In order to bring HB-100 radar modules into the 10 GHz HAM allocation, their frequency has to be reduced. Reports say that the stock screw is enough, better if replaced with one with finer thread.
Then I investigated how Dielectric Resonator Oscillators work (wikipedia, no more no less) and tried few simulatons with the provided formula: the more dielectric material, the lower the frequency.
So, assuming that we have some "extra" dielectric laying around, like from a similar (dead) module, it could be worth trying to add it on top and see the resulting frequency. Besides providing a sort-of fixed frequency, it would reduce the number of factors that are influended by temperature and cause frequency instability.
For first experiments I will stick to the screw method. Reports of success/failure are welcome.