I think that I missed the original message about antenna matching problems
but I will make comments anyway. I do not know if the MFJ antenna in
question has radials or not. That could make a difference if it is fed by
coax cable. I have a Hustler 6 BTV which is ground mounted. (I have
similar space limitations) I initially tried the antenna with a RG-8 feed
line and it seemed to be somewhat well behaved but did exhibit some weird
characteristics. I hate to admit this on the reflector but I must be
honest - - - I read the instructions! There is mention of a potential
problem if the antenna is used in the ground mount, without radials,
configuration. This is because the shield of the coax is connected to where
the radials would connect. This causes an excess amount of RF current in
the shield since it ends up taking the place of the non existent radials. I
tried the suggestion in the instructions - - - I made two coils in the feed
line. The coils are 10 turns on a 6 inch diameter. I did not have a
convenient 6" item to use as a form so I simply formed a 6" loop which I
secured with cable ties. I proceeded to make the 9 remaining loops and
secured the whole thing with more ties. It worked quite well but was
certainly more time consuming than using a form. Well anyway I have one of
these coil things located about 2 feet from the base of the antenna and
another one just outside the shack. (about 6 feet from coil to rig) These
coils made a HUGE difference. Apparently the problems I WAS having were
not, as I thought initially, due to antenna problems! They were due to a
significant amount of current on the shield of the coax! Problem solved!
On another matter - I strung up a 100' piece of wire and intended this to be
a SWL antenna only. I tried end feeding it with a MFJ 941E tuner. I was
pleasantly surprised when I was able to easily adjust for less than 1.5 : 1
on all bands from 75 to 10 and especially after making a contact in Eastern
Europe while running only 25W!!!
73's; BILL
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