Steve,
from what you write I presume you have the 269, not the 259B (which =
works fine).
As you are the only person who answered me, if you have time could you =
please re- check your 269 by loading it with a resistor in the range 150 =
to 200 ohm, verifying that the reactance (X) indication remains nearly =
zero when varying frequency in range 2 to 10 MHz.
The only 269s I know are mine and the one tested by ARRL on QST. And =
both of them have a problem. So, if yours does not show that problem, =
then I have some hope
73
Tony I0JX
"Steve Nosko" ha scritto nel =
messaggio ...
I did some playing with mine after getting it, but didn't see anything =
like
this. I did pretty much the same things, as I recall.
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HOWEVER, I did notice that going into the advanced mode and setting it =
for
ZO of 75 ohms that is didn't report SWR correctly (should be 1:1 w/75 =
ohms
attached and it still said 1.5 as though it still was thinking 50 =
ohms). I
called and the "tech" who answered clearly didn't understand (said =
return
it) and I elected to drop it since it worked ok otherwise.
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I'll try to find some time to re-check this issue.
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73, Steve, K9DCI
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"Antonio Vernucci" wrote in message
...
This post may be a bit OT, but I believe this is the forum where I can =
get
some useful information.
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I have an MFJ-259B antenna analyzer which works fine. I also have an =
MFJ-269
(the one also working on UHF) which instead gives me odd results on =
the HF
bands.
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I then sent the 269 back to MFJ for warranty repair, and when it came =
back
it had exactly the same problem, despite I gave them a very detailed
explanation of the problem.
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In summary the problem is the following:
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- loading the MFJ-269 with 50 ohm all is OK (it gives R=3D50, X=3D0)
- loading it with a different value, say a small 200 ohm carbon =
resistor
with very short leads, it gives R=3D200, X=3D0 at around 10 MHz but, =
LOWERING
the frequency (e.g. down to 3.5 MHz), it progressively shows an higher =
and
higher X value. This result is clearly wrong as a resistor having 0
reactance at 10 MHz cannot show reactance at 3.5 MHz. This is =
confirmed by
the the fact the MFJ-259 loaded with the same resistor shows X=3D0 at =
3.5 MHz!
So, no question about that!
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Interesting to note that the MFJ-269 Product Review on QST magazine =
(May
2005 issue, Table 3) shows EXACTLY the same problem! A 269 design =
problem
which does not exist in the 259?
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Reading the MFJ-269 factory calibration procedure (I have a copy of =
it),
they instruct the operator to adjust the instrument at 10 MHz. And at =
10 MHz
it works fine!
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Has anyone carried out a similar test?
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Thanks & 73
=20
Tony I0JX (also K0JX when in the US)
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