<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div dir="ltr"></div><div dir="ltr">Great tips everyone. </div><div dir="ltr"><br></div><div dir="ltr">Willie, the adjustment calc here </div><div dir="ltr"><br></div><div dir="ltr"><a href="https://wireless-girl.com/Projects/Antennas/AntennaCalc.html">https://wireless-girl.com/Projects/Antennas/AntennaCalc.html</a></div><div dir="ltr"><br></div><div dir="ltr">May be of some use. Rest of Janis’s site is interesting too. </div><div dir="ltr"><br></div><div dir="ltr">In my experience, putting an antenna wire against wood causes it to look electrically long. 468/7.15 MHz = 65.5’ but up on the roof material you may find it needs to be shorter to work. </div><div dir="ltr"><br></div><div dir="ltr">Is there a reason you don’t want it between trees (a condo)?</div><div dir="ltr">Andy</div><div dir="ltr">KA1GTT</div><div dir="ltr"><br></div><div dir="ltr"><br>On Sep 4, 2020, at 12:02 PM, Bruce Anderson <<a href="mailto:w1lus@hotmail.com">w1lus@hotmail.com</a>> wrote:<br><br></div><div dir="ltr">
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Hello Willie</div>
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If you plan to just use SSB tune for the top of the band.</div>
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If just CW or digital tune for the bottom of the band.</div>
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Tune to the middle for both.</div>
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If you want to fold back the ends while adjusting the length you must connect the end of the folded back portion to the antenna wire.</div>
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If you are using insulated wire just strip the last few feet so you can connect the folded back portion.</div>
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Also, the loop formed by the folded back wire makes it easy to connect whatever you are using to hold up that end of the antenna.</div>
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I don't use antenna insulators, just rope to hold up my antennas.</div>
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Once you have it tuned to your satisfaction either cut off the folded back section or solder the connection to make it permanent. </div>
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Bruce</div>
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W1LUS</div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> bars <<a href="mailto:bars-bounces@w1hh.org">bars-bounces@w1hh.org</a>> on behalf of Mike Raisbeck via bars <<a href="mailto:bars@w1hh.org">bars@w1hh.org</a>><br>
<b>Sent:</b> Friday, September 4, 2020 6:14 AM<br>
<b>To:</b> <a href="mailto:w_smith@compusmiths.com">w_smith@compusmiths.com</a> <<a href="mailto:w_smith@compusmiths.com">w_smith@compusmiths.com</a>>; <a href="mailto:bars@w1hh.org">bars@w1hh.org</a> <<a href="mailto:bars@w1hh.org">bars@w1hh.org</a>><br>
<b>Subject:</b> Re: [bars] 40M Dipole?</font>
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<div><font size="2">Hi Willie,</font></div>
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<div><font size="2">A couple of observations:</font></div>
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<div><font size="2">1 - it doesn't need to be super straight. any angle greater than 60 should do it.</font></div>
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<div><font size="2">2 - if you have choices on which point can be the highest, go for the center. The center portion of the dipole carries most of the current, so the higher the better.</font><br>
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<div><font size="2">3 - shoot for the middle of the band - it's a squeeze, but you might get most or all of the band at less than 2:1 SWR. If you have a tuner on your rig, it hardly matters at this fequency<br>
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<div><font size="2">4 - depending on where your coax enters the house, you have the opportunity to base feed the whole thing as an 80m vertical</font></div>
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<div><font size="2">5 - might as well have a 20m dipole on the same feed points as well. That way you get 20. Though the SWR may be a bit over 2:1, you will get 15m as well.</font></div>
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<div style="font-family:arial,helvetica; font-size:10pt; color:black">-----Original Message-----<br>
From: William Smith <<a href="mailto:w_smith@compusmiths.com">w_smith@compusmiths.com</a>><br>
To: <a href="mailto:bars@w1hh.org">bars@w1hh.org</a><br>
Sent: Thu, Sep 3, 2020 7:11 pm<br>
Subject: [bars] 40M Dipole?<br>
<br>
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<div>Hi All,
<div class="x_yiv6847165435"><br class="x_yiv6847165435">
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<div class="x_yiv6847165435">As I mentioned last night during the Zoom meeting, I'm looking at building a 40M dipole out of some wire, insulators, and an SO-239 connector, using essentially the instructions at:</div>
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</div>
<div class="x_yiv6847165435"><a rel="nofollow" target="_blank" href="https://dcasler.com/2011/02/17/ham-radio-40-meter-dipole-your-first-antenna/" class="x_yiv6847165435">https://dcasler.com/2011/02/17/ham-radio-40-meter-dipole-your-first-antenna/</a></div>
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<div class="x_yiv6847165435">I'm hoping to stretch it out across the roof peak of my house, which has lots of space:</div>
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<div class="x_yiv6847165435"><img id="x_yiv68471654351B7903C8-1BD5-48EE-9ECB-A083B8FE7451" width="727" height="508" data-outlook-trace="F:1|T:1" src="cid:Qeeb92KwmnV1Z9Pts5NH"></div>
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<div class="x_yiv6847165435">The ridge of the larger side is 40 feet, and the smaller side is 25 feet, so 66 feet ought to be do-able.</div>
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</div>
<div class="x_yiv6847165435">I have a couple of questions for the experts:</div>
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<div class="x_yiv6847165435">1) Does it make much difference if the antenna is straight? I might do something like:</div>
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<div class="x_yiv6847165435"><Screen Shot 2020-09-03 at 6.59.22 PM.png></div>
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<div class="x_yiv6847165435">To stay away from the ridgelines, where I know there's a lot of wiring (the point of the "Vee" is where I have a couple of antenna poles.)</div>
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<div class="x_yiv6847165435">2) Obviously I want to start out long and shorten the wires, so as to avoid the "I cut it three times and it's still too short!" problem, but I'm not sure if I have to cut the (insulated) wire at the ends, or if I can wrap it back
around itself (which would allow me to lengthen it if I overshoot).</div>
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</div>
<div class="x_yiv6847165435">3) Should I aim for one end of the band or the middle? Or is it going to be pretty good throughout the band?</div>
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</div>
<div class="x_yiv6847165435">Is there anything else I should know before I start?</div>
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<div class="x_yiv6847165435">Many thanks in advance!</div>
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<div class="x_yiv6847165435">73,</div>
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<div class="x_yiv6847165435">Willie</div>
<div class="x_yiv6847165435">N1JBJ</div>
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