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Technical Topics => Equipment => Topic started by: ChrisSmolinski on July 16, 2020, 1312 UTC

Title: 20mb and 10/11mb folded dipole antennas
Post by: ChrisSmolinski on July 16, 2020, 1312 UTC
Both antennas are oriented roughly NW/SE for some directivity to the NE to Europe. 

They're both made with 300 ohm ladder line into a 4:1 balun and then RG-6 (75 ohm) coax.  I find folded dipoles tend to have a slightly wider bandwidth than those made with regular wire.  There is a section of rope that runs in parallel with the ladder line, ever so slightly shorter in fact, so it takes the stress, not the ladder line.

Yes, the 20mb dipole is lower, I may try to launch a higher rope with the Big Shot and see if I can improve that  :)

(https://i.imgur.com/SC06cwU.png)
Title: Re: 20mb and 10/11mb folded dipole antennas
Post by: Brian on July 16, 2020, 1558 UTC
Just going by my experience of folded dipoles on band 2 VHF, I would say that the bandwidth is considerably better. I've been toying with the idea of making one for HF transmission but I'm not sure if I can build one to handle the power I would be using.
Title: Re: 20mb and 10/11mb folded dipole antennas
Post by: ChrisSmolinski on July 16, 2020, 1644 UTC
Just going by my experience of folded dipoles on band 2 VHF, I would say that the bandwidth is considerably better. I've been toying with the idea of making one for HF transmission but I'm not sure if I can build one to handle the power I would be using.

I've transmitted on the 20m dipole, 100W PEP SSB. Not sure how it would do legal limit.