I'll add my vote for these. I can't remember if I have already mentioned
this here or not--one of my antennas is a low 88' dipole fed with 600 ohm
open wire feedline and a balanced tuner. It works great. I use this all
the time now on 40 and 80 instead of my gap vertical. My tuner is a Bliss
Z Matchmaster. it uses a pair of 30 microhenry roller inductors and a 1000
pf vacuum variable cap with a coax 1:1 current balun between the 50 ohm
feedline from the tx and the tuning components. it takes all the rf I can
throw at it (1.2 kw p.e.p.). my open wire feed is about 40' long. the
unbalanced line to the tuner is about 15' long. Mine is the 1.5 kw manual
transmatch which I guess is not made anymore since it is not mentioned on
John Bliss's website:
http://airwaterkinginc.purification.com/bzmmremotemotor.html
that's too bad because it was a lot less expensive than the motorized ones
he makes now. The Matchmasters are the Cadillacs.
Palstar has begun making a manual balanced tuner--I think it is the
AT1500BAL or something like that. It seems to have a few drawbacks: air
variable cap (however their inductors have higher max values than the Bliss)
but the bigger problem is, unless I'm mistaken, that they use a ferrite
balun which I think could saturate. OTOH, the Palstar is closer to a
typical manufactured tuner price.
It is probably possible to make one of these and save a lot of money. I
plan to extend my dipole to make a loop.
Rob Atkinson
K5UJ
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