Exactly George. I'm a little reluctant to put even the 500W TVS diodes in, they're right across the DCS signal, and they exhibit considerable stray capacitance, on the order of 1,000pf. At 3mhz, that's a capacitive reactance of around 50 ohms, that's a significant shunt across the DCS signal.
BTW, according to the Service Bulletin 05-22-18a.pdf, it only applies to the Rev. L units. Is there a newer release that includes the I3A version?
