I have been thinking about making a couple of minimalist EFHW antennas with SMA connections for use with the (tr)uSDX. After weeks and weeks of out-of-stock conditions for my preferred kit, I ordered up some parts and started to make one from scratch. Starting with an FT50-43 toroid core, I wound the 49:1 unun:
![](http://driftlessqrp.com/wp-content/uploads/2023/09/IMG_20230904_154223-768x1024.jpg)
The SMA connector on the (tr)uSDX seems to be well supported by the case, and reasonably sturdy, but to protect it further I bought some 6 inch SMA jumper cables and cut one in half to make a flexible input connection. RG-316 fits neatly in the two 1/8″ holes I drilled to form a strain relief:
![](http://driftlessqrp.com/wp-content/uploads/2023/09/IMG_20230906_165045-768x1024.jpg)
I bought a bunch of prototyping boards of various sizes years ago at a hamfest and I am slowly using them up, one by one. Having this one saved a lot of time and effort!
![](http://driftlessqrp.com/wp-content/uploads/2023/09/IMG_20230908_195533-768x1024.jpg)
![](http://driftlessqrp.com/wp-content/uploads/2023/09/IMG_20230909_150903-1024x768.jpg)
![](http://driftlessqrp.com/wp-content/uploads/2023/09/IMG_20230909_151109-768x1024.jpg)
![](http://driftlessqrp.com/wp-content/uploads/2023/09/IMG_20230909_151316-768x1024.jpg)
![](http://driftlessqrp.com/wp-content/uploads/2023/09/IMG_20230909_151625-768x1024.jpg)
![](http://driftlessqrp.com/wp-content/uploads/2023/09/IMG_20230909_153851-768x1024.jpg)
I’m planning on using the (tr)uSDX as the primary test instrument, running it at low power from the USB connector. Watch for the report soon!
![](http://driftlessqrp.com/wp-content/uploads/2023/09/IMG_20230910_183524-1024x768.jpg)
I hope you found this interesting; if you have any questions or comments feel free to post them below, or email me. Thanks for visiting driftlessqrp!
Leave a Reply