160m On An 18m DX Commander Mast

Comments · 32

• HA

  @Ham101live · 1 month ago

  Well done James.  Btw that field looks like the field Callum / M0XXT started with 😂😂😂😂 good DX 73

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• M8

  @M8KHC · 1 month ago

  The spirit of amateur radio right here. <br><br>Excellent video James.

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• VK

  @VK3ACU · 1 month ago

  Excellent video James, I&apos;ve been experimenting with the low bands myself. Have recently built a EWE antenna, it is really quite incredible being able to change directions. Even null out broadcast stations on the same frequency. 73

  1

• DA

  @David.M0TPT · 1 month ago

  Nice work, James. Love this video,

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• GT

  @gtretroworld · 1 month ago

  Interesting video there James. I had no idea Callum did 18m poles..thanks for the content..👍

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• MI

  @MirlitronOne · 1 month ago

  Hi James. These are good WSPR results for a compromised aerial on 160m at this time of year. It&apos;s hard to get beyond Europe!

  2

• MI

  @michaelmohr9700 · 1 month ago

  Nice experiemt! Thank for this video.....I&apos;m working on a Vertical for 160m to 30m on a 18m Spidermast.....for 160m I will use a Loading coil.....BR Michael

  2

• JX

  @JxH · 1 month ago (edited)

  In general, the radiation is emitted according to the current. Thus, with the well known standing wave on an antenna, the maximum current is at the bottom, while the top peters out as mostly voltage and next-to-no current. Therefore, it would generally be better to top load the vertical with a capacity hat - as opposed to bottom loading with a coil (which is less efficient as a radiator). 18m of height is already nearly half of a quarter wavelength, so perhaps a thin wire or two can be used from the top, like guy wires. <br><br>For maintaining 80m, a switch could be installed at the top, operated by pulling by a string. Perhaps a lamp switch with a pull cord could be adapted, or just keep tension on a microswitch. 🙂<br><br>Of course, in practice things still work even if not the optimum. Cheers.<br><br><a href="https://www.youtube.com/watch?v=LbEmaOKYRew&amp;t=180">3:00</a> You mentioned the same thing !! &nbsp;Cheers.

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• DX

  @DXCommanderHQ · 1 month ago

  40 x 16m? My goodness! That&apos;s more than I have! LOL - Anyway - just thinking James... How about putting a bigger coil - half way up instead of on the base..? Nice job mate!!

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• ST

  @StreakyP · 1 month ago (edited)

  Your good 160m SWR may actually be bad!.<br>10th wavelength antennas can work acceptably ( an ATAS120 is only a 1/10th of a wavelength on 20 &amp; 16&apos; red slugs can be matched onto 40 with proper matching at the base). <br>1/10th of a wavelength whip is low radiation resistance plus a shed load of capacitive reactance. <br>To match a low resistance (alone, disregarding the reactance for now) an LC match directly at the antenna base can be used.. C in series with the wire up the mast &amp; L across the coax terminals... BUT BUT BUT... Your antenna already has too much capacitance so you need to bring that down to the required match capacitance by adding L in place of the matching C ( an LL match where the antenna capacitance brings it back to being an LC match). I&apos;ve done this LL match at the base of 16&apos; red slugs for 40m &amp; it works fine).<br>You have the 10th wave whip &amp; put on the base loading L which is good for killing the antenna capacitance but it should now be just pure resistance... But LOW resistance so the SWR should be bad. As it isn&apos;t bad, it is good, that suggests you might have some loss resistance in there taking the power instead &amp; giving you the &quot;good SWR&quot;.<br>Try measuring the R-jXc of the raw antenna then pop that figure into one of the on-line match calculators to give you the L Series &amp; L shunt value to give a proper match at the base.

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• JA

  @JayN4GO · 1 month ago

  Try running the wire straight up and back down to the fence in the back. You can put the coil at arms reach. This will greatly increase the efficiency of the antenna on both bands. 127ish feet total. Looks like you have the room there. Maybe bring the end down to a t post in the field. If you want more efficiency, try making the wire 170 ft and use a mica capacitor at the feed point. 500pf. This makes the antenna a 3/8 wave inverted L with the current maximum at the top of the mast and it will love those radials. Just a thought. Nice job

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• MI

  @MicheálÓB · 1 month ago

  D-layer absorption sucks the life out of 160m in the daytime but that goes pretty much as the sun goes down. In the summer there&apos;s typically more atmospheric noise to contend with so the winter months are likely to be significantly better. If you can get a capacity hat on the vertical and move the loading further up it that might make a difference but 160m antennas often behave counter to expectation, at least they do for me!

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