On Sat, May 17, 2025 at 03:14 PM, Ed Marciniak wrote:
It would be reasonable to try 61 mix NiZn ferrite with a 300C curie temperature, and mu of 125
Thanks. I tried lots of ferrite types on a VNA and quite a few were OK to use but I chose one that gave at least 70R ESR across 50 MHz to several GHz that was fairly stable on a VNA when heated. However, I would much rather find out what HP used and fit this instead. Maybe someone here may know what ferrite was used. I think the ESR at 50 MHz has to be at least 50 ohms as this is 'big' compared to the 2.7R of R1.
--
Regards
Jeremy
