Hello All:
I have not been active since the VU4 folks provided the final country I
needed to "have 'em all worked." Now, there are 2 "new ones" I need. Having
had
some previous problems with obvious higher than normal SWR, I had arcing in
the Amp. that partially melted the tuning capacitor plates & some other
components, as well as arcing in my tuner in addition to the tuner NOT able to
tune
out the high SWR. The combination of equipment (Amp. & tuner) has been the
same for years. The Coax was replaced about 5-7 years ago. I previously melted
the original Balun supplied with the XA. A M2 Balun replaced the original
one. I brought the antenna down & re-checked ALL measurements before putting
it
back in the air, long ago. It has served well enough (thanks to almost always
having to use a tuner) over the years to have 'em all worked & confrimed,
previously.
Recalling the arcing problems I had previously, I checked the XA the other
day with a
MFJ-259 B & discovered the following resonant frequencies where a SWR
reading of 1.1:1 exists except on 10 Meters where the lowest SWR reading
obtainable
was 1.6:1.
20 Meters resonant at 16.4 MHz.
15 Meters resonant at 20.7 MHz.
10 Meters resonant (lowest point to resonance) at 28.4
The 2:1 SWR range width is as follows:
20 M - 335 KHz
15 M - 170 KHz
10 M - 1.01 MHz (there is also a 3.5 MHz 2:1 SWR curve at 34.5 to 38.0 MHz)
The M 2 Balun is about three years old ... and the KT-34 XA itself has been
in the air for the past twenty five (25) years! Despite its age, it has
obviously worked well & is testimony to the original design and materials
used.
This is certainly not a complaint about "not getting my monies worth" over the
purchase. Several matters & personal limitations prevented bringing the
antenna down sooner. It now appears it is indeed time for a new tri-bander?
If anyone has any ideas as to why the resonance points have shifted so
dramatically, I would appreciate the information. From ground level, using
binoculars, all appears to my eyes to be just like it has been for years &
years.
Birds of many species such as Red Tailed Hawks & Crows have, over the past 25
years, used the antenna as a stopping point.
"Yes" ... I'm certain many of you will simply say "just go buy a new
antenna. You've gotten more than your monies worth from that purchase 25 years
ago".
That sentiment is ever so true & I'm fully aware of that: thank you.
Sarcasm & less than positive comments and/or information are neither
invited, wanted, appreciated, or remotely desired. We can get enough
"contributors"
IMO in those fields on other, "more than controversial" matters on a myriad
of subjects rather easily.
Thanks in advance to all who may reply & contribute in a positive manner.
73 & Good DX.
Les, NN6K (RTTY Forever)
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