*8657B Specifications:

Frequency Range : 100kHz - 2.06GHz
Frequency Resolution : 1Hz
Output Accuracy : +/- 1.5dB - +/- 1.0dB
Output Range : -143.5dBm - +13dBm
Output Resolution : 0.1dB
SSB Phase Noise Range : -136dBc - -118dBc