This week, I decided I’d try out some new LMR-240uf jumpers that had arrived. Most of the jumpers I use in my portable station are 10′, either the LMR-240 (stiffer/solid center) or the LMR-240uf (UltraFlex, stranded center.)
For a few years I’ve really loved the stiffer LMR-240 and it’s never been a problem. However, at a friend’s insistence I went ahead and made some LMR-240uf jumpers. I’ve yet to notice a big difference however, I’d probably use the solid center if I was making some record-breaking attempt.
Since there was a LilacSat-2 pass rising, I decided to test the jumpers on that pass from my patio, facing east. Here’s the catch: I wanted to use a single Yaesu FT-817. Yes, it would be semi or “half” duplex (not my favorite/recommended,) but it was a good chance to test both jumpers. Before I used them on RF, I did do a quick continuity check with my VOM to make sure the cables had no short.
How can I test both jumpers on the FT-817 without using the Arrow diplexer you ask?
The FT-817 has two antenna ports. Simply configure UHF for one port and VHF for the other. You do this by going to the band and selecting the antenna in your menu: Front or Rear.
Since both jumpers are terminated with BNC males, I did need to use an adapter on the FT-817’s rear SO-239. It’s not my recommendation to use adapters since they are prone to failure and can sometimes be lossy (especially cheap ones.)
All in all, it was a quick and easy test. I made 3 contacts on this pass: Tennessee, Ohio, and Colorado.