Crystal Filters

[VK3YNV]

Another good video from ZL2CTM

 

[VK3ZYZ]

Bills' Board would be good for this I reckon.

 

[BillC]

Bill has quite a few 1971.20 khz crystals. Bill is on an electronic go slow at the present time. Bill is presently coming down from the stresss of shearing. might try those crystals later on. 1975.20 khz is fairly low for that type of filter and I guess it would be too sharp for SSB , but one trick to widen the response is to parallel two crystals on the input port and two on the output port and perhaps select for a little bit of different resonance for each of those crystals. One could also play around with the loading impedance, hours of fun could be had ! If testing the filter response with the NANOVNA I think we need to reduce the sweep range to just cover the required span so as to obtain more plot points. I think I saw on one video that the presenter was remarking about a less than satisfactory display maybe the sweep range was too wide ?

 

[VK3YNV]

I think I saw on one video that the presenter was remarking about a less than satisfactory display maybe the sweep range was too wide ?

I wondered the same, he might have calibrated over a wider range and that reduces the number of points when you zoom in to a narrow range.