Richard,
You are so right about that static issue. I even seem to remember the Rig
Experts manual says to short the antenna leads together to remove any static
build up before connecting the analyzer. I think that was why I wasn't too
impressed with my MFJ-259b. Probably my own fail when I first got it. But I did
seem to get some pretty Squirrely results that didn't reassure me that it was a
solid performer. Now look how it saved the day. But at least my Rig Experts is
back in operation after correcting a poor solder joint on the SO-239 connector.
Terry
KI7m
> On June 10, 2018 at 7:56 PM "Richard (Rick) Karlquist"
> <richard@karlquist.com> wrote:
>
>
> On 6/10/2018 10:27 AM, Jim Thomson wrote:
>
> > ## Seems to me MFJ supplied a HP filter when using the MFJ-259B, to kill
> > anything < 1.8 mhz.
> >
> > Jim VE7RF
> >
>
> IIRC, what MFJ supplied was a tunable NOTCH filter, which might work OK
> in situations where there is only one station that is strong
> enough to upset the MFJ-259B. Of course you can't calibrate out
> the filter, so it could degrade measurement accuracy. Far from a panacea.
>
> My QTH is 6 miles from a 50 KW station on 1140 kHz. My 259B
> is useless on 160 meters and marginal on 80 meters. I vaguely
> remember the 259B getting messed up by a channel 3 TV station
> that is 8 miles from me running 100 KW. I don't have the MFJ notch filter.
>
> I recently got a Rig Expert AA-55 and it is unaffected by AM BCB QRM and
> works perfectly on my 160 meter vertical with no help from
> external filtering. It has many other advantages over the 259B.
>
> One thing you have to be careful about is to always use a DC
> block between the Rig Expert and the antenna. (You can calibrate out
> the DC block). Otherwise, static DC voltage could blow out the front
> end. I'm guessing that that is the likely reason why your Rig Expert
> failed.
>
> Rick N6RK
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