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Cheap and easy portable 2-meter Yagi

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Feb 24, 2001
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#1
This Yagi is made from 1/2" copper and PVC pipe. It dismantles for transport and takes about a minute to assemble in the field.
It uses a beta match and gets a 1.5:1 VSWR at the band limits, with about 1.3:1 at 146 MHz.
The H/T belt clip is connected to the boom with a hose clamp.
I already had the copper pipe and connectors. The PVC pipe and fittings cost less than $10 with enough pipe left over to make more.
Originally, I planned to reinforce the boom with a 5/8" oak dowel, but it seems to be rigid enough without.
I took it for a hike today on a hilltop and got great results.
 

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Feb 24, 2001
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65,126
Location
Virginia
#4
N4GIX,
Awkward, yes, it is somewhat. I'm already thinking about mods. Two things come to mind:
1) Finding a longer TX line; and,
2) Adding a tee at the balance point on the boom to accommodate a short mast pipe, then attaching a metal spike at the bottom of the mast. That way, when I'm hill-topping, I can stick it in the ground and save my arm.
Thanks, all, and 73s.
 
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Messages
65,126
Location
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#5
Rev. 1

Here's the Yagi with a tee added to the boom and a 3-foot mast.
The drivers have been trimmed for better tuning and the match has been tweaked to get the VSWR down.
I'm still looking for some 50-Ohm cable to improve the TX line setup.
 

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Joined
Aug 9, 2012
Messages
4
Location
Saint-Jean-sur-Richelieu,PQ.Canada
#6
Diagram and Data for Cheap and easy portable 2-meter Yagi

Hi kiloechozero

Very interesting this small antenna, but not much info other than pictures.

Do you have a detailed plan with mesurement to build this antenna? Specially the improved one (last picture with 3' mast)

also Specification for the Beta Match

73

Daniel VA2DG
 
Joined
Feb 24, 2001
Messages
65,126
Location
Virginia
#10
KB5ZCS,
See K7MEM's calculator here ... Martin E. Meserve - K7MEM - VHF/UHF Yagi Antenna Quick Designer
I used the DL6WU spacing.
If you use a cross for the director fitting, then you can easily add an extension for the boom. At one point I added a second director, but noticed that the boom has to be reinforced as it becomes floppy. Also, the balance point for the mast has to be changed. A more rigid mast might also help if you are going beyond 3 elements.
Good luck and 73
 
Joined
Jun 30, 2006
Messages
7,285
Location
So Cal - Richardson, TX - Tewksbury, MA
#11
I don't think there is anything cheap or portable about a copper pipe Yagi. There are lots of plans for one made from old tape measure or nearly free new ones from Harbor Freight. The Yagi will be about the same size as the OPs but the elements will fold down so the antenna is only the size of the boom and it will be a lot lighter weight.
prcguy
 

SCPD

Member
Joined
Feb 24, 2001
Messages
65,126
Location
Virginia
#12
This Yagi is made from 1/2" copper and PVC pipe. It dismantles for transport and takes about a minute to assemble in the field.
It uses a beta match and gets a 1.5:1 VSWR at the band limits, with about 1.3:1 at 146 MHz.
The H/T belt clip is connected to the boom with a hose clamp.
I already had the copper pipe and connectors. The PVC pipe and fittings cost less than $10 with enough pipe left over to make more.
Originally, I planned to reinforce the boom with a 5/8" oak dowel, but it seems to be rigid enough without.
I took it for a hike today on a hilltop and got great results.
maybe awkward to hike with but it probably works great
 
Joined
Mar 4, 2004
Messages
524
Location
Crafton Pennsylvania
#13
Thinking back to when I was in the Army and came across a portable yagi utilizing telescopic whips. This was for a tactical low band DF unit someone brought into the C&E shop. Would like to make several, one for 6 and the other 2 meters.

Just gotta sit down and do the design work. Would be sharp getting one on 440.
 
Joined
Dec 6, 2008
Messages
52
Location
Bergen County,NJ
#14
I know nothing about antenna's, what frequency would this work with? I use my radio for only railfanning. Would something like this work if setup at a location where you plan to just sit for hours?
 
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