Fieldcraft Antenna's, Homemade.

[Sean the Nailer]

Hey there Guns, et al

One of the guys from the club here, who helped me out by programming my radio's, has a number of towers here in this province. He told me about building my own external antenna for my portables. Said that they'll pick up and send to practically anywhere within the Perimeter Highway. (that is the highway circling this city.

Just a simple SO-239 and 5 wires 19" long.

Connected to the radio via RG-58 or RG-59.

According the the guy at the local radio supply store (who didn't have any of the above parts, but had wire) I could go with a cable up to 100' long from the portable, and I wouldn't hardly know the difference. I was expecting him to say something completely different. ie exponential degradation with increased length. I was wrong.

Thoughts?

I haven't quite figured out how I'm going to attach it to the garage, considering that the holes will have the wires soldered into them. Is there an "extended" PL-259 or anything like that, that I can attach to the fascia? Or am I barking up the wrong tree?

@Gunfighter14e2 , @W54/XM-388 and any others who know what they're talking about.

And, a guy in the club said he's set a pair aside for me. Just gotta pick 'em up. Probably Friday morning.

 

[fxdwgkd]

Built a handful of roll up j-poles for guys using 300ohm antenna wire and rg59 cable. I used 25 or 50ft of wire depending on what they wanted. One guy just mounted it in his attic to get better range from his ht. I have one in my pack to string up a tree to get more range, and it does make a difference.
Could use a bulkhead fitting from here to get through the fascia. https://www.alliedelec.com/coaxial-rf-connectors/rf-adapters-in-series/

The bulkhead fitting will depend on the fittings on the cable or whatever fitting you decide to solder on the cable. Also another option.

Amphenol RF - 083-1R - Connector; RF; Coaxial; UHF; Panel Jack; Straight; 4-Hole Flange; UHF Series - Allied Electronics & Automation

083-1R from Amphenol RF at Allied Electronics & Automation

www.alliedelec.com

 

[W54/XM-388]

My house plan is just to have holes for the wires to go through with some conduit & then not have any more connectors than I need, just 1 connector put on at the antenna end and 1 on the radio end.

 

[Sean the Nailer]

That is exactly what I'm doing. In this case, the SO-239 bulkhead connector IS the antenna body. The wires will be soldered (TIG'ed???) directly onto it. I'm thinking of using 304 st st TIG filler rod for the 5-19" lengths. I won't know until I actually have one of these in hand. Otherwise, I don't know what would be best for the wires due to outdoor conditions.
-has to be strong/stiff enough to withstand wind and not get all bent.
-has be be "attachable" to the SO-239 via solder/braze/or fuse (weld)
-I'm guessing that it has to be "non-corrode-able" or non-tarnishable... or does that make a difference? Considering the copper J-tube antenna's out there, maybe that isn't a worthy consideration???? I dunno.

The gentleman that pointed me into this direction is extremely knowledgeable. Only issue is ability for me to connect with him is minimal, AND there's a bit of communication/translation difference.

Hence why I'm asking here too.

 

[Alpine 338]

If going with a bulk head connector, I would suggest wrapping the connection with weather proof tape. I forget what it's called, but basically it's rubber tape, that when stretched, it sticks to itself, no adhesive. To remove it, just cut it with a sharp knife or razor, and there's no adhesive residue left over to clean off. I also suggest putting a cap on the connector when not in use to prevent corrosion.

As far as coax, yes, you can go quite a bit on length, but just realize not all coax is the same. RG-58 has a lot of loss compared to RG-8 or RG-214. If going a long ways, spend the extra money on the better cable.

If your transmitting on the antenna, you'll want to use a coax that has an impedance of 50-ohms. Stay away from RG-59 or RG-6 as they have an impedance of 75-ohms.

 

[Alpine 338]

Coax-seal is one brand of tape.

Coax-Seal - The Original Connector Sealant

The Original Connector Sealant

coaxseal.com

It uses a mastic compound that can be pretty messy. Unless it's a permanent installation, I would stay away from it.
If you do use it, after application, wrap it with 3M Super 33 or 88 electrical tape.

This silicone based tape works well, but it can unravel if not applied correctly.

CW10B Silicone WeatherProofing Tape, Black, 10 feet, COAXWRAP

CW10B Silicone WeatherProofing Tape, Black, 10 feet, COAXWRAP Create a long lasting air and water tight seal with no sticky mess with CoaxWrap™ Silicone Tape Color: Black Length: 10 ft

www.rfparts.com

Again, I prefer the natural rubber coax sealing tape. I've purchased it from Tessco before, but can't seem to find it looking at their website.

 

[Alpine 338]

I've used this stuff before, but kind of thick for wrapping smaller coax connectors.

Scotch® Rubber Splicing Tape 23 | 3M United States

www.3m.com

 

[missed]

Scotch 130C is great for taping up splices. Much better than a vinyl based tape.

