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View Full Version : 5/8 wave, 2M Homebrew Antenna


Groucho
02-27-2008, 10:25 AM
I am currently making the parts to allow those interested to get together and build this antenna to use on your vehicle. It is identical to the one seen on my FZJ80 and Bruce's HDJ80(at the last HAM class).

It is fairly simple to do, and it will make a nice addition to your HAM setup. The only thing you would be required to purchase is a length of coax with a PL-259 on one end. That may run around $7.

I am looking for a show of interest so I know how many I need to machine parts for. I am not looking to charge people for this at all, just to encourage the "tinkering" that HAM radio does.

Please post up if you would be interested in getting to gether some weekend day for an hour or two and build yourself an antenna.

73'

Mendocino
02-27-2008, 10:32 AM
Count me in!

Romer
02-27-2008, 10:49 AM
I might, you have a picture?

Hants
02-27-2008, 11:47 AM
Details, please, as I wasn't at the meeting. :)

Mounted to _______? Pics would be great!

For those of use with dual-band radios, would we need to also build a 70CM antenna and source a duplexer?

Generally, yes, I'm interested.

treerootCO
02-27-2008, 11:49 AM
I am at your mercy as to what equipment I need and what you feel is the best setup. Should you feel this is what I need after I get certified, then count me in. I promise not to hook it up to anything until I pass my test.

subzali
02-27-2008, 11:53 AM
Mike you can always hook it up beforehand and listen in - just no transmitting!

Nathaniel, I'm interested, count me in.

RicardoJM
02-27-2008, 12:27 PM
Nathaniel, the FJ40 needs an antenna. Count me in.

subzali
02-27-2008, 12:47 PM
Speaking of that, sign me up for two :D

Groucho
02-27-2008, 01:32 PM
I will at some point soon post a picture of what this looks like in person. Until then, here is some verbal info...

For those of you who were not at the first HAM wives class (where I handed out copies of the QST article from June 1979) this is a simple 2M, 5/8λ Vertical, single band antenna that in 1978 was supposed to cost all of $2-$3 (without the machined cone--see further down).
It is composed of a piece of 3/4" plexiglass 3 1/2" long, to which a coil of 10GA copper wire is wraped around. Out of the top of the plexiglass is a whip made of 1/8" stainless rod, welded to a 1/4 x 20 x 3/4" stainless bolt with a machined cone welded to the top for support (so the whip doesn't tear at the top of the bolt).

While many arguments have been made about the difference between 1/2λ and 5/8λ, this has been very effective all last year getting into repeaters as well as on trail runs (Ghost Town, Ouray).

This is simply a project that is supposed to accompany the HAM class info to make the learning about antennas enjoyable and practical. The parts to assemble would normally cost about $10-$15 per antenna (not including the coax), but it is being offered for FREE (all but the coax).

If you decide to come and build one, but never use it, all I will ask is that you either donate it back to me to give away to someone in the club who might use it, or give it to someone in the club who might use it yourself. :thumb:

The date will be TBD, but hopefully before March 17th.

corsair23
02-27-2008, 03:26 PM
QSL

I'd like to be in for at least one, two if they aren't easily moveable between rigs :thumb:

Tramontana
02-27-2008, 06:18 PM
...but it will depend upon scheduling.

My Kokopelli Ride is March 14-17 so I can't that weekend. Any other days or evenings other then Wednesday nights work for me.

Cheers!

Jethro
02-27-2008, 08:02 PM
Free?

Yeah shucks, put me down for one of those!

nuclearlemon
02-28-2008, 07:14 PM
i'd like one.
thanks nathaniel

Convert
02-28-2008, 08:48 PM
Nathaniel
I am interested Thanks:thumb:

Romer
02-28-2008, 10:14 PM
still waiting for the pics :ranger:

Groucho
02-29-2008, 07:04 AM
Here is a picture. I didn't use shrinkwrap tubing on mine, but Bruce did. The entire coil gets shrinkwrap tubing around it. So mine has a year of corrosion on it.

You can see the plexiglass rod (black part that the copper wire gets wraped around), the copper wire (that is now green). The machined cone on the top and the whip.

I am going to post a .pdf with the article soon.

Groucho
02-29-2008, 07:58 AM
For everyones enjoyment.

DaveInDenver
02-29-2008, 08:17 AM
You know what would be sweet is if an NMO mount could also be rigged up. Also that would only be needed for knuckleheads that have drilled holes in the sheet metal of their junk...

Uncle Ben
02-29-2008, 09:15 AM
Question;
Would this be a good antenna to mount on the garage roof so for the HT in the "Shack?" :rolleyes: :cool:

DaveInDenver
02-29-2008, 09:19 AM
Would this be a good antenna to mount on the garage roof so for the HT in the "Shack?"
This is what I was thinking of building it for, as a base antenna. The only difference between a mobile antenna and a base antenna is how you configure the ground half of the antenna. On your truck you have the sheet metal and on a house you usually have to add ground radials under the whip.

Nathaniel, add +1 for me, please.

Uncle Ben
02-29-2008, 09:27 AM
So this is just the antenna and not the ground plane you have it on?

