Re: The T-Check confusion
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Hi Erik
Fantastic ... I did not know you was maintaining TAPR VNA (or I had forgotten it) Looking forward to follow your project. My transfer switch is also Sivers Lab but only PM7551 ? with a small control PCB with 5V to 28DC converter. It went bust recently so now supplied by good old fashion AC/DC converter. I did measure some WiFi channel filter with the VNWA successfully using a filter for the entire WiFi band to clean up the TX signal. That worked great. One og these days I will try it with the NanoVNA Kind regards Kurt -----Oprindelig meddelelse----- Fra: [email protected] <[email protected]> P? vegne af erik@... Sendt: 9. december 2019 14:30 Til: [email protected] Emne: Re: [nanovna-users] The T-Check confusion Hi Kurt. Thanks. This is the switch I bought: SIVERS LAB PHILIPS COAXIAL SWITCH 28V DC-18Ghz PM7553 Isolation below 1GHz is better than 80dB so I guess below 300MHz good enough. As I am currently the maintainer for the TAPR-VNA software so I can add whatever I want :-) Using the scikit-rf implementation as example I should be able to add (limited) 10/12 term calibration functionally to the TAPR-VNA SW, including controlling the transfer relay. Lately I have been trying to optimize and tune various filters such as a 2GHz cavity filter and as I have to tune 5 resonators it would be nice if I did not need to reverse the DUT all the time as for best tuning you need to see S11,S21,S22 and S12 together. So it is more a matter of being kind to SMA cables and connectors and making tuning faster and easier. For my home build VNA's I can also buy/build a second bridge, add a 4th receiver and put the transfer switch between the LO and the bridges. This will give me a fairly symmetrical setup allowing measurement of the errors in the bridge impedance. Disadvantage is the transfer switch is locked inside one VNA So many options to choose from, sounds like a hobby -- NanoVNA Wiki: </g/nanovna-users/wiki/home> /g/nanovna-users/wiki/home NanoVNA Files: </g/nanovna-users/files> /g/nanovna-users/files Erik, PD0EK |
Kurt Poulsen