75 Ohm Coax with Ziggy

[@WECB640]

Well done Ziggy! 73 OM

[@75ohmHAM]

Achievement Unlocked! 75's Hollywood!!!

[@Hank_W6IR]

Great job 'splaining things Ziggy.

[@75ohmHAM]

Learnt from the Master😅

[@Swamp-Fox]

Now I'm gonna have to get some 75 Ohm coax!

[@75ohmHAM]

Do it, it's cheap!!!

[@mattxoverbey]

I’ve been waiting for a video series from you on this since I first heard you mention using it on one of the cahrs live stream. Admittedly I’ve been skeptical of using 75ohm coax but the numbers you’re showing, my skepticism has slowly started to go away. Can’t wait to see more of this. Great video Ziggy.

[@75ohmHAM]

I'm glad I could 'splain it to ya, thanks for being there for me

[@mikearmstrong9899]

Be going through this a few times before it sinks in. Seems money can be saved if you burn brain matter! You deserve way more subs.

[@75ohmHAM]

dude, seriously the nicest thing from the comments! Bravo 🎉

[@robertmeyer4744]

Great work ZIGGY ! I have been using different coax for many years now. I use BNC on RG6U and RG 11/U 75 ohm coax. Goes right in CaHR antennas' ! I have had good luck with the 9:1 random wire antenna using 75 OHM feed line. I find tuning easier. DX Engineering does sell RG 11U 75 OHM coax and that takes full legal power ! In fact RG 59/U 75 ohm is used on CB for that co phasing harness used to use 2 antennas on a truck . This has been common since the early 70's on CB for truckers . Go threw the old ARRL books you will see how common 75 OHM feed line was. I use M & P RG 11/U all copper 75 OHM coax . The famous DX Commander has a spool of it for the 4 square antenna he working on. Watch his youtube ! The best part of HAM radio I like is the ability to experiment and try different things. 73 and ham harder with that 75 OHM COAX !!

[@75ohmHAM]

@@robertmeyer4744 thanks Robert, I can always count on you

[@MikeN2MAK]

This is super helpful! I've been thinking about experimenting with some 75 Ohm coax.

[@75ohmHAM]

I'm here for ya, until bitter Zero X Homie!!!

[@TheSmokinApe]

Nice work Ziggy!

[@75ohmHAM]

This is your fault hihi

[@temporarilyoffline]

This is legendary

[@75ohmHAM]

@@temporarilyoffline thanks buddy

[@drall912]

i'm glad its all Ape's fault. Lol. This is going to be great.

[@75ohmHAM]

He is a great friend

[@Tom-n5tti]

Hey - discovered your channel after TO's livestream. I used RG6 coax for years when I got back into the hobby in 2012. I didn't worry about coax length as much as I worried about preventing water ingress. (the shield is aluminum) My old FT-101's finals seemed to have a better dip using 75 ohm coax, and my 2 meter packet repeater didn't seem to mind at all.

[@75ohmHAM]

@@Tom-n5tti I use the standard F compression connectors, so I hope ingress isn't so much an issue with them. The cool part for me, is the amount of variations of this stuff. My current spool has a steel woven jacket, spec sheet calls it trunk line. I didn't science the length at first either, now I have super powers :) ft101 with the E Band hihi, nice to meet you Tom send me an email ziggybuilds@gmail

[@Tom-n5tti]

@@75ohmHAM Steel woven jacket - NICE - I found a little petroleum jelly and electrical tape prevented ingress.

[@ka2aubsworld]

I kept asking myself why am I not using RG-6.

[@75ohmHAM]

I just scored another 500ft roll, $18 on market, mega SK loop with matching stub and tuned feeder, all out super cheap rg6

[@dorvinion]

So, what do you do with any excess from the 120ish feet? Coil it up? Wife doesn't like the fan dipole in the attic (EMF, even though I only run 25w max) so to make her happier thinking about building a home brew dx-commander like vertical in the (smallish - 60ft max distance) back yard. I got a whole bunch of RG-6 to use but my yard is nowhere near 120ft (though I guess the 120ft is based on an inverted v dipole and I'd have to adjust length to correspond to the measured impedance of the vertical) Cable techs quite literally threw at least 150ft of RG-6 in my trash can after they buried a replacement drop. Wasn't a ham at the time but knew there was no way I was going to let that end up in a landfill without someday finding a use for it.

[@75ohmHAM]

The excess? DM me on the Toads Discord. I got all the charts and slides for ya homie!

[@75ohmHAM]

So the coax doesn't care about the antenna you're using, you tune the length of the coax, 60' bounces off 10, 15, 20, 40 etc, 2x that bounces also between those bounces, get a copy of SimNEC and I can walk ya through how I do it

[@75ohmHAM]

Also if you tell me the band I can get you a rough idea for workable lengths you can use

[@dorvinion]

@@75ohmHAM The reason I was thinking the type of antenna might make a difference in length of coax you need is at 10:00 you had shown a slide with a practical example with a dipole that had impedance of 100 ohm at the desired frequency So that is why I was thinking that I'd have to build the antenna, measure impedance at the antenna for each of the bands I'm targeting (I'd think they they should all be close) and then with the help of the software, tune the length of the 75ohm cable so that it makes the closest match I do think I'm missing something that would be answered by giving the software a try I'll have to work on getting discord (verification always stops me because it won't verify with voip numbers) Not to say you're explanation isn't clear its more I learn best by seeing it work myself. You provided the spark

[@75ohmHAM]

I don't tune my coax to the antenna, simply tune the 'stub for highest SWR on the band(s) of interest with a 50Ω dummy load, for a dipole or fan dipole, it'll flip around when you connect it to the dipole, 75Ω match at the antenna 50Ω match presented to your radio. For others, like an end fed Half wave, you can find those two basic lengths to serve you well, 60 & 120 but all coax is different so you must find your spec sheet VF (always available) for the 75Ω you own. ziggybuilds@gmail and I'll help ya