On 28 Sep 2014 11:37, "Poul-Henning Kamp" <[email protected]> wrote: > There's a pretty excellent 10->200 MHz multiplier in your HP5370. > > Consider using it for an experiment to see if your idea even works...
I know longer have that - I sold it to someone on this list, then later regretted selling it! But I do have a signal generator to test the idea. I must admit I am not 100% confident I can make it work - at least not in a way I can get all 4 S parameters. I think it is relatively easy if you have access to several internal signals in the VNA, but not so easy if the VNA has a built in test set, and no access to the switch or directed access to the receivers. There are commercially available extenders that make a 30 GHz VNA work at 1 THz or more, but these require access to certain signals I don't have. I was for example thinking of using photo diodes to detect the position of the test set, as there's a couple of LEDs on the front panel which indicate whether the souce is routed to port 1 or 2. Another possibility is perhaps sensing the RF power, but that could be tricky as one doesn't know what direction it is flowing. One would with a very high directivity coupler, but I don't think that is practical. The source in the VNA can be set as low was -40 dBm, but a DUT could inject +20 dBm into the port. The damage threshold is +30 dBm. So I don't see an easy way of knowing which port is energised. Sticking light sensors near LEDs is not very elegant, but I can't think of a better way! _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
