8 Watt Ku BUC 8dBpp Response

Hi All,

I have an 8W Ku band BUC on my bench (NJT5118), gain and p1dB are good. Response is not......please see attached spectrum analyzer picture. It has about 8dB of variation. Any ideas what could be causing this? I have not seen this much variation in output before. All I can think of right now is component aging, perhaps taking a shotgun approach replacing what is economical and retesting.

Thanks!

Joe