My still all time favourite TRX's from back in the Day. IC-720 (A), 745 and 751A. I am very happy with my home made EFHW 49:1 antennas. I got a short version with almost 40ft. lenght + extension coil with 34µH. And a long version with 67ft. lenght. They working fine with me outdoors in the Fields. 73's de Your Friend Uncle Guenter

Thanks for sharing

Nicely done. Very informative. Using the punch is a nice touch but not everybody has one on their shelf. I do but I don't use it for holes in plastic. I just a Uni bit or as some people call them, a step bit. They make nice clean holes. I've also use a spade type bit but the hole is not as clean. Like you, I always use SS hardware. Barry, KU3X

Very nice! Where did you get the hole punch?

Greetings could you tell me what gain have the EFHW antenna. Excellent your video

Did you need any vent holes in the box to dissipate some heat?

if you used 2.4 k resistance for 49: 1. What resistance could I use for 64: 1?

I didn't see any mention of RF ground wires or a counterpoise - did you use one?

I am surprised nobody mentioned safety issue of the proximity to power lines. Noise is not the only problem Definitely not something I would do.

What's the purpose of using two cores taped together?

I have to wonder about the location of the loading coil. I recently constructed an EFHW @ roughly 66'. Once tuned, I added a 110mh loading coil and about 8' more wire to get 80M. It even tunes as a quarter wave on 160, but I won't win any contests with it. As I understand it, the length of the wire after the loading coil will be far less than the remainder of your 160M half-wave. I'd be inclined to remove it from the 136' point and add it toward the far end. Maybe before the 9.5' section. Frankly, you should not need a loading coil, as you appear to have 245' of wire. Something's not right. 243 would be resonant at 1.8 mhz. Keep experimenting. Maybe a 64:1 transformer would be better. Thanks for sharing your experience.

Core mix is your issue on 160m. I'm picking you used 43.

strange setup. to reach a good swr on 160, you should place the coil in the radiator at about the resonance length for 80m as a trap, so the part after the coil will only be for 160m ans extended by the coil itself. look at the examplex of a shorted multiband endfed 80-10 or 40-10 73 HB0HJK

What about a EFLW using 1 Mile long wire antenna.

You should not use ANY tape on your cores. Per K1RF, this degrade primary inductance and performance.

Why did you use so much glass tape?? And then wrap the entire transformer with the tape?? Using tape will only trap moisture.... Also, why did you not use a drill to twist the wires? ...a drill works much better than doing it by hand. The case should not be "extra tight"....most people recommend ADDING additional holes to prevent accumulation of moisture. You should probably use a crimp tool for the terminals to make a reliable connection...not a vice grip pliers.

I think this core prep is a total waste of time. Use teflon wire instead. Covering the core doesn't allow the core to quickly cool off if it gets warm. I have been using teflon wire for decades and it works very well. And the core can be dismantled easily when desired.

Do yourself a favor and remove that tape ! It only serves to hold in heat that can and will cause your swr to rise ! The 49:1 does heat up and needs air circulation to keep it cool!

Swr very bad.