Here is what I use for my flag antenna. Works great.
Click on KD9SV products then click on his KD9SV pennant transformer and
resistor. 9/1 xfmr and resistor ready to go for a flag or pennant.
> I have a flag antenna which has worked well for several years. I used a
> Minicircuits T16-6 transformer to couple the ~800 ohm termination resistance
> of the antenna to 50 ohm line. Recently I decided to do some upgrades, so I
> followed the recommendations of many (here and elsewhere) and made a matching
> transformer using an FT-140-43 core and 34:8 turns, secondary and primary on
> opposite sides of the core. I didn't have any #28 wire so I used #24. I
> tested this with a miniVNA, terminating the antenna side with an 800 ohm
> noninductive resistor. The impedance does not look right at all; there is a
> lot of inductive reactance and the resistive part starts at 125 ohms and
> climbs steeply from 1.7 MHz. No on-the-air results yet.
> I'm wondering if this is right or not - measurements indicate the DIY
> transformer is much worse than the T16-6 in terms of presenting a good match.
> This would not be the first case of theory saying it won't work but practice
> says it will - just looking for a reality check here. Seems to me like the
> core material is all wrong...
> -Tony, K1KP
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