This post may be a bit OT, but I believe this is the forum where I can =
get some useful information.

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.

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.

In summary the problem is the following:

- 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!

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?

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!=20

Has anyone carried out a similar test?

Thanks & 73

Tony I0JX (also K0JX when in the US)