9 Responses

1. Mitch Cox

   January 25th, 2016 at 9:30 am

   1

   This antenna was first designed by N4MXZ who was living on a small lot and wanted a good signal on 160. I simply adjusted the length so you could use it without a tuner on 160, 80 and 40 meters.

2. RD Bentley

   January 25th, 2016 at 3:33 pm

   2

   Thank you Mr. Cox for the clarification and the additional information. With your permission I will keep the post active, because I do enjoy the study of antennas. It’s quite an honor to hear from you sir. All the best. 73 de KI4KQD

3. Jim Dugger (N4MXZ)

   March 16th, 2017 at 10:11 pm

   3

   Indeed

4. http://ohww.co.uk

   August 1st, 2017 at 10:49 am

   4

   Appreciating the time and effort you put into your blog and detailed information you present.
   It’s great to come across a blog every once in a while
   that isn’t the same outdated rehashed information. Wonderful
   read! I’ve saved your site and I’m adding your RSS feeds to my Google account.

5. The 80 Meter Doublet With 300 Ohms | ON THE SQUID

   November 5th, 2017 at 8:24 pm

   5

   […] Big Zapper has gained popularity with many hams. This is another variation definitely worthy of […]

6. Ray Lewis

   March 18th, 2019 at 11:11 pm

   6

   Has anyone tried this at half the length for 80 through 6 meters? I just do not have the space for the 96 feet length. Thanks, Ray AA4EZ

7. Hiram Vazquez

   March 4th, 2020 at 8:51 pm

   7

   The photo says “no balun needed” but the description says to use a 2:1 balun. If I use a 2:1 balun will it only be resonant on 80 and 160?

8. Rich Evans

   April 14th, 2020 at 3:04 pm

   8

   @Mitch Cox – thanks for tweaking this design! I am just shy of a 160m 1/2 wave with some creative routing through my trees that leeches onto a neighbor’s tree who is not in favor of that. I think this design slightly modified will work. if this were an L shaped antenna, redirected 90 degrees at the feed point, do you think performance would be about the same? I will also have it higher than the suggested 40 feet, it will be at least 85 feet high and maybe a little higher in the top of several oak trees (thanks to my home brew air cannon). I’m just getting back into the hobby after 40 years and any advice you can offer is greatly appreciated! Rich KO4BLW

9. Mitch Cox

   May 27th, 2020 at 2:23 pm

   9

   The Zapper will work but i have found it does not work very well if any of the measurements are changed. You can shorten the ladder line to fine tune it but any other installation not as pictured will not work as well. It can be installed as an inverted V but again it does not tend to work as well on the top band. The best advice i can offer is put it up as you suggested and see how it goes. You will be heard but it may not give you the 100 ohm impedance on every band as it would installed as pictured.

   The 2:1 balun installed in reverse will give you a very good match on 160 meters without the need for a tuner. The Zapper is very close to 100 ohms input impedance on every band except for 160 which is around 25 ohms in most installations.