The Mighty Doublet Antenna

[@JDHood]

Tractor Supply has electric fence insulators that are a uv resistant plastic tube (about 5"). Makes a good ladder line spreader. Drill 1/2" from each end, thread wire, shoot hot-glue in the end of the tube to fix it in place on the wire.

[@CoffeeandHamRadios]

Nice tip!

[@ozone385]

Watched on replay, great information. the Ladies need a CaHR Tumbler and then you can monitor thier intake. LOL

[@CoffeeandHamRadios]

Lol

[@chazcheadle]

I have used a ~100ft 300Ohm ladder line doublet with ~72 ft radiating elements at 30ft and been able to tune it with the G90. The XPA125b and x6100 could only one or two bands.

[@owlcricker-k7ulm]

Tune it for the height you deploy it. That gives the best idea of which balun is best for you. Great antenna, it is the same set up needs as a dipole. I love it for portable ops where speed isn't an issue

[@eliezercohen2205]

If you supply the wire and 3d printed spacers the customer can make their own ladder line.

[@CoffeeandHamRadios]

Fair point

[@JDHood]

Bottom Line Up Front: Balanced feedline fed dipoles (a doublet) can work multiple bands without suffering power losses from high SWR like coax fed dipoles, all else being equal. Long winded version: Why a doublet? It's best use-case is when you can only fit one wire antenna and it has to work multiple bands. Having to work multi-bands means the antenna is mostly going to be non-resonant and SWR will be anywhere from "ok" to "OMG!" high. More often than not, it will be higher than a built in tuner can handle. With unbalanced coax, high SWR means you are losing power heating up the dielectric, the balun, and whatever else is resisting the flow prior to the feedpoint. With balanced feedline, the typical dielectric is "air" and it does not lose/sap power on the way to the feedpoint (well - it still does have **some** loss, but it's negligible compared to coax). And as long as the radiator is at least a half wave length (or longer) for the freq of interest, it will happily radiate whatever power you can get to the feedpoint regardless of resonance. The trick is getting that power to the feedpoint as intact as possible. Coax can be super lossy in this use case (multi-band, single wire antenna), where balanced feedline isn't, relatively speaking.

[@CoffeeandHamRadios]

I’d tend to agree with all of that, thank you for the post 👍

[@Siskiyous6]

Good show

[@CoffeeandHamRadios]

Thanks LC 👍

[@owlcricker-k7ulm]

NorCal doublet is great. The speaker wire antenna is the same thing. NoCal is super light and portable

[@CoffeeandHamRadios]

Yeah, one of these days I’ll build one 👍

[@WU3Shamradio]

Great livestream, im getting ready to build a doublet, I'm looking to use DX50, with the doublet Center from Callum at DX Commander!

[@CoffeeandHamRadios]

Good luck with the build!

[@jamesknotts1546]

I got my day started off with pota

[@CoffeeandHamRadios]

Nice 👍

[@cornbread-KO5RN]

👋

[@N2EWSRadio]

Unboxing videos are boring to me. I know some people like them, but I fast forward to when people talk about or use the radio.

[@MikeN2MAK]

#TeamReplay