Andrews 1/2" Superflex FSJ4-50B

[N4GIX]

I was gifted with the remainder of a 1000m spool of genuine Andrews 1/2" Superflex FSJ4-50B heliax left over from an Illinois State tower upgrade. There were quite a few leftovers of various sizes including some 1.5" Andrews.

In any case I now have a LOT of 1/2" heliax taking up room in my garage. A GMRS group I belong to was planning to put yet another repeater up and needed at least 200'. Well, I wound up with far more than actually needed...

The cable is marked every meter with the length to that point. The loose end is marked 1219m and the tail end is marked 1414m. The difference is at least 195 meters, or in feet ~640'...

Now I just have to figure out what I'm going to do with the 400' remaining after I donate 200+ feet to my group!

 

[vagrant]

I use FSJ4-50B for a 100' run on HF freqs and a 50' run of it for an APRS RX antenna at 144 MHz. While it is slightly better than LMR-400, it is more to wrestle with.

I know it was gifted, but why not purchase 1 1/4" or 7/8" Heliax on a 200' run for GMRS freqs? Is the coverage area a small town?

 

[N4GIX]

The short story is money. The club simply does not have enough to pay for tower space, which given the Chicago area is considerably expensive. One of our members used to be one of the engineers at WGN's studios in the Sears Tower, and had this repeater just below the roof of the tower. As you can no doubt imagine, the footprint was HUGE! But when he left to go work for NBC he had to remove the repeater(s). He had two of them up there!

The cable is worth around $1k at wholesale prices. Coverage was to be at Chicago's northside Arlington Heights a few miles west of the current repeater on Parkridge Hospital. Unfortunately our site study of the proposed free tower space, intermodulation interference analysis found a direct 3rd order product hit that would adversely impact the 650 repeater at the NWCD Arlington Heights tower site. Further analysis determined that this same problem would exist at any NWCD tower location.

So until another site is found, the proposed new repeater project is on hold...