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You measured the filter at 50ohm but the terminating impedances should have been 650ohm/3pf. I am not sure whether the impedance of the stock filter is similar and the matching in the Ubitx might be adequate as is.

Il 08/set/2018 03:16, "Warren Allgyer" <allgyer@...> ha scritto:

My filters arrived earlier than expected. These are from eBay at?

Immediate results are disappointing so I have put them on the S/A to see what is going on.

Center frequency: 44.987166 MHz, about 13 kHz lower than expected
Insertion loss: 6-10 dB across the bandpass at 50 ohms in/out
Corner points: 15 kHz across center

This filter is going to play havoc with SSB because of the variance across the filter passband and because 45 MHz is centered on the extreme high side of the filter.?

When I put it in in place of R27 the results were not good. But it is early and I have lots to verify yet. Tomorrow I will pull the 45 MHz filter supplied with the uBitx and check it in the same way. I have no point of reference but I am not excited about these filters at this point in the testing.

WA8TOD