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.

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.


I'll try to find some time to re-check this issue.

73, Steve, K9DCI


"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.

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=50, X=0)
- loading it with a different value, say a small 200 ohm carbon resistor
with very short leads, it gives R=200, X=0 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=0 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!

Has anyone carried out a similar test?

Thanks & 73

Tony I0JX (also K0JX when in the US)