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Fair Rite Snap It cores for mic cables (~6mm)

Fair Rite Snap It cores for RG-8 size cables (~13mm) OD 

Fair Rite Mix 31 FT240 size cores

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5 Banding the 20m 1/4 wave Junk Pile Vertical

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One nice  spring day in 2019, my grandson and I went outside for a walk around the property.  I happened to notice a piece of aluminum tubing I had lying beside a shed.  On further investigation I realized it was half of a 20m beam element that another ham had left behind after a field day.  It had been a half wave dipole for the event and he told me to just keep it. I asked my grandson, 6yr old at the time if I remember correctly, if he would like to help me build an antenna.  His reply was a curious, "What's an antenna papa?".  So, we had the unforgettable experience of building a ground mounted 1/4 wave 20m vertical together. A few days ago I got the idea to add more bands to this antenna.  I did some digging around and found some wire, purchased a few pvc fittings and hose clamps, and started putting additional 1/4 wave elements for 17m, 15m, 12m, and 10m.  I know, some of those bands are going to be very inefficient ground mounted, but what t...
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1:1 Current Choke

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    Up to now, I had fed most of my antennas directly with coax.  Doing eSSB I wanted to keep as much common mode (RF) out of the shack and help keep the RF on the antenna where it belongs anyway.  I suppose it is good engineering to do this anyway, so I started looking into ways of doing this. The 1:1 choke is the device, but there are different ways to achieve this.  The infamous "ugly balun" (Or is it really an unun?) is one way.  It requires no additional parts, just wind the coax at the antenna on a form.  12 turns of RG-8 on a 5 inch form is about 18μH at 160m. That means just over 15 1/2 feet of coax is used to make the choke.  With prices usually running about $1.20/ft, that's around $20 in feedline and you still need the PVC form and end caps to make a nice choke that will last.  My estimates as of January 2022 put that at about $30.  It is also a considerable amount of weight at the center of an antenna.  200ohm of impedan...
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