WB4IUY's Random Blog

I've been in Amateur Radio since 1974, and still find new and interesting things to do. I like to build, restore, and operate on the air. This is a blog of various info about my Ham Radio operations and activities, projects, and opinions. Visit www.WB4IUY.net for the lowdown at WB4IUY.

Tuesday, April 17, 2018

6M Yagi Rebuild, 2nd Evening...

I got in from work a little before dark today, and decided to work on the 6M yagi project a bit more. I spliced the broken sections with 1/2" type M hard copper from the hardware store... This stuff is stronger than the aluminum it's repairing, the short sections won't add much weight to the yagi, and it's CHEAP :-)  I've repaired antennas like this that held up 20+ years and are still working.

The center sections of the elements were supposed to be 48" long, each. They were mostly broken right around the boom attachment point. I cut out the crimped sections, cut the copper long enough to extend into the aluminum 3" on each end, and restored the center sections to 48" long. I drilled the tubing and secured it with 1/8" pop rivets, then used the low temp flux core aluminum brazing rod to solder the parts together securely for a continued good electrical connection. The brazing rod comes from Home Depot, and is the type that melts about 700 degrees F... This allows the use of a small torch to handle the job. 

After the elements were repaired, I did a quick mock up in the yard... see the last pic. Day 3 should allow me to get the boom mounted on my test tower, and get it marked up for test assembly. Here's a few pics...

Installing the splice sections, drilling, and pop riveting.  
 
Checking for straightness, after returning from the redneck tubing straightener, described in my previous blog...
 
Cutting out the damaged sections...

Checking more elements for straightness...

The matching section is in pretty foul condition...

 I soldered the copper splices into the aluminum elements for continued good electrical contact...

Propane Torch and low temp aluminum flux core rods...

Another element after soldering the copper splice to the aluminum element. 

A quick mock up in the back yard to get a feel for the element layout. It's beginning to look like a yagi, again :-)


Dave WB4IUY
http://www.WB4IUY.net