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I'm following this with great interest as this is something that I'm also busy learning about while waiting for my NanoVNA-H4 - thanks for all the valuable info so far!

Hi all I bought what I believe is the nanoVNC-h on fleepay. 50kHz - 900MHz 2.8" screen. Was advertised as a 4" touchscreen. I'm pretty sure it's a clone, a fake and a dud. It turns on ok but how do I

I have a new RF Demo Kit board that came with two connecting wires. One end is an SMA male connector and the other end is something that I have never seen before. It is supposed to connect to the test

Alan, I think the actual notch filter is ceramic piezoelectric. Probably more Q in a small package, and easier to keep on frequency. --John Gord

This arrangement would create the trap --- notch. Assigned a termination of 300 ohms loaded both sides.

The data sheet for the band reject, notch filter or TRAP is located at: https://datasheetspdf.com/pdf/1154516/Token/XT6.5MB/1 It appears to used in TV receivers and I suspect inside the unit is a

Andrea, I am not familiar with the band reject filter in circuit 5, but the filter in circuit 6 is probably a fairly standard 10.7 MHz ceramic bandpass filter once common in FM receivers. These

I meant "what the designer [...] wanted to do" I meant "I still don't know". And now it should be evident I'm oppressed by my own oversights and I'd love having the chance here to edit my messages

I'm sorry, I forgot to attach... :-( A.

On Mon, Oct 26, 2020 at 02:30 PM, alan victor wrote: > There is a fundamental idea that is easy to grasp but it has big implications > in achieving lossless > impedance matching. Although we can

\ Yes, this is very much the case. The other strategy is to design your system so you don't care. For instance, the NanoVNA itself is made on what I assume is FR4. But, because there's a calibration

Rogers Corp. provides a calculator called MWI (Microwave Impedance) which I find extremely useful. You have to sign up for a free account with them (which I have had anyway). Then you can download MWI

For accurate S11 measurements of that microstrip at 1 GHz. you need a good reference plane and termination load. You can't put an SMA connector at the end of the microstrip and then use a SMA male

FR4 or XXXP is significantly cheaper than Rogers, though. There are plenty of applications where you just don't care. A microwave motion detector at 10GHz has short traces, and doesn't care what the

The calibration load -- NanoVNA Wiki: /g/nanovna-users/wiki/home NanoVNA Files: /g/nanovna-users/files Erik, PD0EK

What did you use as a load for close to 50 +j0 at 1 GHz. ?? Roger

Far end was terminated with nominal load. This was 20cm coax! -- NanoVNA Wiki: /g/nanovna-users/wiki/home NanoVNA Files: /g/nanovna-users/files Erik, PD0EK

Yes -- NanoVNA Wiki: /g/nanovna-users/wiki/home NanoVNA Files: /g/nanovna-users/files Erik, PD0EK

Good point on FR4 Er vs frequency, I forget what reasonably affordable dielectrics do! Here are a couple of simulations of microstrip: Er vs freq from

Roger & the group, I stand corrected.The Z0 does change with freq.For coax, the change is small (<5%).For Ham purposes (HF), it is negligible.For VHF & UHF, if you use quality coax (Heliax), it is