Finishing touches to the minimalist EFRW

The end “insulators” are thin slices of 1/2″ OD HDPE water tubing – I drilled a 1/16″ hole, passed the wire through, and tied a knot in it. It’s just enough isolation for QRP power levels, and handy to attach a cord for hoisting.

Last weekend, when I put the little EFRW together, I searched the radio room for the assorted heatshrink tubing collection and came up with nothing. I’m sure it will turn up one of these days …

Twelve dollars and three days later, I had a new box of clear, glue-lined tubing, and I was ready for the final step: covering the 3 mm connectors I attached to the leads of the transformer.

Lighters leave smoke marks on the tubing, and can actually set it on fire. The hot wind of a heat gun can easily blow little bits of tubing around. These days, my preferred method of heat-shrinking employs the radiant heat of the electric stove in the kitchen.

I generously applied foil to the wires to prevent thermal misfortune!

Speaking of heat resistance, the next time I build one of these (and there will be a next one!), I think I will substitute silicone-covered wire for the PolyStealth that K6ARA includes in the kit. Nothing wrong with the PolyStealth, it’s good wire, but the insulation didn’t seem to like the heat of shrinking the tubing.

I am omitting a photograph of the cooktop glowing a dull red; and the actual procedure of shrinking requires two (or more!) hands, so there are no pictures, and you will just have to use your imagination for this part.

Close-up of of a nice shrink job with a tasteful crimp added.

I like to squish the tubing with long-nose pliers while it’s still hot, to be certain that the glue lining gets a good bond to the wire.

Back upstairs to the long hallway with the tape measure to verify the lengths.

Measuring to the transformer , 7 feet, 7 1/2 inches; 1 1/2 inches over.

22 feet 10 3/4 inches overall; subtracting the center part, 15 feet 2 1/4 inches.

So an inch and a half too long on one end, two and a quarter over on the other; it looks like I cut the wires pretty accurately, the overage seems to be in the leads on the transformer. If that is a problem when I tune it up in the field I can trim as needed.

When I took the tape off of the wire bundles to lay out the antenna they immediately got severely tangled up, so I knew I would have to come up with something to wind them on. I found a little thing that was meant to hold a pair of earbuds …

And there it is, ready to go in the radio bag! Weight, 1.1 ounces (31.2 grams).

I was passing through Hillsboro yesterday, and saw this across the road from the brewery. Not sure who, or what, or why, but it looked cool!

Thanks for visiting driftlessqrp!