Dyorel, I don't think frequency is going to play any role: in a rectifier circuit, it makes no diff whether the AC is on 50Hz or 100Hz.
Neonazure - what does your adapter say about input?
If its switched mode unit - then it has the ability to take in vast variation in voltage. Switched mode units don't operate like regular step down transformers + rectifiers.
Examples of switched mode = Computer power supply, mobile rechargers, laptop rechargers - all are small sized and can take in a wide variation of volatage like 110 to 250 V.
You donít get what you deserve, you get what you negotiate.