Today I checked the RF level at various points in the ISC R3 rack (which is the one by HAM6, containing the AS-related demodulators) as a part of the DRMI preparation.

The next thing we need to in this rack is the I-Q balance adjustment for all the demodulators. This is something we can do before the table is moved in place.

RF level re-adjusted:

I have adjusted the RF level by inserting or changing RF attenuators such that the power at the input of every RF device is at 10 dBm except for the WFS quad demodulators. Sine those quad demodulators have a 4-way splitter in the box, they did not have to be as low as 10 dBm. So I simply did not put an attenuator for their paths. This gave me about 13 dBm at the inputs of all the quad demodulators.

Two RF cables replaced:

When I was checking the RF level, I found two wacky cables which showed anomalously high loss. One of them was pretty obvious -- the SMA connector part was the cause and stress on the connector changed the amount of the loss. So I simply cut the SMA connector part off of the cable and put a new SMA connector. This fixed the issue. In the other cable, I could not identify what parts were giving the high loss. However Filberto replaced both N-connector and SMA connector for me and this fixed the issue. I put them back in the rack and confirmed that the RF levels were at the expected level. Good.