This is my 80M "field expedient" antenna.
I primarily use this as a NVIS antenna with my FT-817 QRP rig.
- 16 Gauge Speaker Wire
- Crimp style BNC connector
- Radio Shack right angle "solderless" connector
- F-F-F BNC T from Radio Shack
- 2 16 Gauge Ring Terminals
- Cut the zip cord a bit long (as usual) ~68 feet
- Pull it apart so you have each side of your dipole
- Strip and solder one end of each wire
- On the crimp style BNC connector
- Wrap the soldered end around the shield collar
- crimp it and solder it to ensure a good connection
The center conductor will not be used on this connector!
- On the right angle connector
- Wrap the soldered end around the center conductor screw
- Tighten down the screw
- Solder it to ensure a good connection
- Make a right hand knot around the shield clamp to give a
bit of strain relief
- Clamp the shield connector down around the insulated wire
- Connect them together with the FFF BNC T
- Connect to your rig/analyzer with appropriate coax
- Tune/prune to appropriate length
- Finish off ends of wire with ring terminals
- Strip a bit of insulation off of the wire
- Tin the end
- Crimp on the connector
- Solder the connector
- Use "reuseable" zip ties to manage transport/storage of this antenna.
- Pick up a piece of 10-base-T RG-58A/U "Networking" Coax with Male BNC's at each end
while you're in Radio Shack. (Over with the computer stuff.)
- Obtain two lengths of nylon cord of a size that will easily go
through the eye of the ring connector. Used for tying off of trees, poles, etc.
- The bag I use has two side pockets. One half of the dipole goes in each side.
- With a small tuner such as the Emtech ZM-2 or LDG Z-11 you will most likely be
able to work 80M-70cm with this antenna. (I found I could use the ft-817 on
several bands as constructed.)
- I am not affiliated with Radio Shack or any other retailer.
WA2ZKD suggested the following (edited):
- The BNC connectors used are OK for on/near resonance and QRP
operation. When used at higher power-off-resonance, like with an
antenna transmatch, they may arc.
- For NVIS, an electrically long dipole may not do as well as a
dipole cut to frequency. This is because the long dipole may
"lobe up" and show directionality.
- The addition of a simple current balun, such as the W1JR with
ferrite on the feed coax, will help and cost little.
- On one vehicle I have a home-brew 1/4 wave whip for 6 meters.
It is connected to the HF/6 port of an ICOM 706mkII.
Disconnect one side of the dipole from the BNC T.
Slip it's ring terminal over the mobile whip.
Ensure a good mechanical contact.
Throw the end with the BNC up in a tree.
In some way support it so it's not in contact with ground.
Now you can work 80Meters. I checked into the Missouri
traffic net with this antenna and received 59 reports.
- Install Anderson Power-pole connectors at the appropriate
places in the wire so that you can make 80-6/2M dipoles.
You will have to tape/support the connections in some fashion.
If left un-taped/supported spade, bullet and anderson power pole connectors
will come apart under tension. (I have emailed Anderson requesting
that they manufacture a wrap of sorts that would provide strain relief
and lock a single connector together. In the mean time perhaps an overhand
knot will do the trick.)
- Using a small machine bolt, pair of washers, lock washer and nut,
connect the halves together at the ring connectors.
Plug end with center conductor into rig/tuner for a 160M 1/4 wave.
(Do something with the rig's ground connector for this configuration!)
Reports from Builders
- KC0IFL reports that he built this antenna for 20 Meters.
He succesfully used it with his K2 and ATU in an inverted L position from a second floor hotel room.