[Johnson] 275 watt Matchbox Coil Setting

[Richard Peterson]

Congratulations. I am afraid you may have discovered the dirty little secret 
of the Matchboxes. They will not handle very large impedance excursions. I 
owned one and had the same problem, and even though the M-Box is a nice, 
balanced tuner, today's common T networks, either high- or low-pass, will 
match a much greater range -- but they are not balanced. They use baluns to 
attempt to achieve balance, with mixed results, I suspect.

Back in the days of Matchboxes, there was a thing called "tuned feeders," 
and feelines were of certain lengths (as were antennas, of course). If you 
hit the old ARRL Handbooks, you will find excellent tables on feedline 
length. Else, a stock Matrchbox can be failry frustrating. I sold mine, went 
to a home-brew high-pass T, and have been able to load anything and 
everything. Life is good. I don't miss the Matchbox.

Now, be prepared for a lively debate -- this is an interesting and complex 
subject. And there are guys out there (but not a lot) who have thrown up a 
random piece of wire and a random length of feedline and had good luck with 
Matchboxes.

Richard
WB5NEN