Is retractable Antenna repairable?

["Will Hartje" <WHartje@xxxxxxxxxxx>]

When I acquired my 90 325i the radio antenna was bent and the wiring from
the battery was unplugged.
I plugged it back in and found that the motor worked. I have now got a new
mast which I successfully installed and it appeared to work fine.
 Now after just one day it has stopped working and on testing the board, I
discovered it is now only putting 1.7 volts out to the motor at activation
though the activation time (about 12 secs) seems to be correct. Is their any
way to troubleshoot and repair the board or is it possible to get a
replacement board? The model is a Hirschmann Auta 6000 EL  the board has a
part no on it of 721 981 001
Any info appreciated
Regards,
Will Hartje

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