Total posts : 45366
Yves. The expert that explained the AM25 loading problem to me said that account it has a fixed 50 ohm untuned output that it would work well with a quarter wave antenna ie your long wire, yet wouldn’t tune to the lower impedence of a 3 meter base coil loaded antenna, so it looks like you and I are looking for the same solution. One of our knowledgeable people recommended that I connect the antenna before the 7 element harmonic filter at the output, that being the 3 donut shaped coils and capacitors connected to ground between them. I had already tried this and wiped out the next door neighbor’s TV reception. He also suggested a buffer of some kind, yet I haven’t gotten there yet. Another knowledgeable person said that the high Q of a base loaded 3 meter antenna would tend to suppress harmonics yet that didn’t work with the AM25 with its harmonic filter disconnected.
Neil, Thanks for the suggestion. That second winding and grounding one end of the coil may be something to work with. I’ve tried the variable cap from top to bottom of the SSTRAN tapped coil while connecting the xmtr ant to various taps without getting any good resonance point. JimB