>
>Esteemed Reflectees,
>I just picked up an MFJ 259 (not the newer "B" version). Was
wondering if
>any of you all have tried it as is, and, with the optional "grid
dippper"
>add on.
>
>Comments?
Hi, Lane.
I bought the grid dip 'add-on' kit for the 259 back when I was
refurbishing an old A3. Compared with a real GDM, the 259
sucked. My GDM is a B&W Model 600. It worked super to identify
the resonant point of each trap. The MFJ placed in the same
position failed miserably every time to even indicate anything
resembling a dip....even when I knew where the dip was supposed
to be.
Now, it may be useful in some other grid dip venue, but this was
a pretty static setup -- the trap was placed between two 2x4's,
the GDM was pushed up to the trap's element segment and tuned
until a dip was found. Simple. The measurements were consistent
and repeatable. Never saw a thing with the MFJ.
I did do something that was kind of interesting, but really not
necessary. After getting the dip on the B&W, I put the two GDM's
coil-to-coil and tuned the MFJ for a dip. When I got that I was
able to read the 'exact' frequency of resonance....I
think......for whatever that's worth, the MFJ did work in this
regard.
I do swear by (not at) my MFJ 259 when it comes to doing antenna
adjustments, though. The thing is a real timesaver.
73,
dale, kg5u
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