Scott,
You wrote;
'It would be better if the coupler had a -50 dB coupling factor, then the answer would be -3.6 dB, which is close enough to optimum.'

Can you tell me what the optimum would be (instead off -3,6 dB) ?
Then i can calculate what the coupler factor has to be and change that.

When I do the math I need a -8,586 dB (so no ATT) Is this right?

(Calculation with: 1100 Watt, coupler -55 dB)
Step 1: 10Log (1100 W) + 30 = 30,414+30 = 60,414 dBm
Step 2: 60,414 dBm (from step1) - 55 dB (RF2KS sampler) = 5,414 dBm
Step 3: -11 dBm (Anan7000) + 25 dB = 14 dBm
Step 4: 5,414 dBm ...

Solved
Tried different computers, firewall check was ok, no updates on any devices. The problem was that someone who was visiting and wanted to work here with a laptop got the same DHCP IP-address of the Anan. Assigned a static IP-address to the Anan and all was solved. Thanks everyone

As of today my Anan 7000DLE Mk2 (black facing) won't suddenly connect anymore to Thetis.
Yesterday (and all years before) it worked fine. Nothing has changed since yesterday i shut down thetis.
Now i start Thetis, it seems like a connection to the Anan and after 1 second 'lost radio sync' is ...