With my MTR project wrapping up, I thought I could retool the Par antenna to make a really tiny and lightweight EFHW even more minimal than the one I built before. The idea was to replicate the PAR matcher since it does not require a big, variable capacitor. Luckily someone had already torn into that black box and found what was inside. (that article is here) I stole his nice graphic depicting the circuit, it'll also take you to the article.
It is very simple: a 150pF shunt capacitor and a 9:1 transformer (3 primary turns, wound bifiliar, 27 secondary turns). The article mentions that the commercial unit uses an FT87-43. I built mine with an FT37-43 because that is the smallest I had on hand. The raw circuit built up is below:
Yeah its that small! |
I added an eyelet imbedded in the glue in case I need to tie off the end |
A couple of washers close up the feed point end and a #4 screw is held in place to connect the radiator
Lets get to the video already!
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