I checked the RF levels at the LSC LO distribution box, with the agilent scope and a handful of couplers. This was all done with the Marconi at +13dBm.
I only checked the channels that are currently in use, since the analyzer only measures 3 channels at a time, and rewiring involves walking back and forth to the IOO rack to make sure unpowered amps aren't driven, and I was getting hungry.
For the most part, the LO levels coming into the LSC demod boards are all around +1.5dBm (i.e. I measured around -18.0dBm out of the ZFDC-20-5 coupler, which has a nominal 19.5dB coupling factor)
The inputs piped over from the IOO rack, labeled as "+6dBm" were found to be 4.7dBm and 2.9dBm for 11Mhz and 55MHz, respectively.
The 2F signals were generally about 40dB lower, with two exceptions:
- REFL165's ~332MHz signal was around -18dBc
- POP22 had many more visible harmonics than any other LO signal
- 11MHz: -32 dBc
- 33MHz: -32 dBc
- 44Mhz: -15dBc
Here are the raw numbers I measured out of the couplers, all in dBm:
11MHz in: -14.8
55MHz in: -16.6
POX11: -18.7
POY11: -18.0
REFL11: -18.0
REFL33: -18.3
POP110: -17.9
AS110: -18.1
POP22: -19.9
REFL165: -18.5
AS55: -18.6
POP55: -18.8 (this port is used as the REFL55 LO)
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