beginner wrote:

It is FT82-75 and the resistance is only 5 KOhm, so the mix is accurate.

I will have to make use of them in wideband tranmission transformers.
Can you folks suggest a frequency range?

I can get ferrite #61 or #63, but iron core only comes in mix #2 or #6
locally.

Mix #2 should be OK for your crystal set.

With a transmission line transformer you should be able to go up to 100
MHz or more, the core is only important at the lower part of the
frequency range.

Leon
--
Leon Heller, G1HSM
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