 

[Gunfighter14e2]

Did not see this until just now.
100' yea RX w/o issue, but TX, remember the feed line is also part of the antenna. So before you key up best check the SWR! Most radios will fold back (drop power) automatically when SWR is greater than 3/1 some won't, don't know about the fangs on that one.
Search ---> My feed line tunes my antenna<---
There are many ways to skin the connection cat depending your end game. RF connectors cover the whole spectrum just make sure your using the correct ohm for the feed line your using. Mixing a 50 ohm in with anything not 50 ohm can cause tuning issues that will make you scratch your head for a while. I know a guy that ran his self around in circles for over a year trying to tune an array he built. Took 2 of us 3 hrs to find it an 10 minutes to fix it. He was a local TV Broadcast Engineer an had intermixed some bulkhead fittings that were between two inter walls, oh yea that was fun to find.

 

[Sean the Nailer]

I still have to physically measure the intended distance between radio and antenna mount, but I expect it to be somewhere around 50'ish feet.

Going out today to get some connections and whatnot, so we'll see how things progress. Juggling a lot on our end here, so things aren't moving forward NEAR as much as I want them to be. I am moving forward though.

 

[Sean the Nailer]

Ok, much to my surprise, I'm looking at 70 feet ish, and that surprises me. I figured it was going to be around 50. To which the ground plane antenna would actually be 15' off the ground. Still ok for the Yaesu?

 

[Gunfighter14e2]

Should be but,.... borrow a antenna analyzer an check it prior to keying up. Someone in a local club will have one.

 

[Sean the Nailer]

Guns, regarding this "ground plane" antenna I'm wanting to build, I have 5 antenna wires. Each has the fancy 'ball' on one end. 4 are 20 1/2" whereas the 5th one is 18 3/4".

My question is simply out of "pedantic-ness" in the sense of "I was told to get 5 wires that were 19" long and then assemble..."

I don't know how precise this needs to be, and obviously I can cut the long ones to size, but that short one can't be 'uncut'. SO, do I need to get a longer one?

In one extreme, it won't matter a whit. In the other extreme, it makes the difference between working and not-working, and I don't know either way.

Hence why I gotta ask. Thanks.

 

[Gunfighter14e2]

Sounds like your building a 2 meter Discone do you have a drawing of what your making?

 

[Gunfighter14e2]

Does your drawing look like any of These ?

 

[Crang]

This improvised jungle antennae is my next experiment. He mostly moved from this blog over to the American Partisan but worth following-

The Jungle Antenna

The Jungle Antenna AKA 292 Antenna AKA Quarterwave Groundplane is a groundplane antenna made of just a few common parts. As the nickname implies it’s designed to work in rural, woodland areas…

brushbeater.wordpress.com

 

[Sean the Nailer]

The sketch he gave me, and the verbal description, comes out as "this one"

Though that picture seems to be 'arrow shafts' and whatnot. I was told to get 5 wires that were 19" long, and mount the bottom four at 45degrees 'down' with the fifth one being 'up'. The top one is to the 'center lead' of the PU-239 (or whatever it's called, I forget) and the base four are soldered to the body. I then isolate it on a mount, and go from there.

It wasn't till I got home that I found that the one antenna wire was 18 3/4". I specifically asked the sales-dude at the radio shop, and he went behind the wall to the tool area and 'measured it' and came back saying "yup, it's 19 inches all-right!".

So, seeing as I don't know from shine-o-la, does that quarter of an inch make a difference, or no? That shop is at the other end of the city, so it isn't a frivolous ride to get there. If you're going to say that it DOES make a difference, I'm going to want to skewer this guy for lying to me. And yeah, that would then be the second time I got lied to, by that shop.

 

[Gunfighter14e2]

The sketch he gave me, and the verbal description, comes out as "this one"

View attachment 7055588

Though that picture seems to be 'arrow shafts' and whatnot. I was told to get 5 wires that were 19" long, and mount the bottom four at 45degrees 'down' with the fifth one being 'up'. The top one is to the 'center lead' of the PU-239 (or whatever it's called, I forget) and the base four are soldered to the body. I then isolate it on a mount, and go from there.

It wasn't till I got home that I found that the one antenna wire was 18 3/4". I specifically asked the sales-dude at the radio shop, and he went behind the wall to the tool area and 'measured it' and came back saying "yup, it's 19 inches all-right!".

So, seeing as I don't know from shine-o-la, does that quarter of an inch make a difference, or no? That shop is at the other end of the city, so it isn't a frivolous ride to get there. If you're going to say that it DOES make a difference, I'm going to want to skewer this guy for lying to me. And yeah, that would then be the second time I got lied to, by that shop.

YES, that 0.25 will make a difference on 2 meters. The last J pole I tuned for 2 meters was done with a 12" file to get it perfect. Yours does not have to be that perfect but 1/4" is going to make a difference.
Just get some solid copper house wire an make your own antenna, or go to a junk yard an get some old car antennas, plus those will have the corona balls already in place. The little balls at the ends are corona balls, do you need them? For what your doing no. If someone could get close to the antenna, an touch it then yes you need them. If you want them on you can make them from larger copper wire an solder them on, but remember to cut the wire from the ball end, not the solder joint.