuse holder is there and not under the dash!).
3. Maybe, the most common and the easiest for you.. Is the antenna's body right grounded? If not, the antenna can not be working anyway! So pick up any wire and ground the antenna body with a good chassis clear metal.
If none of the above will not solve the problem, and although antenna is feeding with the proper voltage but you hear some "tick-tick" noises, buy a new one or a good used power antenna
