The mole shock: sense or nonsense a matter of strategy?

I live right on the edge of the field and am therefore literally plagued by Mauwürfen that my garden probably more than appreciate their agronomically used old home.
Looking for solutions, I'm on this "mole Schreck's" hit and was initially confused by positive and negative Reressionen who best keep product regardless the scale.
Lack easy I bought this mole fright pair nevertheless realizable alternatives, trial does indeed wise.

Have the two devices placed between the maulwurfzerfurchte area and house and waited tensely. All the same, one of the devices sounds more like an old ship Foghorn That others like ne cheap electric doorbell. For some acoustic alternation was so worried. This has the moles or the mole but not disturbed, the manager or simply dug unimpressed.

After 2 weeks of success, it was time to rethink strategy towards "step forward" and "all or nothing":
I bought three more units, all different and the unit price of 15 euros max. Thus I had a repäsentativen product cross section of solar and battery-powered sound bars at the start and almost 60 euros less on the account.

After commissioning of all 5 units sounded impressively on my mole home to about 20 x 6 m. Day and night, with different tones and frequencies. After 2 days I have the entire area glattgeharkt to aim for the position.
And then: No more hills! One of the devices I have since been removed due to demands of interested neighborhood that sounded beyond all others. But was not this couple. The rest remains a precaution put first and where grass has grown back over it, the collection will be presented to the mole-ridden neighborhood.
So at least the plan.

Conclusion: Which of the devices is the best and most successful, I do not know. Think of it simply as a team victory.
This device couples has probably contributed to the success, winning alone could not with me.

I have to correct my rating down:
A device is defective, around second digging a mole, -)
Rate from from purchase.