Hi David,
Is there any chance that you could convert the Word document to a PDF which would allow the likes of myself to read it.
I don't want to buy a later version of MS Office than the one I use now.
Keith ZL2TPQ
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------ Original Message ------
From: "David Eckhardt" <davearea51a@...>
To: "NANO VNA" <
[email protected]>
Sent: 14/01/2020 7:06:56 AM
Subject: Re: [nanovna-users] How to find the right ferrite toroid for a receiving antenna balun?
The attachments may be of some help. Generally, for HF, 43, 73 or 75
material is used.
Wind your transformer. Properly calibrate the VNA with SOL over the
frequency range of interest - no through is required as you need only a
one-port cal for the measurement. Connect one set of windings to the S11
port. Terminate the other set of windings with a 450-ohm non-inductive
resistor. Measure the side connected to the Port 0 (the S11 port). If
this is 'off scale' or hard to read, try a resistor value half that value.
The impedance transformation will be close to the 450-ohm termination read
with the lower value when 450-ohm terminates the transformer, but may be
easier to real. Things should end up on the right side of the Smith Chart
(the High-Z side).
Dave - W?LEV
On Mon, Jan 13, 2020 at 4:09 PM <ohansmit@...> wrote:
This one covers various core materials.
Regards
Ohan, ZS1SCI
--
*Dave - W?LEV*
*Just Let Darwin Work*
*Just Think*
