In the mid-January, my old 80m dipole broke due to icing and heavy snow. It had a direct connection with a coax for too many years .... and I decided to be with a Choke when the Weater improve.I started tests with several noname ferrite toroids and nanoVNA-H v.3.3. After some measurements (according to Fair Rite ) the toroides turned out to be MgZn, 40x25x11mm with Initial ?i 2000 or a bit more.
Stacked two with 14 turns 1.12 mm enameled wire in thermo shrink tubing (max diameter 2mm - the toroids are small). Normal winding .... tested and Reisert style... the same result.To avoad fixture capacitance I connected the Choke
direct to calibrated plane of nanoVNA CH0 - CH1.
Used nanoVNA alone, after with NanoVNA Saver, and OneofEleven application.
Full House with Data ...I've made a try to burn the choke with my PA and 250W
noninductive dummy load (with some pauses).KEY Down on CW and 175 volts p/p on Tektronix osci.
That is 612 watts on the peaks....The core and windings were cold as before the test ...I know the real test is up on the feedpoint of the antenna....
Seems the Choke can be used on 3.5Mhz- never have had 1.8 Mhz.Only 3.5-432Mhz.
The screenshots are attached.
Will be good some Expert to say something about this Choke....till I waiting for FT240-31 toroids.
Best Regards !
