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Hi it seems to me that for a linear or quasi-linear circuit without active elements, it should be correctly compensated by single precision floating point calculation using the Z renormalization

Since most filters are a series of resonators of some kind or another, terminating them in a resistance other than the design resistance will probably change the filter characteristics. Consider a

Here is an article on ceramic filters by a popular manufacturer Murata. https://www.changpuak.ch/electronics/ceramic_filters/Murata_piezo_filters.pdf Attached is an excerpt showing the importance of

Hi John and gang, I decided to keep things relatively simple and just used my signal generator with matching transformer to feed the ceramic filter and then compared response using either a 56 ohm

Hi Mike, Insertion loss and bandwidth measurements nearly identical between the l pad matching system versus using transformers which thankfully is what should have happened. The transformers which

Hi Don, Missed it. How to the response curves compare? Mike N2MS

Hi Mike, Not sure you saw my most recent post as I switched to transforms earlier today to improve my dynamic range and posted pictures of the results. Don

Don, I use construct resistive minimum loss attenuators for this application but keep in mind the attenuation decreases the dynamic range of the measurement. Mike N2MS

Sorry, here are the attachments per my previous post. Don

Hi John, As Nizar mentioned renormalization is not available on my NanoVNA which is the NanoVNA-F. This morning I decided to improve my measurement dynamic range so I replaced my L pad matching

Don, I didn't do that for this test, but at some point in the past I did all that. I had unknown crystal filters and used the NanoVNA renormalization to find the Z that gave the best looking

Hi Donald I think what you have done physically with your Deeplec Nano-F is almost what is done by jhon but with H4 and z port renormalisation and physically cute & short connection with optimised

Hi John, I'm a little late to the party but this topic peaked my interest and my thinking is very much aligned with Rogers. I think the one comparison test you are missing is what filter response

To measure insertion loss, you connect the channel 1 to the common port of the diplexor and channel 2 to one of the output ports while terminating the unused port with a 50 Ohm load. Move channel 2 to

Hi Joe You seems need an S21 Logmag measurement , Knowing that dynamic range of H4 on the UHF are limited to 50db you should not expect more then -45db values for the isolation measurements between

I have a NanoVNA-H4, I have no problems checking antenna SWR etc. But what I want to do now is to check the performance of a "Diplexor" You know one of these things that splits/combines a 2 meter

Hi May be not a very objective vision, it seems to mee that there is a little confusion in vision between 0 and 8 on the display, with SEESII H4 + DiSlord 1.2.40 , I prefer a simple 0 graphic

Hi PY2CSH For me per example , I prefer set Z port 1 to 75 Ohm virtually and keep Z port 2 to 50 Ohm as it's physically , so it can be very handy option for who need it . 73's Nizar

? ... I personally don't see the need to have different Z for the input and output of a DUT. ... ? How about a matching network, say matching 50 to 20 ohms?

Roger, You are correct. There is no added matching circuitry. It's all math. The physical connections are the same for both plots. --John