CB Fire Stik Dipole Question

[Marconi]

Sorry for the triple post but I have been aiming to build the exact same for fun and experimenting.

Highway Man, your idea sounds like a great project. Not sure if this particular comparison idea has been done already on the forum, but I encourage you to test your ideas and report back.

Maybe you could give us some ideas for how you plan to proceed in the mean time.

 

[Eldorado828]

I'm curious now, how do these dipole mounts behave towards the mast that they're mounted to?
Wouldn't you need to insulate it from the mast if for example it's a metallic pole mast?

 

[Highway Man]

I was thinking about a tree but not sure what the OP was thinking.

I found a two antenna trucker mirror mount that looks promising but Francis had what looked to be a better solution The fleabay trucker mount has the spacing further apart, maybe 6 inches. Not sure if that would negatively affect things.
Look at Mower Junkie's YouTube channel at the 102 SS whip dipole he recently made and put up on his house He says it does very well and the DX gates doesn't lie

 

[GA1dad]

I was thinking about a tree but not sure what the OP was thinking.

I'm still in the early thinkin' stage. I have plenty of trees to work with, two chimneys and a fairly long light duty fiber mast.

Currently I'm working to get a wire inverted vee up for 10 meters.

 

[2NC995]

I never found a noticeable difference from 5' to 4' when mounted TDC of the roof of a well bonded pickup and the 4' and 5' Firestik ll are exactly the same with the 5 having 5 or 6 extra long twist ( windings) at the base. There isn't a complete foot difference in length that I can tell without accurately measuring.

I don’t doubt that at all. At some point when you shorten an antenna the performance starts to drop off...and I’ve made my limit 5’. It’s totally arbitrary

Usually when I hear people speak of S units of difference, I shrug it off. I have no two mobile CB antennas where I’m able to see much more than a needle width on the receiving end. Ive seen biggest differences pop up when you get all the way at the end of the range on a quiet night and the S meter isn’t even moving anymore. Then suddenly the weakest antenna (almost always the shortest) drops out.

In terms of just S units, last comparison I did was a whip, a pres texas, a 10k, and a Wilson 5k. They were all within a needle width on the RX end, but at max distance, they fell out of the receive in order of length.

 

[Highway Man]

What I was saying is I've never went from a good signal with someone on a 5 foot Silverload then changed to a 3 or 4 footer and them drop out

 

[2NC995]

What I was saying is I've never went from a good signal with someone on a 5 foot Silverload then changed to a 3 or 4 footer and them drop out

I think I agree with you more than not and maybe we’re just phrasing things a bit differently.

I tend to think there is a difference in the performance of those antennas, your 3,4 and 5’er, but it’s much more subtle than one might think and your observations make 100% sense to me.

If we narrowed it down to just two, a 4’ and 5’, I’d actually be shocked if the receiving station could detect any difference under most situations.

Get to the far end of range, on an exceptionally quiet night, and I think any difference would be *barely* detectable.

 

[Highway Man]

I have to agree with you.

 

[2NC995]

I have to agree with you.

It’s also why I asked M0GVZ what he meant by 25% efficiency of a dipole.

You’re obviously not going to have a conventional dipole give an S8, and the planned antenna give an S2...I think we all agree on that.

But I also don’t know what the 25% is in relation to?

I have a wide inverted V in my attic...and I have no problem staying in touch with my son in his mobile up to 20 miles (both of us running 12watts). My antenna is crammed in among house wiring and HVAC ducts...

 

[Rick330man]

I have two of those MFJ mounts. They are simple, work well and make it really easy to do the kind of experimenting you're contemplating.

I've posted on here about the dipole rig I take out on my boat. It is a 102" piece of 3/4" aluminum stock, a mobile rail mount and a 102" stainless steel whip on the end. It can't get any simpler. SWR across the CB band is just a hair over 1.5:1. I can set it up in 5 minutes. A couple of weeks ago, from here in the lower Florida Keys using it with my barefoot Cherokee AH100 walkie talkie I made contact with the big island in Hawaii: 4800 miles. Locally, this set up works as well as did my considerably pricier Shakespeare 176-1, half wave marine CB antenna.

Experiment. Have fun. Let us know your results.

 

[Highway Man]

I just had the idea of bolting 2 mirror mounts together and 2 firestik k4 studs just omitting the insulation washer on counterpoise side.

The extra 4 little holes you could use to sew to a 2x4 or like for a mast in a tree

 

[hotrod]

I don’t doubt that at all. At some point when you shorten an antenna the performance starts to drop off...and I’ve made my limit 5’. It’s totally arbitrary

Usually when I hear people speak of S units of difference, I shrug it off. I have no two mobile CB antennas where I’m able to see much more than a needle width on the receiving end. Ive seen biggest differences pop up when you get all the way at the end of the range on a quiet night and the S meter isn’t even moving anymore. Then suddenly the weakest antenna (almost always the shortest) drops out.

In terms of just S units, last comparison I did was a whip, a pres texas, a 10k, and a Wilson 5k. They were all within a needle width on the RX end, but at max distance, they fell out of the receive in order of length.

this test sounds reasonacble..for overlenth i would president texas won

 

[unit_399]

When we moved to Colombia in '07, I wanted to get my station on the air ASAP. I only had an A99, and a few mobile antennas. I put up the A99, but the skip contacts were pretty sketchy. So I said WTH, and made a dipole out of 2 PAL firesticks: a 4 footer and a 5 footer (I didn't have 2 of the same length). Put it atop a 33' pvc pipe bolted to a 36' piece of guada (so I could rotate it) and proceded to talk all over the US and the Caribbean islands.
So... for anyone who is wondering, the answer is YES it will work.
Some pics.



I put a mobile "gumdrop" mount on a piece of aluminum diamond plate. Put the 5' stick in it. Drilled a 3/8" hole in the plate and bolted the 4' stick to it. Rolled up several turns of coax as a CMC choke. Necessity is the mother of invention.

- 399

 

[Highway Man]

When we moved to Colombia in '07, I wanted to get my station on the air ASAP. I only had an A99, and a few mobile antennas. I put up the A99, but the skip contacts were pretty sketchy. So I said WTH, and made a dipole out of 2 PAL firesticks: a 4 footer and a 5 footer (I didn;t have 2 of the same length). Put it atop a 33' pvc pipe bolted to a 36' piece of guada (so I could rotate it) and proceded to talk all over the US and the Caribbean islands.
So... for anyone who is wondering, the answer is YES it will work.
Some pics.
View attachment 36627
View attachment 36628

I put a mobile "gumdrop" mount on a piece of aluminum diamond plate. Put the 5' stick in it. Drilled a 3/8" hole in the plate and bolted the 4' stick to it. Rolled up several turns of coax as a CMC choke. Necessity is the mother of invention.

- 399

That's good stuff especially for the nasayers.
Thanks for sharing

 

[Marconi]

I remember years ago, I talk to JJ (399) a lot...or so it seems.