Kerry Wong did a teardown of a Wavetek 1045 RF power meter:
I bought a Wavetek 1045 RF power meter off eBay a few weeks ago. It came with a 13787 detector which is capable of measuring RF power between -50 dBm to 10 dBm with a frequency range of 1 MHz to 18 GHz.
Compared to the ubiquitous HP 436A, which I did a teardown of a while ago, the Wavetek 1045 was from roughly the same era (late 70’s to late 80’s). Although this unit was made in the late 1980s which is about 5 years later than the manufacture date of my HP 436A.
Unlike the 436A, which uses a thermal couple as the sensing element in the RF power head, the Wavetek 1045 uses a Schottky diode based design. The 13787 detector is a single diode detector. There are also balanced (dual diode) detectors available (e.g. 15177), which offer 6 dB higher dynamic range and better measurement accuracy.