Highly recommend the LeoNTP. If you are in the US, there is still one in stock here: https://v3.airspy.us/product/upu-leontp/ Denny > On Nov 21, 2021, at 18:52, W7SLS <w7sls.scott at gmail.com> wrote: > > Another option is the Leo Bodnar NTP device, though it appears to be out of stock at the moment