A Two Dollar Helical HF Portable Antenna

NOTE: this web page was written in 2001. Prices have gone up considerably since them. This antenna was created as a fun project to illustrate that you don't have to spend a fortune to enjoy amateur radio operations. It is NOT  to be considered as an efficient antenna, or even a good one. Consider it a bootstrap device to get you started. For more information on better antennas, please get a copy of Practical Anenna  Handbook by Joseph J Carr, The Antenna Book by ARRL or any of the dozens of antenna books available. Please do not ask for clarification or optimization ideas. Use it for fun and graduate to a better antenna as you grow in the hobby.

Here’s an easily transportable vertical antenna for 20 meters collapsible to 4 feet that costs about $2.00 to make.

This was created as a fun project to demonstrate how to enjoy operating HF in the field with a home-made portable antenna without spending a ton of money.

Bev AH6NF (YL) made this antenna, tuned and ready to operate in less than one hour.

The design is a continuously loaded, helically wound vertical antenna with a three-foot stinger. The stinger folds along the four-foot mast for storage. Here’s how to make one.

Materials:

1. four feet of ½ inch white PVC water pipe (10 ft @ $1.29 = 4 feet for 52 cents)
2. 30 feet of 14 gauge insulated electrical house wiring (2.7 cents per foot = 30 feet for 84 cents)
3. 3/32 inch diameter brass brazing rod, 3 feet long ($8.00 per dozen = 67 cents each)
4. misc. junkbox stuff
• number 8 screw 1-1/2 inch long
• number 8 nut
• two small washers
• optional disconnect
• optional ring lug
• any junk wire 15 feet long for counterpoise (four pieces would be better)

Total cost = $2.00

Steps:

1. Cut 4 foot length of plastic pipe
2. Drill 3/32 hole through pipe 2 inches from one end (this is the bottom)
3. Drill 3/32 holes through pipe 2 and 3 inches from the other end (this is the top)
4. Push wire through the hole 3 inches from the top extending about 2 inches from the other side
5. Wrap the remainder of the wire, coiling it tightly around pipe toward the bottom
6. Push other end of the wire through the hole at the bottom extending about 2 inches
7. You now have a helical winding on a plastic pipe
8. Strip ½ inch from the top end of the wire and wrap it around the screw
9. Insert screw in the top end hole 2 inches from end, extending out the other side (photo-1 / 45KB)
10. Insert washer over screw
11. Form an eye on the end of the brass rod and place it over the screw
12. Insert second washer over screw
13. Insert nut onto screw and tighten until very snug (photo-2 / 61KB)
14. The brass rod should swivel from parallel to the winding to the stinger position
15. Make a small loop at the end of the brass rod as eye protection (photo-3 / 17KB)
16. If desired, attach a disconnect to the bottom wire (photo-4 / 48KB)
17. Attach a coax to the bottom wire
18. Add counterpoise / radials of any spare wire from junkbox – preferably 15 feet long (1/4 wave) to ground connection of coax
19. Mount on something vertical, extend counterpoise wire on ground
20. Connect coax to antenna analyzer or HF rig
21. Tune to desired 20 meter band
22. If on HF rig, use LOW POWER CW setting
23. Key and check SWR – expand and/or contract winding to get desired minimum SWR
24. If desired, tape winding in place after tuning.
25. That’s it ... enjoy
26. Photo of completed antenna with stinger folded for storage(photo-5 / 54KB)

ha-top2.jpg top screw connection 44.93 Kb

ha-top1.jpg stinger attachment 60.01 Kb

ha-tip4.jpg eye protection 16.63 Kb

ha-bottom3.jpg optional disconnect at bottom 47.02 Kb

ha-folded5.jpg antenna with stinger folded 53.75 Kb

 

Bev AH6NF and Jim WH6GS , HF Day, Sept 2001 

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