(Fil, Mani, Daniel)

Adding the 10 MHz frequency reference to the RF synthesizer in the mechanical room turned out to be more involved than we planned. First, we noticed that some of the RF distribution cables were badly terminated and needed to be redone. We then found that no baluns were added—generating one big ground loop through the RF cabling.

This is the current setup:

• An RF patch panel from our stock has been added to the TCS rack in the mechanical room.
• The 10 MHz signal is routed to the mechanical room where the RF synthesizer uses it as an external reference. A balun has been added in the mechanical room.
• The RF synthesizer runs at 40.68 MHz and 13 dBm output on the N connector.
• The output of the RF synthesizer terminates in the TCS-R1 rack. A balun and an attenuator has been added at the R1 end. This signal is routed to the distribution amplifier.
• We used a free output of the distribution amplifier and routed the signal back to the CER. There we added yet another balun and routed the signal to the timing comparator/frequency counter. Channel 3 now reads back the TCS AOM frequency in Hz.

We noticed that thin coax cables were used to route the RF signals from R1 to R2. We should replace those with the proper thick coax which is used everywhere else in the distribution system.

We still need to route a DB25 cable from the RF distribution amplifier to the RF amp concentrator in the CER. This way we have both frequency and RF power readbacks available. The EtherCAT system was udated with the new monitor channels for the TCS RF distribution amp. This will make it straight forward to diagnose a problem with this RF synthesizer.

A new medm screen was made for the TCS RF distribution (see attached).