Groucho
02-29-2008, 09:52 AM
You can have mine. I am 99% done on my roofrack, and I will be using that as my groundplane. But for you, sir, I will gladly donate my old piece of sheetmetal groundplane to you. You putting it on the roof of your house?

Uncle Ben
02-29-2008, 10:05 AM
You can have mine. I am 99% done on my roofrack, and I will be using that as my groundplane. But for you, sir, I will gladly donate my old piece of sheetmetal groundplane to you. You putting it on the roof of your house?

Garage actually....so my super bad butt HT shack can get out and touch a nearby repeater! :lmao::lmao: :hill:

Groucho
03-20-2008, 02:03 PM
I have all of the pieces parts to assemble the homebrew antenna.

I am looking to have the build party be on the 6th of april. That is a sunday.

Who could make it then?

It would only take a couple-3 hours. Maybe from noon to 3pm? Location TBA.

Post up.

subzali
03-20-2008, 02:08 PM
I'll be there. Thanks Nathaniel! :thumb:

nuclearlemon
03-20-2008, 02:12 PM
cool, i'll mark it down

JohnInDenver
03-20-2008, 06:21 PM
Ditto!

John
KDODCU

Romer
03-20-2008, 06:29 PM
I might be. It's Rachel's birthday so it depends on whats going on

Convert
03-20-2008, 07:18 PM
I'm in thanks Nathaniel:thumb:

Hants
03-20-2008, 08:28 PM
I will probably be out of town again. :(

If not, I'll work on a hall pass. :)

RicardoJM
03-20-2008, 09:30 PM
April 6th would be a great day. Count me in.

corsair23
03-20-2008, 11:26 PM
I plan to attend if at all possible...

Jethro
03-21-2008, 10:33 AM
April 6 is good. Looks like I'll be there.

Chris
03-21-2008, 04:36 PM
Looks like I need this too, thanks!

Shorty
03-22-2008, 04:42 AM
I'm interested. Count me in.

Tramontana
03-30-2008, 05:10 PM
April 6th, noon to three with location TBD is the last "edit" that I see in this thread.

I'm still game. Anything that I can bring along?

Cheers!

Groucho
03-31-2008, 09:44 PM
Still trying to see if there is someplace else besides my house is a viable option.

Subzali
Nuclearlemon
JohnInDenver
Romer (Maybe)
Convert
Hants (Maybe)
RicardoJM
Corsir23 (Maybe)
Jethro
RedCruiser
Shorty
Tramontana

9 with 3 maybes.

It is supposed to be nice this weekend, so my garage might work for all this, but if someone wants to volunteer some space that might be nicer I'm all for it.

Nathaniel.

JohnInDenver
04-01-2008, 09:12 PM
Our 2 car Garage is available.

We are very near Monaco and Montview (aka 20th). Easy to get to from I70 and Quebec or from the Museum of Nature and Science (Colorado blvd and Montview). Enough parking for 2 in the garage and 2 or three 4x4 in the alley. The alley garage also opens up to the back yard. Lots of street parking. Two picnic tables and plenty of electrical outlets on the covered back porch. Also a small workshop next to the porch.
John
KDODCU

corsair23
04-02-2008, 12:06 AM
I could check into getting one of the rooms at one of the Rec centers down in the Ranch...Would mean quite a drive for those up North but should be PLENTY of space to work.

Let me know and I'll look into it. Normally you have to "rent" the rooms but if they don't have anything planned maybe they'll just let us use one of 'em.

Groucho
04-03-2008, 01:21 PM
After speaking with JohninDenver last night at the meeting, we will be having this assembly party at his house.

I think it willnot be more than 3 hours of time. I will ask John to PM me his address so that I may get that info to everyone who signed up.

Remember, bring a length of coax, probably no more that 10-15 feet long, with a PL-259 connector on one end. Soldering irons and solder would be helpful, too, if folks own them and can bring them.

I will have everything else we need.

See you Sunday!

corsair23
04-04-2008, 05:52 PM
Just to be clear....

Noon-3pm this Sunday the 6th at John's place then?

And we need to bring the coax with connector...Not being greedy but those of us that stated we could use two of these would we need two lengths of coax or is the thought that these are mobile enough to be moved from vehicle to vehicle (say mounted to an NMO mount on the hood or rear hatch)? My thought is that for now I am going to connect a HT (probably a VX-7R) up to these to use in my vehicles until I can afford to add a more "permanent" mobile rig as well :thumb:

JohnInDenver
04-05-2008, 09:11 PM
High noon Sunday 4-6-08.

I will be on 145.145 beginning 11:30 tomorrow till about 12:30 for directions if needed. or 3 3561279

JohnInDenver
KDODCU

Groucho
04-05-2008, 10:05 PM
This antenna will require a piece of coax to be soldered to the coil. It can only be removed by de-soldering it.

nuclearlemon
04-06-2008, 11:08 AM
i probably won't make it...still haven't gotten rear main seal done:(

subzali
04-06-2008, 11:42 AM
I think I got food poisoning - really sick last night and this morning so far, sorry Nathaniel :(

Romer
04-06-2008, 10:06 PM
I would have liked to have come so I could have one of these for my HT. Too many projects at Home getting ready for CM